diff --git a/.gitignore b/.gitignore index c63d229..ad828bb 100644 --- a/.gitignore +++ b/.gitignore @@ -27,6 +27,10 @@ samples/*/bin/ *.fuzz coverage/ +# ASan/UBSan log output (the ASan test entries' log_path — +# tests/laige-render/CMakeLists.txt) +asan-reports/ + # Python artifacts (tools/ scripts) __pycache__/ *.pyc diff --git a/deps.lock b/deps.lock index 6d24bbe..afc8011 100644 --- a/deps.lock +++ b/deps.lock @@ -44,6 +44,17 @@ "sha256": "f4785f292cafd2b6e060705cc81e22ebf5d5083e27f1f155493e0f252ab9b395", "license": "MIT", "justification": "PRD §11 (math foundation for the rendering side: cameras, projection matrices, incl. isometric camera matrices; sim keeps its own fixed-point math per §10.3 — the include-graph lint owner rule keeps GLM out of sim): header-only, vendored (the full glm/ library tree of the pinned tag; doc/test/cmake excluded; M2-GL-03, ADR 0008)" + }, + { + "name": "stb", + "version": "2026-08-01", + "path": "deps/stb", + "owner": "src/laige-render", + "source_url": "https://github.com/nothings/stb", + "source_commit": "2c980bb59875b0d32144a71867fbdebb2f77cd20", + "sha256": "8f06584600718842d16098b13df213d0ec9ffecbf782a6fbadec3f4abf570685", + "license": "MIT-like (stb's no-warranty license; the text lives in deps/stb/LICENSE)", + "justification": "PRD §11 (font rasterization, FR-2.8 bitmap fonts P0 — the stb_truetype row): single-header C font rasterizer that M2-TEXT-01 uses to build the fixed bitmap glyph atlas (the M2-TEXT-03 SDF step reuses the same header); the implementation compiles in the laige-stb target with the plain compiler policy, pinned by this lock (M2-TEXT-01, ADR 0009)" } ] } diff --git a/deps/README.md b/deps/README.md index 0e0aaf8..b65cea2 100644 --- a/deps/README.md +++ b/deps/README.md @@ -4,7 +4,9 @@ Vendored third-party dependencies, each tracked in `deps.lock` (repo root; PRD §11, NFR-8.6, DEP-005). This directory landed with **M0-DEP-01**: the lock file, the configure-time hash check, and **GoogleTest** (dev-only); **M2-GL-01** adds **GLFW** (windowing) and the **GLAD-generated GL 3.3 -loader** (GL function access) for `src/laige-render`. +loader** (GL function access), **M2-GL-03** adds **GLM** (rendering-side +math), and **M2-TEXT-01** adds **stb_truetype** (font rasterization) — +all for `src/laige-render`. ## deps.lock @@ -45,9 +47,13 @@ recomputes the tree hash and rejects the configure. | GoogleTest | 1.18.0 | `googletest/` | `tests` (`tests/` only) | BSD-3-Clause | PRD §11 dev-only row (unit/integration tests; never shipped) | | GLFW | 3.5.1 | `glfw/` | `src/laige-render` | zlib | PRD §11 windowing row (M2-GL-01: windowed + hidden-window context creation on all P0 OSes) | | GLAD (generated) | 2.0.8 | `glad/` | `src/laige-render` | WTFPL OR CC0-1.0 AND Apache-2.0 | PRD §11 GL-loader row (M2-GL-01: GL 3.3 core function access; the vendored artifact is the reproducible `gladv2 --api gl:core=3.3` output, not a source checkout) | +| GLM | 1.0.3 | `glm/` | `src/laige-render` | MIT | PRD §11 math-foundation row (M2-GL-03: rendering-side value types for cameras/projection matrices; the full `glm/` tree of the pinned tag) | +| stb (stb_truetype) | 2026-08-01 | `stb/` | `src/laige-render` | MIT-like (stb license) | PRD §11 font-rasterization row (M2-TEXT-01: bitmap glyph atlas rasterization for FR-2.8 P0; the single header `stb_truetype.h` + `LICENSE`, pinned commit — stb publishes no release tags) | -See [ADR 0004](../docs/decisions/0004-google-test-vendoring.md) (GoogleTest) -and [ADR 0007](../docs/decisions/0007-glfw-glad-vendoring.md) (GLFW + GLAD) +See [ADR 0004](../docs/decisions/0004-google-test-vendoring.md) (GoogleTest), +[ADR 0007](../docs/decisions/0007-glfw-glad-vendoring.md) (GLFW + GLAD), +[ADR 0008](../docs/decisions/0008-glm-vendoring.md) (GLM), and +[ADR 0009](../docs/decisions/0009-stb-truetype-vendoring.md) (stb_truetype) for the full DEP-003 justifications and the upgrade/removal strategy. ## Adding or updating a dependency diff --git a/deps/stb/LICENSE b/deps/stb/LICENSE new file mode 100644 index 0000000..a77ae91 --- /dev/null +++ b/deps/stb/LICENSE @@ -0,0 +1,37 @@ +This software is available under 2 licenses -- choose whichever you prefer. +------------------------------------------------------------------------------ +ALTERNATIVE A - MIT License +Copyright (c) 2017 Sean Barrett +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files (the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions: +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +------------------------------------------------------------------------------ +ALTERNATIVE B - Public Domain (www.unlicense.org) +This is free and unencumbered software released into the public domain. +Anyone is free to copy, modify, publish, use, compile, sell, or distribute this +software, either in source code form or as a compiled binary, for any purpose, +commercial or non-commercial, and by any means. +In jurisdictions that recognize copyright laws, the author or authors of this +software dedicate any and all copyright interest in the software to the public +domain. We make this dedication for the benefit of the public at large and to +the detriment of our heirs and successors. We intend this dedication to be an +overt act of relinquishment in perpetuity of all present and future rights to +this software under copyright law. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. diff --git a/deps/stb/stb_truetype.h b/deps/stb/stb_truetype.h new file mode 100644 index 0000000..90a5c2e --- /dev/null +++ b/deps/stb/stb_truetype.h @@ -0,0 +1,5079 @@ +// stb_truetype.h - v1.26 - public domain +// authored from 2009-2021 by Sean Barrett / RAD Game Tools +// +// ======================================================================= +// +// NO SECURITY GUARANTEE -- DO NOT USE THIS ON UNTRUSTED FONT FILES +// +// This library does no range checking of the offsets found in the file, +// meaning an attacker can use it to read arbitrary memory. +// +// ======================================================================= +// +// This library processes TrueType files: +// parse files +// extract glyph metrics +// extract glyph shapes +// render glyphs to one-channel bitmaps with antialiasing (box filter) +// render glyphs to one-channel SDF bitmaps (signed-distance field/function) +// +// Todo: +// non-MS cmaps +// crashproof on bad data +// hinting? (no longer patented) +// cleartype-style AA? +// optimize: use simple memory allocator for intermediates +// optimize: build edge-list directly from curves +// optimize: rasterize directly from curves? +// +// ADDITIONAL CONTRIBUTORS +// +// Mikko Mononen: compound shape support, more cmap formats +// Tor Andersson: kerning, subpixel rendering +// Dougall Johnson: OpenType / Type 2 font handling +// Daniel Ribeiro Maciel: basic GPOS-based kerning +// +// Misc other: +// Ryan Gordon +// Simon Glass +// github:IntellectualKitty +// Imanol Celaya +// Daniel Ribeiro Maciel +// +// Bug/warning reports/fixes: +// "Zer" on mollyrocket Fabian "ryg" Giesen github:NiLuJe +// Cass Everitt Martins Mozeiko github:aloucks +// stoiko (Haemimont Games) Cap Petschulat github:oyvindjam +// Brian Hook Omar Cornut github:vassvik +// Walter van Niftrik Ryan Griege +// David Gow Peter LaValle +// David Given Sergey Popov +// Ivan-Assen Ivanov Giumo X. Clanjor +// Anthony Pesch Higor Euripedes +// Johan Duparc Thomas Fields +// Hou Qiming Derek Vinyard +// Rob Loach Cort Stratton +// Kenney Phillis Jr. Brian Costabile +// Ken Voskuil (kaesve) Yakov Galka +// +// VERSION HISTORY +// +// 1.26 (2021-08-28) fix broken rasterizer +// 1.25 (2021-07-11) many fixes +// 1.24 (2020-02-05) fix warning +// 1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS) +// 1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined +// 1.21 (2019-02-25) fix warning +// 1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics() +// 1.19 (2018-02-11) GPOS kerning, STBTT_fmod +// 1.18 (2018-01-29) add missing function +// 1.17 (2017-07-23) make more arguments const; doc fix +// 1.16 (2017-07-12) SDF support +// 1.15 (2017-03-03) make more arguments const +// 1.14 (2017-01-16) num-fonts-in-TTC function +// 1.13 (2017-01-02) support OpenType fonts, certain Apple fonts +// 1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual +// 1.11 (2016-04-02) fix unused-variable warning +// 1.10 (2016-04-02) user-defined fabs(); rare memory leak; remove duplicate typedef +// 1.09 (2016-01-16) warning fix; avoid crash on outofmem; use allocation userdata properly +// 1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges +// 1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints; +// variant PackFontRanges to pack and render in separate phases; +// fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?); +// fixed an assert() bug in the new rasterizer +// replace assert() with STBTT_assert() in new rasterizer +// +// Full history can be found at the end of this file. +// +// LICENSE +// +// See end of file for license information. +// +// USAGE +// +// Include this file in whatever places need to refer to it. In ONE C/C++ +// file, write: +// #define STB_TRUETYPE_IMPLEMENTATION +// before the #include of this file. This expands out the actual +// implementation into that C/C++ file. +// +// To make the implementation private to the file that generates the implementation, +// #define STBTT_STATIC +// +// Simple 3D API (don't ship this, but it's fine for tools and quick start) +// stbtt_BakeFontBitmap() -- bake a font to a bitmap for use as texture +// stbtt_GetBakedQuad() -- compute quad to draw for a given char +// +// Improved 3D API (more shippable): +// #include "stb_rect_pack.h" -- optional, but you really want it +// stbtt_PackBegin() +// stbtt_PackSetOversampling() -- for improved quality on small fonts +// stbtt_PackFontRanges() -- pack and renders +// stbtt_PackEnd() +// stbtt_GetPackedQuad() +// +// "Load" a font file from a memory buffer (you have to keep the buffer loaded) +// stbtt_InitFont() +// stbtt_GetFontOffsetForIndex() -- indexing for TTC font collections +// stbtt_GetNumberOfFonts() -- number of fonts for TTC font collections +// +// Render a unicode codepoint to a bitmap +// stbtt_GetCodepointBitmap() -- allocates and returns a bitmap +// stbtt_MakeCodepointBitmap() -- renders into bitmap you provide +// stbtt_GetCodepointBitmapBox() -- how big the bitmap must be +// +// Character advance/positioning +// stbtt_GetCodepointHMetrics() +// stbtt_GetFontVMetrics() +// stbtt_GetFontVMetricsOS2() +// stbtt_GetCodepointKernAdvance() +// +// Starting with version 1.06, the rasterizer was replaced with a new, +// faster and generally-more-precise rasterizer. The new rasterizer more +// accurately measures pixel coverage for anti-aliasing, except in the case +// where multiple shapes overlap, in which case it overestimates the AA pixel +// coverage. Thus, anti-aliasing of intersecting shapes may look wrong. If +// this turns out to be a problem, you can re-enable the old rasterizer with +// #define STBTT_RASTERIZER_VERSION 1 +// which will incur about a 15% speed hit. +// +// ADDITIONAL DOCUMENTATION +// +// Immediately after this block comment are a series of sample programs. +// +// After the sample programs is the "header file" section. This section +// includes documentation for each API function. +// +// Some important concepts to understand to use this library: +// +// Codepoint +// Characters are defined by unicode codepoints, e.g. 65 is +// uppercase A, 231 is lowercase c with a cedilla, 0x7e30 is +// the hiragana for "ma". +// +// Glyph +// A visual character shape (every codepoint is rendered as +// some glyph) +// +// Glyph index +// A font-specific integer ID representing a glyph +// +// Baseline +// Glyph shapes are defined relative to a baseline, which is the +// bottom of uppercase characters. Characters extend both above +// and below the baseline. +// +// Current Point +// As you draw text to the screen, you keep track of a "current point" +// which is the origin of each character. The current point's vertical +// position is the baseline. Even "baked fonts" use this model. +// +// Vertical Font Metrics +// The vertical qualities of the font, used to vertically position +// and space the characters. See docs for stbtt_GetFontVMetrics. +// +// Font Size in Pixels or Points +// The preferred interface for specifying font sizes in stb_truetype +// is to specify how tall the font's vertical extent should be in pixels. +// If that sounds good enough, skip the next paragraph. +// +// Most font APIs instead use "points", which are a common typographic +// measurement for describing font size, defined as 72 points per inch. +// stb_truetype provides a point API for compatibility. However, true +// "per inch" conventions don't make much sense on computer displays +// since different monitors have different number of pixels per +// inch. For example, Windows traditionally uses a convention that +// there are 96 pixels per inch, thus making 'inch' measurements have +// nothing to do with inches, and thus effectively defining a point to +// be 1.333 pixels. Additionally, the TrueType font data provides +// an explicit scale factor to scale a given font's glyphs to points, +// but the author has observed that this scale factor is often wrong +// for non-commercial fonts, thus making fonts scaled in points +// according to the TrueType spec incoherently sized in practice. +// +// DETAILED USAGE: +// +// Scale: +// Select how high you want the font to be, in points or pixels. +// Call ScaleForPixelHeight or ScaleForMappingEmToPixels to compute +// a scale factor SF that will be used by all other functions. +// +// Baseline: +// You need to select a y-coordinate that is the baseline of where +// your text will appear. Call GetFontBoundingBox to get the baseline-relative +// bounding box for all characters. SF*-y0 will be the distance in pixels +// that the worst-case character could extend above the baseline, so if +// you want the top edge of characters to appear at the top of the +// screen where y=0, then you would set the baseline to SF*-y0. +// +// Current point: +// Set the current point where the first character will appear. The +// first character could extend left of the current point; this is font +// dependent. You can either choose a current point that is the leftmost +// point and hope, or add some padding, or check the bounding box or +// left-side-bearing of the first character to be displayed and set +// the current point based on that. +// +// Displaying a character: +// Compute the bounding box of the character. It will contain signed values +// relative to . I.e. if it returns x0,y0,x1,y1, +// then the character should be displayed in the rectangle from +// to = 32 && *text < 128) { + stbtt_aligned_quad q; + stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9 + glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y0); + glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y0); + glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y1); + glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y1); + } + ++text; + } + glEnd(); +} +#endif +// +// +////////////////////////////////////////////////////////////////////////////// +// +// Complete program (this compiles): get a single bitmap, print as ASCII art +// +#if 0 +#include +#define STB_TRUETYPE_IMPLEMENTATION // force following include to generate implementation +#include "stb_truetype.h" + +char ttf_buffer[1<<25]; + +int main(int argc, char **argv) +{ + stbtt_fontinfo font; + unsigned char *bitmap; + int w,h,i,j,c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20); + + fread(ttf_buffer, 1, 1<<25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb")); + + stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer,0)); + bitmap = stbtt_GetCodepointBitmap(&font, 0,stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0,0); + + for (j=0; j < h; ++j) { + for (i=0; i < w; ++i) + putchar(" .:ioVM@"[bitmap[j*w+i]>>5]); + putchar('\n'); + } + return 0; +} +#endif +// +// Output: +// +// .ii. +// @@@@@@. +// V@Mio@@o +// :i. V@V +// :oM@@M +// :@@@MM@M +// @@o o@M +// :@@. M@M +// @@@o@@@@ +// :M@@V:@@. +// +////////////////////////////////////////////////////////////////////////////// +// +// Complete program: print "Hello World!" banner, with bugs +// +#if 0 +char buffer[24<<20]; +unsigned char screen[20][79]; + +int main(int arg, char **argv) +{ + stbtt_fontinfo font; + int i,j,ascent,baseline,ch=0; + float scale, xpos=2; // leave a little padding in case the character extends left + char *text = "Heljo World!"; // intentionally misspelled to show 'lj' brokenness + + fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb")); + stbtt_InitFont(&font, buffer, 0); + + scale = stbtt_ScaleForPixelHeight(&font, 15); + stbtt_GetFontVMetrics(&font, &ascent,0,0); + baseline = (int) (ascent*scale); + + while (text[ch]) { + int advance,lsb,x0,y0,x1,y1; + float x_shift = xpos - (float) floor(xpos); + stbtt_GetCodepointHMetrics(&font, text[ch], &advance, &lsb); + stbtt_GetCodepointBitmapBoxSubpixel(&font, text[ch], scale,scale,x_shift,0, &x0,&y0,&x1,&y1); + stbtt_MakeCodepointBitmapSubpixel(&font, &screen[baseline + y0][(int) xpos + x0], x1-x0,y1-y0, 79, scale,scale,x_shift,0, text[ch]); + // note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong + // because this API is really for baking character bitmaps into textures. if you want to render + // a sequence of characters, you really need to render each bitmap to a temp buffer, then + // "alpha blend" that into the working buffer + xpos += (advance * scale); + if (text[ch+1]) + xpos += scale*stbtt_GetCodepointKernAdvance(&font, text[ch],text[ch+1]); + ++ch; + } + + for (j=0; j < 20; ++j) { + for (i=0; i < 78; ++i) + putchar(" .:ioVM@"[screen[j][i]>>5]); + putchar('\n'); + } + + return 0; +} +#endif + + +////////////////////////////////////////////////////////////////////////////// +////////////////////////////////////////////////////////////////////////////// +//// +//// INTEGRATION WITH YOUR CODEBASE +//// +//// The following sections allow you to supply alternate definitions +//// of C library functions used by stb_truetype, e.g. if you don't +//// link with the C runtime library. + +#ifdef STB_TRUETYPE_IMPLEMENTATION + // #define your own (u)stbtt_int8/16/32 before including to override this + #ifndef stbtt_uint8 + typedef unsigned char stbtt_uint8; + typedef signed char stbtt_int8; + typedef unsigned short stbtt_uint16; + typedef signed short stbtt_int16; + typedef unsigned int stbtt_uint32; + typedef signed int stbtt_int32; + #endif + + typedef char stbtt__check_size32[sizeof(stbtt_int32)==4 ? 1 : -1]; + typedef char stbtt__check_size16[sizeof(stbtt_int16)==2 ? 1 : -1]; + + // e.g. #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h + #ifndef STBTT_ifloor + #include + #define STBTT_ifloor(x) ((int) floor(x)) + #define STBTT_iceil(x) ((int) ceil(x)) + #endif + + #ifndef STBTT_sqrt + #include + #define STBTT_sqrt(x) sqrt(x) + #define STBTT_pow(x,y) pow(x,y) + #endif + + #ifndef STBTT_fmod + #include + #define STBTT_fmod(x,y) fmod(x,y) + #endif + + #ifndef STBTT_cos + #include + #define STBTT_cos(x) cos(x) + #define STBTT_acos(x) acos(x) + #endif + + #ifndef STBTT_fabs + #include + #define STBTT_fabs(x) fabs(x) + #endif + + // #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h + #ifndef STBTT_malloc + #include + #define STBTT_malloc(x,u) ((void)(u),malloc(x)) + #define STBTT_free(x,u) ((void)(u),free(x)) + #endif + + #ifndef STBTT_assert + #include + #define STBTT_assert(x) assert(x) + #endif + + #ifndef STBTT_strlen + #include + #define STBTT_strlen(x) strlen(x) + #endif + + #ifndef STBTT_memcpy + #include + #define STBTT_memcpy memcpy + #define STBTT_memset memset + #endif +#endif + +/////////////////////////////////////////////////////////////////////////////// +/////////////////////////////////////////////////////////////////////////////// +//// +//// INTERFACE +//// +//// + +#ifndef __STB_INCLUDE_STB_TRUETYPE_H__ +#define __STB_INCLUDE_STB_TRUETYPE_H__ + +#ifdef STBTT_STATIC +#define STBTT_DEF static +#else +#define STBTT_DEF extern +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +// private structure +typedef struct +{ + unsigned char *data; + int cursor; + int size; +} stbtt__buf; + +////////////////////////////////////////////////////////////////////////////// +// +// TEXTURE BAKING API +// +// If you use this API, you only have to call two functions ever. +// + +typedef struct +{ + unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap + float xoff,yoff,xadvance; +} stbtt_bakedchar; + +STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset, // font location (use offset=0 for plain .ttf) + float pixel_height, // height of font in pixels + unsigned char *pixels, int pw, int ph, // bitmap to be filled in + int first_char, int num_chars, // characters to bake + stbtt_bakedchar *chardata); // you allocate this, it's num_chars long +// if return is positive, the first unused row of the bitmap +// if return is negative, returns the negative of the number of characters that fit +// if return is 0, no characters fit and no rows were used +// This uses a very crappy packing. + +typedef struct +{ + float x0,y0,s0,t0; // top-left + float x1,y1,s1,t1; // bottom-right +} stbtt_aligned_quad; + +STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph, // same data as above + int char_index, // character to display + float *xpos, float *ypos, // pointers to current position in screen pixel space + stbtt_aligned_quad *q, // output: quad to draw + int opengl_fillrule); // true if opengl fill rule; false if DX9 or earlier +// Call GetBakedQuad with char_index = 'character - first_char', and it +// creates the quad you need to draw and advances the current position. +// +// The coordinate system used assumes y increases downwards. +// +// Characters will extend both above and below the current position; +// see discussion of "BASELINE" above. +// +// It's inefficient; you might want to c&p it and optimize it. + +STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap); +// Query the font vertical metrics without having to create a font first. + + +////////////////////////////////////////////////////////////////////////////// +// +// NEW TEXTURE BAKING API +// +// This provides options for packing multiple fonts into one atlas, not +// perfectly but better than nothing. + +typedef struct +{ + unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap + float xoff,yoff,xadvance; + float xoff2,yoff2; +} stbtt_packedchar; + +typedef struct stbtt_pack_context stbtt_pack_context; +typedef struct stbtt_fontinfo stbtt_fontinfo; +#ifndef STB_RECT_PACK_VERSION +typedef struct stbrp_rect stbrp_rect; +#endif + +STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int width, int height, int stride_in_bytes, int padding, void *alloc_context); +// Initializes a packing context stored in the passed-in stbtt_pack_context. +// Future calls using this context will pack characters into the bitmap passed +// in here: a 1-channel bitmap that is width * height. stride_in_bytes is +// the distance from one row to the next (or 0 to mean they are packed tightly +// together). "padding" is the amount of padding to leave between each +// character (normally you want '1' for bitmaps you'll use as textures with +// bilinear filtering). +// +// Returns 0 on failure, 1 on success. + +STBTT_DEF void stbtt_PackEnd (stbtt_pack_context *spc); +// Cleans up the packing context and frees all memory. + +#define STBTT_POINT_SIZE(x) (-(x)) + +STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size, + int first_unicode_char_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range); +// Creates character bitmaps from the font_index'th font found in fontdata (use +// font_index=0 if you don't know what that is). It creates num_chars_in_range +// bitmaps for characters with unicode values starting at first_unicode_char_in_range +// and increasing. Data for how to render them is stored in chardata_for_range; +// pass these to stbtt_GetPackedQuad to get back renderable quads. +// +// font_size is the full height of the character from ascender to descender, +// as computed by stbtt_ScaleForPixelHeight. To use a point size as computed +// by stbtt_ScaleForMappingEmToPixels, wrap the point size in STBTT_POINT_SIZE() +// and pass that result as 'font_size': +// ..., 20 , ... // font max minus min y is 20 pixels tall +// ..., STBTT_POINT_SIZE(20), ... // 'M' is 20 pixels tall + +typedef struct +{ + float font_size; + int first_unicode_codepoint_in_range; // if non-zero, then the chars are continuous, and this is the first codepoint + int *array_of_unicode_codepoints; // if non-zero, then this is an array of unicode codepoints + int num_chars; + stbtt_packedchar *chardata_for_range; // output + unsigned char h_oversample, v_oversample; // don't set these, they're used internally +} stbtt_pack_range; + +STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges); +// Creates character bitmaps from multiple ranges of characters stored in +// ranges. This will usually create a better-packed bitmap than multiple +// calls to stbtt_PackFontRange. Note that you can call this multiple +// times within a single PackBegin/PackEnd. + +STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample); +// Oversampling a font increases the quality by allowing higher-quality subpixel +// positioning, and is especially valuable at smaller text sizes. +// +// This function sets the amount of oversampling for all following calls to +// stbtt_PackFontRange(s) or stbtt_PackFontRangesGatherRects for a given +// pack context. The default (no oversampling) is achieved by h_oversample=1 +// and v_oversample=1. The total number of pixels required is +// h_oversample*v_oversample larger than the default; for example, 2x2 +// oversampling requires 4x the storage of 1x1. For best results, render +// oversampled textures with bilinear filtering. Look at the readme in +// stb/tests/oversample for information about oversampled fonts +// +// To use with PackFontRangesGather etc., you must set it before calls +// call to PackFontRangesGatherRects. + +STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip); +// If skip != 0, this tells stb_truetype to skip any codepoints for which +// there is no corresponding glyph. If skip=0, which is the default, then +// codepoints without a glyph recived the font's "missing character" glyph, +// typically an empty box by convention. + +STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph, // same data as above + int char_index, // character to display + float *xpos, float *ypos, // pointers to current position in screen pixel space + stbtt_aligned_quad *q, // output: quad to draw + int align_to_integer); + +STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects); +STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects); +STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects); +// Calling these functions in sequence is roughly equivalent to calling +// stbtt_PackFontRanges(). If you more control over the packing of multiple +// fonts, or if you want to pack custom data into a font texture, take a look +// at the source to of stbtt_PackFontRanges() and create a custom version +// using these functions, e.g. call GatherRects multiple times, +// building up a single array of rects, then call PackRects once, +// then call RenderIntoRects repeatedly. This may result in a +// better packing than calling PackFontRanges multiple times +// (or it may not). + +// this is an opaque structure that you shouldn't mess with which holds +// all the context needed from PackBegin to PackEnd. +struct stbtt_pack_context { + void *user_allocator_context; + void *pack_info; + int width; + int height; + int stride_in_bytes; + int padding; + int skip_missing; + unsigned int h_oversample, v_oversample; + unsigned char *pixels; + void *nodes; +}; + +////////////////////////////////////////////////////////////////////////////// +// +// FONT LOADING +// +// + +STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data); +// This function will determine the number of fonts in a font file. TrueType +// collection (.ttc) files may contain multiple fonts, while TrueType font +// (.ttf) files only contain one font. The number of fonts can be used for +// indexing with the previous function where the index is between zero and one +// less than the total fonts. If an error occurs, -1 is returned. + +STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index); +// Each .ttf/.ttc file may have more than one font. Each font has a sequential +// index number starting from 0. Call this function to get the font offset for +// a given index; it returns -1 if the index is out of range. A regular .ttf +// file will only define one font and it always be at offset 0, so it will +// return '0' for index 0, and -1 for all other indices. + +// The following structure is defined publicly so you can declare one on +// the stack or as a global or etc, but you should treat it as opaque. +struct stbtt_fontinfo +{ + void * userdata; + unsigned char * data; // pointer to .ttf file + int fontstart; // offset of start of font + + int numGlyphs; // number of glyphs, needed for range checking + + int loca,head,glyf,hhea,hmtx,kern,gpos,svg; // table locations as offset from start of .ttf + int index_map; // a cmap mapping for our chosen character encoding + int indexToLocFormat; // format needed to map from glyph index to glyph + + stbtt__buf cff; // cff font data + stbtt__buf charstrings; // the charstring index + stbtt__buf gsubrs; // global charstring subroutines index + stbtt__buf subrs; // private charstring subroutines index + stbtt__buf fontdicts; // array of font dicts + stbtt__buf fdselect; // map from glyph to fontdict +}; + +STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset); +// Given an offset into the file that defines a font, this function builds +// the necessary cached info for the rest of the system. You must allocate +// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't +// need to do anything special to free it, because the contents are pure +// value data with no additional data structures. Returns 0 on failure. + + +////////////////////////////////////////////////////////////////////////////// +// +// CHARACTER TO GLYPH-INDEX CONVERSIOn + +STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint); +// If you're going to perform multiple operations on the same character +// and you want a speed-up, call this function with the character you're +// going to process, then use glyph-based functions instead of the +// codepoint-based functions. +// Returns 0 if the character codepoint is not defined in the font. + + +////////////////////////////////////////////////////////////////////////////// +// +// CHARACTER PROPERTIES +// + +STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels); +// computes a scale factor to produce a font whose "height" is 'pixels' tall. +// Height is measured as the distance from the highest ascender to the lowest +// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics +// and computing: +// scale = pixels / (ascent - descent) +// so if you prefer to measure height by the ascent only, use a similar calculation. + +STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels); +// computes a scale factor to produce a font whose EM size is mapped to +// 'pixels' tall. This is probably what traditional APIs compute, but +// I'm not positive. + +STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap); +// ascent is the coordinate above the baseline the font extends; descent +// is the coordinate below the baseline the font extends (i.e. it is typically negative) +// lineGap is the spacing between one row's descent and the next row's ascent... +// so you should advance the vertical position by "*ascent - *descent + *lineGap" +// these are expressed in unscaled coordinates, so you must multiply by +// the scale factor for a given size + +STBTT_DEF int stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap); +// analogous to GetFontVMetrics, but returns the "typographic" values from the OS/2 +// table (specific to MS/Windows TTF files). +// +// Returns 1 on success (table present), 0 on failure. + +STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1); +// the bounding box around all possible characters + +STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing); +// leftSideBearing is the offset from the current horizontal position to the left edge of the character +// advanceWidth is the offset from the current horizontal position to the next horizontal position +// these are expressed in unscaled coordinates + +STBTT_DEF int stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2); +// an additional amount to add to the 'advance' value between ch1 and ch2 + +STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1); +// Gets the bounding box of the visible part of the glyph, in unscaled coordinates + +STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing); +STBTT_DEF int stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2); +STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1); +// as above, but takes one or more glyph indices for greater efficiency + +typedef struct stbtt_kerningentry +{ + int glyph1; // use stbtt_FindGlyphIndex + int glyph2; + int advance; +} stbtt_kerningentry; + +STBTT_DEF int stbtt_GetKerningTableLength(const stbtt_fontinfo *info); +STBTT_DEF int stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length); +// Retrieves a complete list of all of the kerning pairs provided by the font +// stbtt_GetKerningTable never writes more than table_length entries and returns how many entries it did write. +// The table will be sorted by (a.glyph1 == b.glyph1)?(a.glyph2 < b.glyph2):(a.glyph1 < b.glyph1) + +////////////////////////////////////////////////////////////////////////////// +// +// GLYPH SHAPES (you probably don't need these, but they have to go before +// the bitmaps for C declaration-order reasons) +// + +#ifndef STBTT_vmove // you can predefine these to use different values (but why?) + enum { + STBTT_vmove=1, + STBTT_vline, + STBTT_vcurve, + STBTT_vcubic + }; +#endif + +#ifndef stbtt_vertex // you can predefine this to use different values + // (we share this with other code at RAD) + #define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file + typedef struct + { + stbtt_vertex_type x,y,cx,cy,cx1,cy1; + unsigned char type,padding; + } stbtt_vertex; +#endif + +STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index); +// returns non-zero if nothing is drawn for this glyph + +STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices); +STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices); +// returns # of vertices and fills *vertices with the pointer to them +// these are expressed in "unscaled" coordinates +// +// The shape is a series of contours. Each one starts with +// a STBTT_moveto, then consists of a series of mixed +// STBTT_lineto and STBTT_curveto segments. A lineto +// draws a line from previous endpoint to its x,y; a curveto +// draws a quadratic bezier from previous endpoint to +// its x,y, using cx,cy as the bezier control point. + +STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices); +// frees the data allocated above + +STBTT_DEF unsigned char *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl); +STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg); +STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg); +// fills svg with the character's SVG data. +// returns data size or 0 if SVG not found. + +////////////////////////////////////////////////////////////////////////////// +// +// BITMAP RENDERING +// + +STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata); +// frees the bitmap allocated below + +STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff); +// allocates a large-enough single-channel 8bpp bitmap and renders the +// specified character/glyph at the specified scale into it, with +// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque). +// *width & *height are filled out with the width & height of the bitmap, +// which is stored left-to-right, top-to-bottom. +// +// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap + +STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff); +// the same as stbtt_GetCodepoitnBitmap, but you can specify a subpixel +// shift for the character + +STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint); +// the same as stbtt_GetCodepointBitmap, but you pass in storage for the bitmap +// in the form of 'output', with row spacing of 'out_stride' bytes. the bitmap +// is clipped to out_w/out_h bytes. Call stbtt_GetCodepointBitmapBox to get the +// width and height and positioning info for it first. + +STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint); +// same as stbtt_MakeCodepointBitmap, but you can specify a subpixel +// shift for the character + +STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint); +// same as stbtt_MakeCodepointBitmapSubpixel, but prefiltering +// is performed (see stbtt_PackSetOversampling) + +STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1); +// get the bbox of the bitmap centered around the glyph origin; so the +// bitmap width is ix1-ix0, height is iy1-iy0, and location to place +// the bitmap top left is (leftSideBearing*scale,iy0). +// (Note that the bitmap uses y-increases-down, but the shape uses +// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.) + +STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1); +// same as stbtt_GetCodepointBitmapBox, but you can specify a subpixel +// shift for the character + +// the following functions are equivalent to the above functions, but operate +// on glyph indices instead of Unicode codepoints (for efficiency) +STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff); +STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff); +STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph); +STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph); +STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int glyph); +STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1); +STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1); + + +// @TODO: don't expose this structure +typedef struct +{ + int w,h,stride; + unsigned char *pixels; +} stbtt__bitmap; + +// rasterize a shape with quadratic beziers into a bitmap +STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, // 1-channel bitmap to draw into + float flatness_in_pixels, // allowable error of curve in pixels + stbtt_vertex *vertices, // array of vertices defining shape + int num_verts, // number of vertices in above array + float scale_x, float scale_y, // scale applied to input vertices + float shift_x, float shift_y, // translation applied to input vertices + int x_off, int y_off, // another translation applied to input + int invert, // if non-zero, vertically flip shape + void *userdata); // context for to STBTT_MALLOC + +////////////////////////////////////////////////////////////////////////////// +// +// Signed Distance Function (or Field) rendering + +STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata); +// frees the SDF bitmap allocated below + +STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff); +STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff); +// These functions compute a discretized SDF field for a single character, suitable for storing +// in a single-channel texture, sampling with bilinear filtering, and testing against +// larger than some threshold to produce scalable fonts. +// info -- the font +// scale -- controls the size of the resulting SDF bitmap, same as it would be creating a regular bitmap +// glyph/codepoint -- the character to generate the SDF for +// padding -- extra "pixels" around the character which are filled with the distance to the character (not 0), +// which allows effects like bit outlines +// onedge_value -- value 0-255 to test the SDF against to reconstruct the character (i.e. the isocontour of the character) +// pixel_dist_scale -- what value the SDF should increase by when moving one SDF "pixel" away from the edge (on the 0..255 scale) +// if positive, > onedge_value is inside; if negative, < onedge_value is inside +// width,height -- output height & width of the SDF bitmap (including padding) +// xoff,yoff -- output origin of the character +// return value -- a 2D array of bytes 0..255, width*height in size +// +// pixel_dist_scale & onedge_value are a scale & bias that allows you to make +// optimal use of the limited 0..255 for your application, trading off precision +// and special effects. SDF values outside the range 0..255 are clamped to 0..255. +// +// Example: +// scale = stbtt_ScaleForPixelHeight(22) +// padding = 5 +// onedge_value = 180 +// pixel_dist_scale = 180/5.0 = 36.0 +// +// This will create an SDF bitmap in which the character is about 22 pixels +// high but the whole bitmap is about 22+5+5=32 pixels high. To produce a filled +// shape, sample the SDF at each pixel and fill the pixel if the SDF value +// is greater than or equal to 180/255. (You'll actually want to antialias, +// which is beyond the scope of this example.) Additionally, you can compute +// offset outlines (e.g. to stroke the character border inside & outside, +// or only outside). For example, to fill outside the character up to 3 SDF +// pixels, you would compare against (180-36.0*3)/255 = 72/255. The above +// choice of variables maps a range from 5 pixels outside the shape to +// 2 pixels inside the shape to 0..255; this is intended primarily for apply +// outside effects only (the interior range is needed to allow proper +// antialiasing of the font at *smaller* sizes) +// +// The function computes the SDF analytically at each SDF pixel, not by e.g. +// building a higher-res bitmap and approximating it. In theory the quality +// should be as high as possible for an SDF of this size & representation, but +// unclear if this is true in practice (perhaps building a higher-res bitmap +// and computing from that can allow drop-out prevention). +// +// The algorithm has not been optimized at all, so expect it to be slow +// if computing lots of characters or very large sizes. + + + +////////////////////////////////////////////////////////////////////////////// +// +// Finding the right font... +// +// You should really just solve this offline, keep your own tables +// of what font is what, and don't try to get it out of the .ttf file. +// That's because getting it out of the .ttf file is really hard, because +// the names in the file can appear in many possible encodings, in many +// possible languages, and e.g. if you need a case-insensitive comparison, +// the details of that depend on the encoding & language in a complex way +// (actually underspecified in truetype, but also gigantic). +// +// But you can use the provided functions in two possible ways: +// stbtt_FindMatchingFont() will use *case-sensitive* comparisons on +// unicode-encoded names to try to find the font you want; +// you can run this before calling stbtt_InitFont() +// +// stbtt_GetFontNameString() lets you get any of the various strings +// from the file yourself and do your own comparisons on them. +// You have to have called stbtt_InitFont() first. + + +STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags); +// returns the offset (not index) of the font that matches, or -1 if none +// if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold". +// if you use any other flag, use a font name like "Arial"; this checks +// the 'macStyle' header field; i don't know if fonts set this consistently +#define STBTT_MACSTYLE_DONTCARE 0 +#define STBTT_MACSTYLE_BOLD 1 +#define STBTT_MACSTYLE_ITALIC 2 +#define STBTT_MACSTYLE_UNDERSCORE 4 +#define STBTT_MACSTYLE_NONE 8 // <= not same as 0, this makes us check the bitfield is 0 + +STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2); +// returns 1/0 whether the first string interpreted as utf8 is identical to +// the second string interpreted as big-endian utf16... useful for strings from next func + +STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID); +// returns the string (which may be big-endian double byte, e.g. for unicode) +// and puts the length in bytes in *length. +// +// some of the values for the IDs are below; for more see the truetype spec: +// http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html +// http://www.microsoft.com/typography/otspec/name.htm + +enum { // platformID + STBTT_PLATFORM_ID_UNICODE =0, + STBTT_PLATFORM_ID_MAC =1, + STBTT_PLATFORM_ID_ISO =2, + STBTT_PLATFORM_ID_MICROSOFT =3 +}; + +enum { // encodingID for STBTT_PLATFORM_ID_UNICODE + STBTT_UNICODE_EID_UNICODE_1_0 =0, + STBTT_UNICODE_EID_UNICODE_1_1 =1, + STBTT_UNICODE_EID_ISO_10646 =2, + STBTT_UNICODE_EID_UNICODE_2_0_BMP=3, + STBTT_UNICODE_EID_UNICODE_2_0_FULL=4 +}; + +enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT + STBTT_MS_EID_SYMBOL =0, + STBTT_MS_EID_UNICODE_BMP =1, + STBTT_MS_EID_SHIFTJIS =2, + STBTT_MS_EID_UNICODE_FULL =10 +}; + +enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes + STBTT_MAC_EID_ROMAN =0, STBTT_MAC_EID_ARABIC =4, + STBTT_MAC_EID_JAPANESE =1, STBTT_MAC_EID_HEBREW =5, + STBTT_MAC_EID_CHINESE_TRAD =2, STBTT_MAC_EID_GREEK =6, + STBTT_MAC_EID_KOREAN =3, STBTT_MAC_EID_RUSSIAN =7 +}; + +enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID... + // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs + STBTT_MS_LANG_ENGLISH =0x0409, STBTT_MS_LANG_ITALIAN =0x0410, + STBTT_MS_LANG_CHINESE =0x0804, STBTT_MS_LANG_JAPANESE =0x0411, + STBTT_MS_LANG_DUTCH =0x0413, STBTT_MS_LANG_KOREAN =0x0412, + STBTT_MS_LANG_FRENCH =0x040c, STBTT_MS_LANG_RUSSIAN =0x0419, + STBTT_MS_LANG_GERMAN =0x0407, STBTT_MS_LANG_SPANISH =0x0409, + STBTT_MS_LANG_HEBREW =0x040d, STBTT_MS_LANG_SWEDISH =0x041D +}; + +enum { // languageID for STBTT_PLATFORM_ID_MAC + STBTT_MAC_LANG_ENGLISH =0 , STBTT_MAC_LANG_JAPANESE =11, + STBTT_MAC_LANG_ARABIC =12, STBTT_MAC_LANG_KOREAN =23, + STBTT_MAC_LANG_DUTCH =4 , STBTT_MAC_LANG_RUSSIAN =32, + STBTT_MAC_LANG_FRENCH =1 , STBTT_MAC_LANG_SPANISH =6 , + STBTT_MAC_LANG_GERMAN =2 , STBTT_MAC_LANG_SWEDISH =5 , + STBTT_MAC_LANG_HEBREW =10, STBTT_MAC_LANG_CHINESE_SIMPLIFIED =33, + STBTT_MAC_LANG_ITALIAN =3 , STBTT_MAC_LANG_CHINESE_TRAD =19 +}; + +#ifdef __cplusplus +} +#endif + +#endif // __STB_INCLUDE_STB_TRUETYPE_H__ + +/////////////////////////////////////////////////////////////////////////////// +/////////////////////////////////////////////////////////////////////////////// +//// +//// IMPLEMENTATION +//// +//// + +#ifdef STB_TRUETYPE_IMPLEMENTATION + +#ifndef STBTT_MAX_OVERSAMPLE +#define STBTT_MAX_OVERSAMPLE 8 +#endif + +#if STBTT_MAX_OVERSAMPLE > 255 +#error "STBTT_MAX_OVERSAMPLE cannot be > 255" +#endif + +typedef int stbtt__test_oversample_pow2[(STBTT_MAX_OVERSAMPLE & (STBTT_MAX_OVERSAMPLE-1)) == 0 ? 1 : -1]; + +#ifndef STBTT_RASTERIZER_VERSION +#define STBTT_RASTERIZER_VERSION 2 +#endif + +#ifdef _MSC_VER +#define STBTT__NOTUSED(v) (void)(v) +#else +#define STBTT__NOTUSED(v) (void)sizeof(v) +#endif + +////////////////////////////////////////////////////////////////////////// +// +// stbtt__buf helpers to parse data from file +// + +static stbtt_uint8 stbtt__buf_get8(stbtt__buf *b) +{ + if (b->cursor >= b->size) + return 0; + return b->data[b->cursor++]; +} + +static stbtt_uint8 stbtt__buf_peek8(stbtt__buf *b) +{ + if (b->cursor >= b->size) + return 0; + return b->data[b->cursor]; +} + +static void stbtt__buf_seek(stbtt__buf *b, int o) +{ + STBTT_assert(!(o > b->size || o < 0)); + b->cursor = (o > b->size || o < 0) ? b->size : o; +} + +static void stbtt__buf_skip(stbtt__buf *b, int o) +{ + stbtt__buf_seek(b, b->cursor + o); +} + +static stbtt_uint32 stbtt__buf_get(stbtt__buf *b, int n) +{ + stbtt_uint32 v = 0; + int i; + STBTT_assert(n >= 1 && n <= 4); + for (i = 0; i < n; i++) + v = (v << 8) | stbtt__buf_get8(b); + return v; +} + +static stbtt__buf stbtt__new_buf(const void *p, size_t size) +{ + stbtt__buf r; + STBTT_assert(size < 0x40000000); + r.data = (stbtt_uint8*) p; + r.size = (int) size; + r.cursor = 0; + return r; +} + +#define stbtt__buf_get16(b) stbtt__buf_get((b), 2) +#define stbtt__buf_get32(b) stbtt__buf_get((b), 4) + +static stbtt__buf stbtt__buf_range(const stbtt__buf *b, int o, int s) +{ + stbtt__buf r = stbtt__new_buf(NULL, 0); + if (o < 0 || s < 0 || o > b->size || s > b->size - o) return r; + r.data = b->data + o; + r.size = s; + return r; +} + +static stbtt__buf stbtt__cff_get_index(stbtt__buf *b) +{ + int count, start, offsize; + start = b->cursor; + count = stbtt__buf_get16(b); + if (count) { + offsize = stbtt__buf_get8(b); + STBTT_assert(offsize >= 1 && offsize <= 4); + stbtt__buf_skip(b, offsize * count); + stbtt__buf_skip(b, stbtt__buf_get(b, offsize) - 1); + } + return stbtt__buf_range(b, start, b->cursor - start); +} + +static stbtt_uint32 stbtt__cff_int(stbtt__buf *b) +{ + int b0 = stbtt__buf_get8(b); + if (b0 >= 32 && b0 <= 246) return b0 - 139; + else if (b0 >= 247 && b0 <= 250) return (b0 - 247)*256 + stbtt__buf_get8(b) + 108; + else if (b0 >= 251 && b0 <= 254) return -(b0 - 251)*256 - stbtt__buf_get8(b) - 108; + else if (b0 == 28) return stbtt__buf_get16(b); + else if (b0 == 29) return stbtt__buf_get32(b); + STBTT_assert(0); + return 0; +} + +static void stbtt__cff_skip_operand(stbtt__buf *b) { + int v, b0 = stbtt__buf_peek8(b); + STBTT_assert(b0 >= 28); + if (b0 == 30) { + stbtt__buf_skip(b, 1); + while (b->cursor < b->size) { + v = stbtt__buf_get8(b); + if ((v & 0xF) == 0xF || (v >> 4) == 0xF) + break; + } + } else { + stbtt__cff_int(b); + } +} + +static stbtt__buf stbtt__dict_get(stbtt__buf *b, int key) +{ + stbtt__buf_seek(b, 0); + while (b->cursor < b->size) { + int start = b->cursor, end, op; + while (stbtt__buf_peek8(b) >= 28) + stbtt__cff_skip_operand(b); + end = b->cursor; + op = stbtt__buf_get8(b); + if (op == 12) op = stbtt__buf_get8(b) | 0x100; + if (op == key) return stbtt__buf_range(b, start, end-start); + } + return stbtt__buf_range(b, 0, 0); +} + +static void stbtt__dict_get_ints(stbtt__buf *b, int key, int outcount, stbtt_uint32 *out) +{ + int i; + stbtt__buf operands = stbtt__dict_get(b, key); + for (i = 0; i < outcount && operands.cursor < operands.size; i++) + out[i] = stbtt__cff_int(&operands); +} + +static int stbtt__cff_index_count(stbtt__buf *b) +{ + stbtt__buf_seek(b, 0); + return stbtt__buf_get16(b); +} + +static stbtt__buf stbtt__cff_index_get(stbtt__buf b, int i) +{ + int count, offsize, start, end; + stbtt__buf_seek(&b, 0); + count = stbtt__buf_get16(&b); + offsize = stbtt__buf_get8(&b); + STBTT_assert(i >= 0 && i < count); + STBTT_assert(offsize >= 1 && offsize <= 4); + stbtt__buf_skip(&b, i*offsize); + start = stbtt__buf_get(&b, offsize); + end = stbtt__buf_get(&b, offsize); + return stbtt__buf_range(&b, 2+(count+1)*offsize+start, end - start); +} + +////////////////////////////////////////////////////////////////////////// +// +// accessors to parse data from file +// + +// on platforms that don't allow misaligned reads, if we want to allow +// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE + +#define ttBYTE(p) (* (stbtt_uint8 *) (p)) +#define ttCHAR(p) (* (stbtt_int8 *) (p)) +#define ttFixed(p) ttLONG(p) + +static stbtt_uint16 ttUSHORT(stbtt_uint8 *p) { return p[0]*256 + p[1]; } +static stbtt_int16 ttSHORT(stbtt_uint8 *p) { return p[0]*256 + p[1]; } +static stbtt_uint32 ttULONG(stbtt_uint8 *p) { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; } +static stbtt_int32 ttLONG(stbtt_uint8 *p) { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; } + +#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3)) +#define stbtt_tag(p,str) stbtt_tag4(p,str[0],str[1],str[2],str[3]) + +static int stbtt__isfont(stbtt_uint8 *font) +{ + // check the version number + if (stbtt_tag4(font, '1',0,0,0)) return 1; // TrueType 1 + if (stbtt_tag(font, "typ1")) return 1; // TrueType with type 1 font -- we don't support this! + if (stbtt_tag(font, "OTTO")) return 1; // OpenType with CFF + if (stbtt_tag4(font, 0,1,0,0)) return 1; // OpenType 1.0 + if (stbtt_tag(font, "true")) return 1; // Apple specification for TrueType fonts + return 0; +} + +// @OPTIMIZE: binary search +static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, const char *tag) +{ + stbtt_int32 num_tables = ttUSHORT(data+fontstart+4); + stbtt_uint32 tabledir = fontstart + 12; + stbtt_int32 i; + for (i=0; i < num_tables; ++i) { + stbtt_uint32 loc = tabledir + 16*i; + if (stbtt_tag(data+loc+0, tag)) + return ttULONG(data+loc+8); + } + return 0; +} + +static int stbtt_GetFontOffsetForIndex_internal(unsigned char *font_collection, int index) +{ + // if it's just a font, there's only one valid index + if (stbtt__isfont(font_collection)) + return index == 0 ? 0 : -1; + + // check if it's a TTC + if (stbtt_tag(font_collection, "ttcf")) { + // version 1? + if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) { + stbtt_int32 n = ttLONG(font_collection+8); + if (index >= n) + return -1; + return ttULONG(font_collection+12+index*4); + } + } + return -1; +} + +static int stbtt_GetNumberOfFonts_internal(unsigned char *font_collection) +{ + // if it's just a font, there's only one valid font + if (stbtt__isfont(font_collection)) + return 1; + + // check if it's a TTC + if (stbtt_tag(font_collection, "ttcf")) { + // version 1? + if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) { + return ttLONG(font_collection+8); + } + } + return 0; +} + +static stbtt__buf stbtt__get_subrs(stbtt__buf cff, stbtt__buf fontdict) +{ + stbtt_uint32 subrsoff = 0, private_loc[2] = { 0, 0 }; + stbtt__buf pdict; + stbtt__dict_get_ints(&fontdict, 18, 2, private_loc); + if (!private_loc[1] || !private_loc[0]) return stbtt__new_buf(NULL, 0); + pdict = stbtt__buf_range(&cff, private_loc[1], private_loc[0]); + stbtt__dict_get_ints(&pdict, 19, 1, &subrsoff); + if (!subrsoff) return stbtt__new_buf(NULL, 0); + stbtt__buf_seek(&cff, private_loc[1]+subrsoff); + return stbtt__cff_get_index(&cff); +} + +// since most people won't use this, find this table the first time it's needed +static int stbtt__get_svg(stbtt_fontinfo *info) +{ + stbtt_uint32 t; + if (info->svg < 0) { + t = stbtt__find_table(info->data, info->fontstart, "SVG "); + if (t) { + stbtt_uint32 offset = ttULONG(info->data + t + 2); + info->svg = t + offset; + } else { + info->svg = 0; + } + } + return info->svg; +} + +static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart) +{ + stbtt_uint32 cmap, t; + stbtt_int32 i,numTables; + + info->data = data; + info->fontstart = fontstart; + info->cff = stbtt__new_buf(NULL, 0); + + cmap = stbtt__find_table(data, fontstart, "cmap"); // required + info->loca = stbtt__find_table(data, fontstart, "loca"); // required + info->head = stbtt__find_table(data, fontstart, "head"); // required + info->glyf = stbtt__find_table(data, fontstart, "glyf"); // required + info->hhea = stbtt__find_table(data, fontstart, "hhea"); // required + info->hmtx = stbtt__find_table(data, fontstart, "hmtx"); // required + info->kern = stbtt__find_table(data, fontstart, "kern"); // not required + info->gpos = stbtt__find_table(data, fontstart, "GPOS"); // not required + + if (!cmap || !info->head || !info->hhea || !info->hmtx) + return 0; + if (info->glyf) { + // required for truetype + if (!info->loca) return 0; + } else { + // initialization for CFF / Type2 fonts (OTF) + stbtt__buf b, topdict, topdictidx; + stbtt_uint32 cstype = 2, charstrings = 0, fdarrayoff = 0, fdselectoff = 0; + stbtt_uint32 cff; + + cff = stbtt__find_table(data, fontstart, "CFF "); + if (!cff) return 0; + + info->fontdicts = stbtt__new_buf(NULL, 0); + info->fdselect = stbtt__new_buf(NULL, 0); + + // @TODO this should use size from table (not 512MB) + info->cff = stbtt__new_buf(data+cff, 512*1024*1024); + b = info->cff; + + // read the header + stbtt__buf_skip(&b, 2); + stbtt__buf_seek(&b, stbtt__buf_get8(&b)); // hdrsize + + // @TODO the name INDEX could list multiple fonts, + // but we just use the first one. + stbtt__cff_get_index(&b); // name INDEX + topdictidx = stbtt__cff_get_index(&b); + topdict = stbtt__cff_index_get(topdictidx, 0); + stbtt__cff_get_index(&b); // string INDEX + info->gsubrs = stbtt__cff_get_index(&b); + + stbtt__dict_get_ints(&topdict, 17, 1, &charstrings); + stbtt__dict_get_ints(&topdict, 0x100 | 6, 1, &cstype); + stbtt__dict_get_ints(&topdict, 0x100 | 36, 1, &fdarrayoff); + stbtt__dict_get_ints(&topdict, 0x100 | 37, 1, &fdselectoff); + info->subrs = stbtt__get_subrs(b, topdict); + + // we only support Type 2 charstrings + if (cstype != 2) return 0; + if (charstrings == 0) return 0; + + if (fdarrayoff) { + // looks like a CID font + if (!fdselectoff) return 0; + stbtt__buf_seek(&b, fdarrayoff); + info->fontdicts = stbtt__cff_get_index(&b); + info->fdselect = stbtt__buf_range(&b, fdselectoff, b.size-fdselectoff); + } + + stbtt__buf_seek(&b, charstrings); + info->charstrings = stbtt__cff_get_index(&b); + } + + t = stbtt__find_table(data, fontstart, "maxp"); + if (t) + info->numGlyphs = ttUSHORT(data+t+4); + else + info->numGlyphs = 0xffff; + + info->svg = -1; + + // find a cmap encoding table we understand *now* to avoid searching + // later. (todo: could make this installable) + // the same regardless of glyph. + numTables = ttUSHORT(data + cmap + 2); + info->index_map = 0; + for (i=0; i < numTables; ++i) { + stbtt_uint32 encoding_record = cmap + 4 + 8 * i; + // find an encoding we understand: + switch(ttUSHORT(data+encoding_record)) { + case STBTT_PLATFORM_ID_MICROSOFT: + switch (ttUSHORT(data+encoding_record+2)) { + case STBTT_MS_EID_UNICODE_BMP: + case STBTT_MS_EID_UNICODE_FULL: + // MS/Unicode + info->index_map = cmap + ttULONG(data+encoding_record+4); + break; + } + break; + case STBTT_PLATFORM_ID_UNICODE: + // Mac/iOS has these + // all the encodingIDs are unicode, so we don't bother to check it + info->index_map = cmap + ttULONG(data+encoding_record+4); + break; + } + } + if (info->index_map == 0) + return 0; + + info->indexToLocFormat = ttUSHORT(data+info->head + 50); + return 1; +} + +STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint) +{ + stbtt_uint8 *data = info->data; + stbtt_uint32 index_map = info->index_map; + + stbtt_uint16 format = ttUSHORT(data + index_map + 0); + if (format == 0) { // apple byte encoding + stbtt_int32 bytes = ttUSHORT(data + index_map + 2); + if (unicode_codepoint < bytes-6) + return ttBYTE(data + index_map + 6 + unicode_codepoint); + return 0; + } else if (format == 6) { + stbtt_uint32 first = ttUSHORT(data + index_map + 6); + stbtt_uint32 count = ttUSHORT(data + index_map + 8); + if ((stbtt_uint32) unicode_codepoint >= first && (stbtt_uint32) unicode_codepoint < first+count) + return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first)*2); + return 0; + } else if (format == 2) { + STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean + return 0; + } else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges + stbtt_uint16 segcount = ttUSHORT(data+index_map+6) >> 1; + stbtt_uint16 searchRange = ttUSHORT(data+index_map+8) >> 1; + stbtt_uint16 entrySelector = ttUSHORT(data+index_map+10); + stbtt_uint16 rangeShift = ttUSHORT(data+index_map+12) >> 1; + + // do a binary search of the segments + stbtt_uint32 endCount = index_map + 14; + stbtt_uint32 search = endCount; + + if (unicode_codepoint > 0xffff) + return 0; + + // they lie from endCount .. endCount + segCount + // but searchRange is the nearest power of two, so... + if (unicode_codepoint >= ttUSHORT(data + search + rangeShift*2)) + search += rangeShift*2; + + // now decrement to bias correctly to find smallest + search -= 2; + while (entrySelector) { + stbtt_uint16 end; + searchRange >>= 1; + end = ttUSHORT(data + search + searchRange*2); + if (unicode_codepoint > end) + search += searchRange*2; + --entrySelector; + } + search += 2; + + { + stbtt_uint16 offset, start, last; + stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1); + + start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item); + last = ttUSHORT(data + endCount + 2*item); + if (unicode_codepoint < start || unicode_codepoint > last) + return 0; + + offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item); + if (offset == 0) + return (stbtt_uint16) (unicode_codepoint + ttSHORT(data + index_map + 14 + segcount*4 + 2 + 2*item)); + + return ttUSHORT(data + offset + (unicode_codepoint-start)*2 + index_map + 14 + segcount*6 + 2 + 2*item); + } + } else if (format == 12 || format == 13) { + stbtt_uint32 ngroups = ttULONG(data+index_map+12); + stbtt_int32 low,high; + low = 0; high = (stbtt_int32)ngroups; + // Binary search the right group. + while (low < high) { + stbtt_int32 mid = low + ((high-low) >> 1); // rounds down, so low <= mid < high + stbtt_uint32 start_char = ttULONG(data+index_map+16+mid*12); + stbtt_uint32 end_char = ttULONG(data+index_map+16+mid*12+4); + if ((stbtt_uint32) unicode_codepoint < start_char) + high = mid; + else if ((stbtt_uint32) unicode_codepoint > end_char) + low = mid+1; + else { + stbtt_uint32 start_glyph = ttULONG(data+index_map+16+mid*12+8); + if (format == 12) + return start_glyph + unicode_codepoint-start_char; + else // format == 13 + return start_glyph; + } + } + return 0; // not found + } + // @TODO + STBTT_assert(0); + return 0; +} + +STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices) +{ + return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices); +} + +static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy) +{ + v->type = type; + v->x = (stbtt_int16) x; + v->y = (stbtt_int16) y; + v->cx = (stbtt_int16) cx; + v->cy = (stbtt_int16) cy; +} + +static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index) +{ + int g1,g2; + + STBTT_assert(!info->cff.size); + + if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range + if (info->indexToLocFormat >= 2) return -1; // unknown index->glyph map format + + if (info->indexToLocFormat == 0) { + g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2; + g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2; + } else { + g1 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4); + g2 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4 + 4); + } + + return g1==g2 ? -1 : g1; // if length is 0, return -1 +} + +static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1); + +STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1) +{ + if (info->cff.size) { + stbtt__GetGlyphInfoT2(info, glyph_index, x0, y0, x1, y1); + } else { + int g = stbtt__GetGlyfOffset(info, glyph_index); + if (g < 0) return 0; + + if (x0) *x0 = ttSHORT(info->data + g + 2); + if (y0) *y0 = ttSHORT(info->data + g + 4); + if (x1) *x1 = ttSHORT(info->data + g + 6); + if (y1) *y1 = ttSHORT(info->data + g + 8); + } + return 1; +} + +STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1) +{ + return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info,codepoint), x0,y0,x1,y1); +} + +STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index) +{ + stbtt_int16 numberOfContours; + int g; + if (info->cff.size) + return stbtt__GetGlyphInfoT2(info, glyph_index, NULL, NULL, NULL, NULL) == 0; + g = stbtt__GetGlyfOffset(info, glyph_index); + if (g < 0) return 1; + numberOfContours = ttSHORT(info->data + g); + return numberOfContours == 0; +} + +static int stbtt__close_shape(stbtt_vertex *vertices, int num_vertices, int was_off, int start_off, + stbtt_int32 sx, stbtt_int32 sy, stbtt_int32 scx, stbtt_int32 scy, stbtt_int32 cx, stbtt_int32 cy) +{ + if (start_off) { + if (was_off) + stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+scx)>>1, (cy+scy)>>1, cx,cy); + stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx,sy,scx,scy); + } else { + if (was_off) + stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy); + else + stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0); + } + return num_vertices; +} + +static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices) +{ + stbtt_int16 numberOfContours; + stbtt_uint8 *endPtsOfContours; + stbtt_uint8 *data = info->data; + stbtt_vertex *vertices=0; + int num_vertices=0; + int g = stbtt__GetGlyfOffset(info, glyph_index); + + *pvertices = NULL; + + if (g < 0) return 0; + + numberOfContours = ttSHORT(data + g); + + if (numberOfContours > 0) { + stbtt_uint8 flags=0,flagcount; + stbtt_int32 ins, i,j=0,m,n, next_move, was_off=0, off, start_off=0; + stbtt_int32 x,y,cx,cy,sx,sy, scx,scy; + stbtt_uint8 *points; + endPtsOfContours = (data + g + 10); + ins = ttUSHORT(data + g + 10 + numberOfContours * 2); + points = data + g + 10 + numberOfContours * 2 + 2 + ins; + + n = 1+ttUSHORT(endPtsOfContours + numberOfContours*2-2); + + m = n + 2*numberOfContours; // a loose bound on how many vertices we might need + vertices = (stbtt_vertex *) STBTT_malloc(m * sizeof(vertices[0]), info->userdata); + if (vertices == 0) + return 0; + + next_move = 0; + flagcount=0; + + // in first pass, we load uninterpreted data into the allocated array + // above, shifted to the end of the array so we won't overwrite it when + // we create our final data starting from the front + + off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated + + // first load flags + + for (i=0; i < n; ++i) { + if (flagcount == 0) { + flags = *points++; + if (flags & 8) + flagcount = *points++; + } else + --flagcount; + vertices[off+i].type = flags; + } + + // now load x coordinates + x=0; + for (i=0; i < n; ++i) { + flags = vertices[off+i].type; + if (flags & 2) { + stbtt_int16 dx = *points++; + x += (flags & 16) ? dx : -dx; // ??? + } else { + if (!(flags & 16)) { + x = x + (stbtt_int16) (points[0]*256 + points[1]); + points += 2; + } + } + vertices[off+i].x = (stbtt_int16) x; + } + + // now load y coordinates + y=0; + for (i=0; i < n; ++i) { + flags = vertices[off+i].type; + if (flags & 4) { + stbtt_int16 dy = *points++; + y += (flags & 32) ? dy : -dy; // ??? + } else { + if (!(flags & 32)) { + y = y + (stbtt_int16) (points[0]*256 + points[1]); + points += 2; + } + } + vertices[off+i].y = (stbtt_int16) y; + } + + // now convert them to our format + num_vertices=0; + sx = sy = cx = cy = scx = scy = 0; + for (i=0; i < n; ++i) { + flags = vertices[off+i].type; + x = (stbtt_int16) vertices[off+i].x; + y = (stbtt_int16) vertices[off+i].y; + + if (next_move == i) { + if (i != 0) + num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy); + + // now start the new one + start_off = !(flags & 1); + if (start_off) { + // if we start off with an off-curve point, then when we need to find a point on the curve + // where we can start, and we need to save some state for when we wraparound. + scx = x; + scy = y; + if (!(vertices[off+i+1].type & 1)) { + // next point is also a curve point, so interpolate an on-point curve + sx = (x + (stbtt_int32) vertices[off+i+1].x) >> 1; + sy = (y + (stbtt_int32) vertices[off+i+1].y) >> 1; + } else { + // otherwise just use the next point as our start point + sx = (stbtt_int32) vertices[off+i+1].x; + sy = (stbtt_int32) vertices[off+i+1].y; + ++i; // we're using point i+1 as the starting point, so skip it + } + } else { + sx = x; + sy = y; + } + stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove,sx,sy,0,0); + was_off = 0; + next_move = 1 + ttUSHORT(endPtsOfContours+j*2); + ++j; + } else { + if (!(flags & 1)) { // if it's a curve + if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint + stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+x)>>1, (cy+y)>>1, cx, cy); + cx = x; + cy = y; + was_off = 1; + } else { + if (was_off) + stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x,y, cx, cy); + else + stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x,y,0,0); + was_off = 0; + } + } + } + num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy); + } else if (numberOfContours < 0) { + // Compound shapes. + int more = 1; + stbtt_uint8 *comp = data + g + 10; + num_vertices = 0; + vertices = 0; + while (more) { + stbtt_uint16 flags, gidx; + int comp_num_verts = 0, i; + stbtt_vertex *comp_verts = 0, *tmp = 0; + float mtx[6] = {1,0,0,1,0,0}, m, n; + + flags = ttSHORT(comp); comp+=2; + gidx = ttSHORT(comp); comp+=2; + + if (flags & 2) { // XY values + if (flags & 1) { // shorts + mtx[4] = ttSHORT(comp); comp+=2; + mtx[5] = ttSHORT(comp); comp+=2; + } else { + mtx[4] = ttCHAR(comp); comp+=1; + mtx[5] = ttCHAR(comp); comp+=1; + } + } + else { + // @TODO handle matching point + STBTT_assert(0); + } + if (flags & (1<<3)) { // WE_HAVE_A_SCALE + mtx[0] = mtx[3] = ttSHORT(comp)/16384.0f; comp+=2; + mtx[1] = mtx[2] = 0; + } else if (flags & (1<<6)) { // WE_HAVE_AN_X_AND_YSCALE + mtx[0] = ttSHORT(comp)/16384.0f; comp+=2; + mtx[1] = mtx[2] = 0; + mtx[3] = ttSHORT(comp)/16384.0f; comp+=2; + } else if (flags & (1<<7)) { // WE_HAVE_A_TWO_BY_TWO + mtx[0] = ttSHORT(comp)/16384.0f; comp+=2; + mtx[1] = ttSHORT(comp)/16384.0f; comp+=2; + mtx[2] = ttSHORT(comp)/16384.0f; comp+=2; + mtx[3] = ttSHORT(comp)/16384.0f; comp+=2; + } + + // Find transformation scales. + m = (float) STBTT_sqrt(mtx[0]*mtx[0] + mtx[1]*mtx[1]); + n = (float) STBTT_sqrt(mtx[2]*mtx[2] + mtx[3]*mtx[3]); + + // Get indexed glyph. + comp_num_verts = stbtt_GetGlyphShape(info, gidx, &comp_verts); + if (comp_num_verts > 0) { + // Transform vertices. + for (i = 0; i < comp_num_verts; ++i) { + stbtt_vertex* v = &comp_verts[i]; + stbtt_vertex_type x,y; + x=v->x; y=v->y; + v->x = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4])); + v->y = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5])); + x=v->cx; y=v->cy; + v->cx = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4])); + v->cy = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5])); + } + // Append vertices. + tmp = (stbtt_vertex*)STBTT_malloc((num_vertices+comp_num_verts)*sizeof(stbtt_vertex), info->userdata); + if (!tmp) { + if (vertices) STBTT_free(vertices, info->userdata); + if (comp_verts) STBTT_free(comp_verts, info->userdata); + return 0; + } + if (num_vertices > 0 && vertices) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex)); + STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex)); + if (vertices) STBTT_free(vertices, info->userdata); + vertices = tmp; + STBTT_free(comp_verts, info->userdata); + num_vertices += comp_num_verts; + } + // More components ? + more = flags & (1<<5); + } + } else { + // numberOfCounters == 0, do nothing + } + + *pvertices = vertices; + return num_vertices; +} + +typedef struct +{ + int bounds; + int started; + float first_x, first_y; + float x, y; + stbtt_int32 min_x, max_x, min_y, max_y; + + stbtt_vertex *pvertices; + int num_vertices; +} stbtt__csctx; + +#define STBTT__CSCTX_INIT(bounds) {bounds,0, 0,0, 0,0, 0,0,0,0, NULL, 0} + +static void stbtt__track_vertex(stbtt__csctx *c, stbtt_int32 x, stbtt_int32 y) +{ + if (x > c->max_x || !c->started) c->max_x = x; + if (y > c->max_y || !c->started) c->max_y = y; + if (x < c->min_x || !c->started) c->min_x = x; + if (y < c->min_y || !c->started) c->min_y = y; + c->started = 1; +} + +static void stbtt__csctx_v(stbtt__csctx *c, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy, stbtt_int32 cx1, stbtt_int32 cy1) +{ + if (c->bounds) { + stbtt__track_vertex(c, x, y); + if (type == STBTT_vcubic) { + stbtt__track_vertex(c, cx, cy); + stbtt__track_vertex(c, cx1, cy1); + } + } else { + stbtt_setvertex(&c->pvertices[c->num_vertices], type, x, y, cx, cy); + c->pvertices[c->num_vertices].cx1 = (stbtt_int16) cx1; + c->pvertices[c->num_vertices].cy1 = (stbtt_int16) cy1; + } + c->num_vertices++; +} + +static void stbtt__csctx_close_shape(stbtt__csctx *ctx) +{ + if (ctx->first_x != ctx->x || ctx->first_y != ctx->y) + stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->first_x, (int)ctx->first_y, 0, 0, 0, 0); +} + +static void stbtt__csctx_rmove_to(stbtt__csctx *ctx, float dx, float dy) +{ + stbtt__csctx_close_shape(ctx); + ctx->first_x = ctx->x = ctx->x + dx; + ctx->first_y = ctx->y = ctx->y + dy; + stbtt__csctx_v(ctx, STBTT_vmove, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0); +} + +static void stbtt__csctx_rline_to(stbtt__csctx *ctx, float dx, float dy) +{ + ctx->x += dx; + ctx->y += dy; + stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0); +} + +static void stbtt__csctx_rccurve_to(stbtt__csctx *ctx, float dx1, float dy1, float dx2, float dy2, float dx3, float dy3) +{ + float cx1 = ctx->x + dx1; + float cy1 = ctx->y + dy1; + float cx2 = cx1 + dx2; + float cy2 = cy1 + dy2; + ctx->x = cx2 + dx3; + ctx->y = cy2 + dy3; + stbtt__csctx_v(ctx, STBTT_vcubic, (int)ctx->x, (int)ctx->y, (int)cx1, (int)cy1, (int)cx2, (int)cy2); +} + +static stbtt__buf stbtt__get_subr(stbtt__buf idx, int n) +{ + int count = stbtt__cff_index_count(&idx); + int bias = 107; + if (count >= 33900) + bias = 32768; + else if (count >= 1240) + bias = 1131; + n += bias; + if (n < 0 || n >= count) + return stbtt__new_buf(NULL, 0); + return stbtt__cff_index_get(idx, n); +} + +static stbtt__buf stbtt__cid_get_glyph_subrs(const stbtt_fontinfo *info, int glyph_index) +{ + stbtt__buf fdselect = info->fdselect; + int nranges, start, end, v, fmt, fdselector = -1, i; + + stbtt__buf_seek(&fdselect, 0); + fmt = stbtt__buf_get8(&fdselect); + if (fmt == 0) { + // untested + stbtt__buf_skip(&fdselect, glyph_index); + fdselector = stbtt__buf_get8(&fdselect); + } else if (fmt == 3) { + nranges = stbtt__buf_get16(&fdselect); + start = stbtt__buf_get16(&fdselect); + for (i = 0; i < nranges; i++) { + v = stbtt__buf_get8(&fdselect); + end = stbtt__buf_get16(&fdselect); + if (glyph_index >= start && glyph_index < end) { + fdselector = v; + break; + } + start = end; + } + } + if (fdselector == -1) stbtt__new_buf(NULL, 0); + return stbtt__get_subrs(info->cff, stbtt__cff_index_get(info->fontdicts, fdselector)); +} + +static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, stbtt__csctx *c) +{ + int in_header = 1, maskbits = 0, subr_stack_height = 0, sp = 0, v, i, b0; + int has_subrs = 0, clear_stack; + float s[48]; + stbtt__buf subr_stack[10], subrs = info->subrs, b; + float f; + +#define STBTT__CSERR(s) (0) + + // this currently ignores the initial width value, which isn't needed if we have hmtx + b = stbtt__cff_index_get(info->charstrings, glyph_index); + while (b.cursor < b.size) { + i = 0; + clear_stack = 1; + b0 = stbtt__buf_get8(&b); + switch (b0) { + // @TODO implement hinting + case 0x13: // hintmask + case 0x14: // cntrmask + if (in_header) + maskbits += (sp / 2); // implicit "vstem" + in_header = 0; + stbtt__buf_skip(&b, (maskbits + 7) / 8); + break; + + case 0x01: // hstem + case 0x03: // vstem + case 0x12: // hstemhm + case 0x17: // vstemhm + maskbits += (sp / 2); + break; + + case 0x15: // rmoveto + in_header = 0; + if (sp < 2) return STBTT__CSERR("rmoveto stack"); + stbtt__csctx_rmove_to(c, s[sp-2], s[sp-1]); + break; + case 0x04: // vmoveto + in_header = 0; + if (sp < 1) return STBTT__CSERR("vmoveto stack"); + stbtt__csctx_rmove_to(c, 0, s[sp-1]); + break; + case 0x16: // hmoveto + in_header = 0; + if (sp < 1) return STBTT__CSERR("hmoveto stack"); + stbtt__csctx_rmove_to(c, s[sp-1], 0); + break; + + case 0x05: // rlineto + if (sp < 2) return STBTT__CSERR("rlineto stack"); + for (; i + 1 < sp; i += 2) + stbtt__csctx_rline_to(c, s[i], s[i+1]); + break; + + // hlineto/vlineto and vhcurveto/hvcurveto alternate horizontal and vertical + // starting from a different place. + + case 0x07: // vlineto + if (sp < 1) return STBTT__CSERR("vlineto stack"); + goto vlineto; + case 0x06: // hlineto + if (sp < 1) return STBTT__CSERR("hlineto stack"); + for (;;) { + if (i >= sp) break; + stbtt__csctx_rline_to(c, s[i], 0); + i++; + vlineto: + if (i >= sp) break; + stbtt__csctx_rline_to(c, 0, s[i]); + i++; + } + break; + + case 0x1F: // hvcurveto + if (sp < 4) return STBTT__CSERR("hvcurveto stack"); + goto hvcurveto; + case 0x1E: // vhcurveto + if (sp < 4) return STBTT__CSERR("vhcurveto stack"); + for (;;) { + if (i + 3 >= sp) break; + stbtt__csctx_rccurve_to(c, 0, s[i], s[i+1], s[i+2], s[i+3], (sp - i == 5) ? s[i + 4] : 0.0f); + i += 4; + hvcurveto: + if (i + 3 >= sp) break; + stbtt__csctx_rccurve_to(c, s[i], 0, s[i+1], s[i+2], (sp - i == 5) ? s[i+4] : 0.0f, s[i+3]); + i += 4; + } + break; + + case 0x08: // rrcurveto + if (sp < 6) return STBTT__CSERR("rcurveline stack"); + for (; i + 5 < sp; i += 6) + stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]); + break; + + case 0x18: // rcurveline + if (sp < 8) return STBTT__CSERR("rcurveline stack"); + for (; i + 5 < sp - 2; i += 6) + stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]); + if (i + 1 >= sp) return STBTT__CSERR("rcurveline stack"); + stbtt__csctx_rline_to(c, s[i], s[i+1]); + break; + + case 0x19: // rlinecurve + if (sp < 8) return STBTT__CSERR("rlinecurve stack"); + for (; i + 1 < sp - 6; i += 2) + stbtt__csctx_rline_to(c, s[i], s[i+1]); + if (i + 5 >= sp) return STBTT__CSERR("rlinecurve stack"); + stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]); + break; + + case 0x1A: // vvcurveto + case 0x1B: // hhcurveto + if (sp < 4) return STBTT__CSERR("(vv|hh)curveto stack"); + f = 0.0; + if (sp & 1) { f = s[i]; i++; } + for (; i + 3 < sp; i += 4) { + if (b0 == 0x1B) + stbtt__csctx_rccurve_to(c, s[i], f, s[i+1], s[i+2], s[i+3], 0.0); + else + stbtt__csctx_rccurve_to(c, f, s[i], s[i+1], s[i+2], 0.0, s[i+3]); + f = 0.0; + } + break; + + case 0x0A: // callsubr + if (!has_subrs) { + if (info->fdselect.size) + subrs = stbtt__cid_get_glyph_subrs(info, glyph_index); + has_subrs = 1; + } + // FALLTHROUGH + case 0x1D: // callgsubr + if (sp < 1) return STBTT__CSERR("call(g|)subr stack"); + v = (int) s[--sp]; + if (subr_stack_height >= 10) return STBTT__CSERR("recursion limit"); + subr_stack[subr_stack_height++] = b; + b = stbtt__get_subr(b0 == 0x0A ? subrs : info->gsubrs, v); + if (b.size == 0) return STBTT__CSERR("subr not found"); + b.cursor = 0; + clear_stack = 0; + break; + + case 0x0B: // return + if (subr_stack_height <= 0) return STBTT__CSERR("return outside subr"); + b = subr_stack[--subr_stack_height]; + clear_stack = 0; + break; + + case 0x0E: // endchar + stbtt__csctx_close_shape(c); + return 1; + + case 0x0C: { // two-byte escape + float dx1, dx2, dx3, dx4, dx5, dx6, dy1, dy2, dy3, dy4, dy5, dy6; + float dx, dy; + int b1 = stbtt__buf_get8(&b); + switch (b1) { + // @TODO These "flex" implementations ignore the flex-depth and resolution, + // and always draw beziers. + case 0x22: // hflex + if (sp < 7) return STBTT__CSERR("hflex stack"); + dx1 = s[0]; + dx2 = s[1]; + dy2 = s[2]; + dx3 = s[3]; + dx4 = s[4]; + dx5 = s[5]; + dx6 = s[6]; + stbtt__csctx_rccurve_to(c, dx1, 0, dx2, dy2, dx3, 0); + stbtt__csctx_rccurve_to(c, dx4, 0, dx5, -dy2, dx6, 0); + break; + + case 0x23: // flex + if (sp < 13) return STBTT__CSERR("flex stack"); + dx1 = s[0]; + dy1 = s[1]; + dx2 = s[2]; + dy2 = s[3]; + dx3 = s[4]; + dy3 = s[5]; + dx4 = s[6]; + dy4 = s[7]; + dx5 = s[8]; + dy5 = s[9]; + dx6 = s[10]; + dy6 = s[11]; + //fd is s[12] + stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3); + stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6); + break; + + case 0x24: // hflex1 + if (sp < 9) return STBTT__CSERR("hflex1 stack"); + dx1 = s[0]; + dy1 = s[1]; + dx2 = s[2]; + dy2 = s[3]; + dx3 = s[4]; + dx4 = s[5]; + dx5 = s[6]; + dy5 = s[7]; + dx6 = s[8]; + stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, 0); + stbtt__csctx_rccurve_to(c, dx4, 0, dx5, dy5, dx6, -(dy1+dy2+dy5)); + break; + + case 0x25: // flex1 + if (sp < 11) return STBTT__CSERR("flex1 stack"); + dx1 = s[0]; + dy1 = s[1]; + dx2 = s[2]; + dy2 = s[3]; + dx3 = s[4]; + dy3 = s[5]; + dx4 = s[6]; + dy4 = s[7]; + dx5 = s[8]; + dy5 = s[9]; + dx6 = dy6 = s[10]; + dx = dx1+dx2+dx3+dx4+dx5; + dy = dy1+dy2+dy3+dy4+dy5; + if (STBTT_fabs(dx) > STBTT_fabs(dy)) + dy6 = -dy; + else + dx6 = -dx; + stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3); + stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6); + break; + + default: + return STBTT__CSERR("unimplemented"); + } + } break; + + default: + if (b0 != 255 && b0 != 28 && b0 < 32) + return STBTT__CSERR("reserved operator"); + + // push immediate + if (b0 == 255) { + f = (float)(stbtt_int32)stbtt__buf_get32(&b) / 0x10000; + } else { + stbtt__buf_skip(&b, -1); + f = (float)(stbtt_int16)stbtt__cff_int(&b); + } + if (sp >= 48) return STBTT__CSERR("push stack overflow"); + s[sp++] = f; + clear_stack = 0; + break; + } + if (clear_stack) sp = 0; + } + return STBTT__CSERR("no endchar"); + +#undef STBTT__CSERR +} + +static int stbtt__GetGlyphShapeT2(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices) +{ + // runs the charstring twice, once to count and once to output (to avoid realloc) + stbtt__csctx count_ctx = STBTT__CSCTX_INIT(1); + stbtt__csctx output_ctx = STBTT__CSCTX_INIT(0); + if (stbtt__run_charstring(info, glyph_index, &count_ctx)) { + *pvertices = (stbtt_vertex*)STBTT_malloc(count_ctx.num_vertices*sizeof(stbtt_vertex), info->userdata); + output_ctx.pvertices = *pvertices; + if (stbtt__run_charstring(info, glyph_index, &output_ctx)) { + STBTT_assert(output_ctx.num_vertices == count_ctx.num_vertices); + return output_ctx.num_vertices; + } + } + *pvertices = NULL; + return 0; +} + +static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1) +{ + stbtt__csctx c = STBTT__CSCTX_INIT(1); + int r = stbtt__run_charstring(info, glyph_index, &c); + if (x0) *x0 = r ? c.min_x : 0; + if (y0) *y0 = r ? c.min_y : 0; + if (x1) *x1 = r ? c.max_x : 0; + if (y1) *y1 = r ? c.max_y : 0; + return r ? c.num_vertices : 0; +} + +STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices) +{ + if (!info->cff.size) + return stbtt__GetGlyphShapeTT(info, glyph_index, pvertices); + else + return stbtt__GetGlyphShapeT2(info, glyph_index, pvertices); +} + +STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing) +{ + stbtt_uint16 numOfLongHorMetrics = ttUSHORT(info->data+info->hhea + 34); + if (glyph_index < numOfLongHorMetrics) { + if (advanceWidth) *advanceWidth = ttSHORT(info->data + info->hmtx + 4*glyph_index); + if (leftSideBearing) *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*glyph_index + 2); + } else { + if (advanceWidth) *advanceWidth = ttSHORT(info->data + info->hmtx + 4*(numOfLongHorMetrics-1)); + if (leftSideBearing) *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*numOfLongHorMetrics + 2*(glyph_index - numOfLongHorMetrics)); + } +} + +STBTT_DEF int stbtt_GetKerningTableLength(const stbtt_fontinfo *info) +{ + stbtt_uint8 *data = info->data + info->kern; + + // we only look at the first table. it must be 'horizontal' and format 0. + if (!info->kern) + return 0; + if (ttUSHORT(data+2) < 1) // number of tables, need at least 1 + return 0; + if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format + return 0; + + return ttUSHORT(data+10); +} + +STBTT_DEF int stbtt_GetKerningTable(const stbtt_fontinfo *info, stbtt_kerningentry* table, int table_length) +{ + stbtt_uint8 *data = info->data + info->kern; + int k, length; + + // we only look at the first table. it must be 'horizontal' and format 0. + if (!info->kern) + return 0; + if (ttUSHORT(data+2) < 1) // number of tables, need at least 1 + return 0; + if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format + return 0; + + length = ttUSHORT(data+10); + if (table_length < length) + length = table_length; + + for (k = 0; k < length; k++) + { + table[k].glyph1 = ttUSHORT(data+18+(k*6)); + table[k].glyph2 = ttUSHORT(data+20+(k*6)); + table[k].advance = ttSHORT(data+22+(k*6)); + } + + return length; +} + +static int stbtt__GetGlyphKernInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2) +{ + stbtt_uint8 *data = info->data + info->kern; + stbtt_uint32 needle, straw; + int l, r, m; + + // we only look at the first table. it must be 'horizontal' and format 0. + if (!info->kern) + return 0; + if (ttUSHORT(data+2) < 1) // number of tables, need at least 1 + return 0; + if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format + return 0; + + l = 0; + r = ttUSHORT(data+10) - 1; + needle = glyph1 << 16 | glyph2; + while (l <= r) { + m = (l + r) >> 1; + straw = ttULONG(data+18+(m*6)); // note: unaligned read + if (needle < straw) + r = m - 1; + else if (needle > straw) + l = m + 1; + else + return ttSHORT(data+22+(m*6)); + } + return 0; +} + +static stbtt_int32 stbtt__GetCoverageIndex(stbtt_uint8 *coverageTable, int glyph) +{ + stbtt_uint16 coverageFormat = ttUSHORT(coverageTable); + switch (coverageFormat) { + case 1: { + stbtt_uint16 glyphCount = ttUSHORT(coverageTable + 2); + + // Binary search. + stbtt_int32 l=0, r=glyphCount-1, m; + int straw, needle=glyph; + while (l <= r) { + stbtt_uint8 *glyphArray = coverageTable + 4; + stbtt_uint16 glyphID; + m = (l + r) >> 1; + glyphID = ttUSHORT(glyphArray + 2 * m); + straw = glyphID; + if (needle < straw) + r = m - 1; + else if (needle > straw) + l = m + 1; + else { + return m; + } + } + break; + } + + case 2: { + stbtt_uint16 rangeCount = ttUSHORT(coverageTable + 2); + stbtt_uint8 *rangeArray = coverageTable + 4; + + // Binary search. + stbtt_int32 l=0, r=rangeCount-1, m; + int strawStart, strawEnd, needle=glyph; + while (l <= r) { + stbtt_uint8 *rangeRecord; + m = (l + r) >> 1; + rangeRecord = rangeArray + 6 * m; + strawStart = ttUSHORT(rangeRecord); + strawEnd = ttUSHORT(rangeRecord + 2); + if (needle < strawStart) + r = m - 1; + else if (needle > strawEnd) + l = m + 1; + else { + stbtt_uint16 startCoverageIndex = ttUSHORT(rangeRecord + 4); + return startCoverageIndex + glyph - strawStart; + } + } + break; + } + + default: return -1; // unsupported + } + + return -1; +} + +static stbtt_int32 stbtt__GetGlyphClass(stbtt_uint8 *classDefTable, int glyph) +{ + stbtt_uint16 classDefFormat = ttUSHORT(classDefTable); + switch (classDefFormat) + { + case 1: { + stbtt_uint16 startGlyphID = ttUSHORT(classDefTable + 2); + stbtt_uint16 glyphCount = ttUSHORT(classDefTable + 4); + stbtt_uint8 *classDef1ValueArray = classDefTable + 6; + + if (glyph >= startGlyphID && glyph < startGlyphID + glyphCount) + return (stbtt_int32)ttUSHORT(classDef1ValueArray + 2 * (glyph - startGlyphID)); + break; + } + + case 2: { + stbtt_uint16 classRangeCount = ttUSHORT(classDefTable + 2); + stbtt_uint8 *classRangeRecords = classDefTable + 4; + + // Binary search. + stbtt_int32 l=0, r=classRangeCount-1, m; + int strawStart, strawEnd, needle=glyph; + while (l <= r) { + stbtt_uint8 *classRangeRecord; + m = (l + r) >> 1; + classRangeRecord = classRangeRecords + 6 * m; + strawStart = ttUSHORT(classRangeRecord); + strawEnd = ttUSHORT(classRangeRecord + 2); + if (needle < strawStart) + r = m - 1; + else if (needle > strawEnd) + l = m + 1; + else + return (stbtt_int32)ttUSHORT(classRangeRecord + 4); + } + break; + } + + default: + return -1; // Unsupported definition type, return an error. + } + + // "All glyphs not assigned to a class fall into class 0". (OpenType spec) + return 0; +} + +// Define to STBTT_assert(x) if you want to break on unimplemented formats. +#define STBTT_GPOS_TODO_assert(x) + +static stbtt_int32 stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2) +{ + stbtt_uint16 lookupListOffset; + stbtt_uint8 *lookupList; + stbtt_uint16 lookupCount; + stbtt_uint8 *data; + stbtt_int32 i, sti; + + if (!info->gpos) return 0; + + data = info->data + info->gpos; + + if (ttUSHORT(data+0) != 1) return 0; // Major version 1 + if (ttUSHORT(data+2) != 0) return 0; // Minor version 0 + + lookupListOffset = ttUSHORT(data+8); + lookupList = data + lookupListOffset; + lookupCount = ttUSHORT(lookupList); + + for (i=0; i= pairSetCount) return 0; + + needle=glyph2; + r=pairValueCount-1; + l=0; + + // Binary search. + while (l <= r) { + stbtt_uint16 secondGlyph; + stbtt_uint8 *pairValue; + m = (l + r) >> 1; + pairValue = pairValueArray + (2 + valueRecordPairSizeInBytes) * m; + secondGlyph = ttUSHORT(pairValue); + straw = secondGlyph; + if (needle < straw) + r = m - 1; + else if (needle > straw) + l = m + 1; + else { + stbtt_int16 xAdvance = ttSHORT(pairValue + 2); + return xAdvance; + } + } + } else + return 0; + break; + } + + case 2: { + stbtt_uint16 valueFormat1 = ttUSHORT(table + 4); + stbtt_uint16 valueFormat2 = ttUSHORT(table + 6); + if (valueFormat1 == 4 && valueFormat2 == 0) { // Support more formats? + stbtt_uint16 classDef1Offset = ttUSHORT(table + 8); + stbtt_uint16 classDef2Offset = ttUSHORT(table + 10); + int glyph1class = stbtt__GetGlyphClass(table + classDef1Offset, glyph1); + int glyph2class = stbtt__GetGlyphClass(table + classDef2Offset, glyph2); + + stbtt_uint16 class1Count = ttUSHORT(table + 12); + stbtt_uint16 class2Count = ttUSHORT(table + 14); + stbtt_uint8 *class1Records, *class2Records; + stbtt_int16 xAdvance; + + if (glyph1class < 0 || glyph1class >= class1Count) return 0; // malformed + if (glyph2class < 0 || glyph2class >= class2Count) return 0; // malformed + + class1Records = table + 16; + class2Records = class1Records + 2 * (glyph1class * class2Count); + xAdvance = ttSHORT(class2Records + 2 * glyph2class); + return xAdvance; + } else + return 0; + break; + } + + default: + return 0; // Unsupported position format + } + } + } + + return 0; +} + +STBTT_DEF int stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int g1, int g2) +{ + int xAdvance = 0; + + if (info->gpos) + xAdvance += stbtt__GetGlyphGPOSInfoAdvance(info, g1, g2); + else if (info->kern) + xAdvance += stbtt__GetGlyphKernInfoAdvance(info, g1, g2); + + return xAdvance; +} + +STBTT_DEF int stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2) +{ + if (!info->kern && !info->gpos) // if no kerning table, don't waste time looking up both codepoint->glyphs + return 0; + return stbtt_GetGlyphKernAdvance(info, stbtt_FindGlyphIndex(info,ch1), stbtt_FindGlyphIndex(info,ch2)); +} + +STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing) +{ + stbtt_GetGlyphHMetrics(info, stbtt_FindGlyphIndex(info,codepoint), advanceWidth, leftSideBearing); +} + +STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap) +{ + if (ascent ) *ascent = ttSHORT(info->data+info->hhea + 4); + if (descent) *descent = ttSHORT(info->data+info->hhea + 6); + if (lineGap) *lineGap = ttSHORT(info->data+info->hhea + 8); +} + +STBTT_DEF int stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap) +{ + int tab = stbtt__find_table(info->data, info->fontstart, "OS/2"); + if (!tab) + return 0; + if (typoAscent ) *typoAscent = ttSHORT(info->data+tab + 68); + if (typoDescent) *typoDescent = ttSHORT(info->data+tab + 70); + if (typoLineGap) *typoLineGap = ttSHORT(info->data+tab + 72); + return 1; +} + +STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1) +{ + *x0 = ttSHORT(info->data + info->head + 36); + *y0 = ttSHORT(info->data + info->head + 38); + *x1 = ttSHORT(info->data + info->head + 40); + *y1 = ttSHORT(info->data + info->head + 42); +} + +STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float height) +{ + int fheight = ttSHORT(info->data + info->hhea + 4) - ttSHORT(info->data + info->hhea + 6); + return (float) height / fheight; +} + +STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels) +{ + int unitsPerEm = ttUSHORT(info->data + info->head + 18); + return pixels / unitsPerEm; +} + +STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v) +{ + STBTT_free(v, info->userdata); +} + +STBTT_DEF stbtt_uint8 *stbtt_FindSVGDoc(const stbtt_fontinfo *info, int gl) +{ + int i; + stbtt_uint8 *data = info->data; + stbtt_uint8 *svg_doc_list = data + stbtt__get_svg((stbtt_fontinfo *) info); + + int numEntries = ttUSHORT(svg_doc_list); + stbtt_uint8 *svg_docs = svg_doc_list + 2; + + for(i=0; i= ttUSHORT(svg_doc)) && (gl <= ttUSHORT(svg_doc + 2))) + return svg_doc; + } + return 0; +} + +STBTT_DEF int stbtt_GetGlyphSVG(const stbtt_fontinfo *info, int gl, const char **svg) +{ + stbtt_uint8 *data = info->data; + stbtt_uint8 *svg_doc; + + if (info->svg == 0) + return 0; + + svg_doc = stbtt_FindSVGDoc(info, gl); + if (svg_doc != NULL) { + *svg = (char *) data + info->svg + ttULONG(svg_doc + 4); + return ttULONG(svg_doc + 8); + } else { + return 0; + } +} + +STBTT_DEF int stbtt_GetCodepointSVG(const stbtt_fontinfo *info, int unicode_codepoint, const char **svg) +{ + return stbtt_GetGlyphSVG(info, stbtt_FindGlyphIndex(info, unicode_codepoint), svg); +} + +////////////////////////////////////////////////////////////////////////////// +// +// antialiasing software rasterizer +// + +STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1) +{ + int x0=0,y0=0,x1,y1; // =0 suppresses compiler warning + if (!stbtt_GetGlyphBox(font, glyph, &x0,&y0,&x1,&y1)) { + // e.g. space character + if (ix0) *ix0 = 0; + if (iy0) *iy0 = 0; + if (ix1) *ix1 = 0; + if (iy1) *iy1 = 0; + } else { + // move to integral bboxes (treating pixels as little squares, what pixels get touched)? + if (ix0) *ix0 = STBTT_ifloor( x0 * scale_x + shift_x); + if (iy0) *iy0 = STBTT_ifloor(-y1 * scale_y + shift_y); + if (ix1) *ix1 = STBTT_iceil ( x1 * scale_x + shift_x); + if (iy1) *iy1 = STBTT_iceil (-y0 * scale_y + shift_y); + } +} + +STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1) +{ + stbtt_GetGlyphBitmapBoxSubpixel(font, glyph, scale_x, scale_y,0.0f,0.0f, ix0, iy0, ix1, iy1); +} + +STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1) +{ + stbtt_GetGlyphBitmapBoxSubpixel(font, stbtt_FindGlyphIndex(font,codepoint), scale_x, scale_y,shift_x,shift_y, ix0,iy0,ix1,iy1); +} + +STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1) +{ + stbtt_GetCodepointBitmapBoxSubpixel(font, codepoint, scale_x, scale_y,0.0f,0.0f, ix0,iy0,ix1,iy1); +} + +////////////////////////////////////////////////////////////////////////////// +// +// Rasterizer + +typedef struct stbtt__hheap_chunk +{ + struct stbtt__hheap_chunk *next; +} stbtt__hheap_chunk; + +typedef struct stbtt__hheap +{ + struct stbtt__hheap_chunk *head; + void *first_free; + int num_remaining_in_head_chunk; +} stbtt__hheap; + +static void *stbtt__hheap_alloc(stbtt__hheap *hh, size_t size, void *userdata) +{ + if (hh->first_free) { + void *p = hh->first_free; + hh->first_free = * (void **) p; + return p; + } else { + if (hh->num_remaining_in_head_chunk == 0) { + int count = (size < 32 ? 2000 : size < 128 ? 800 : 100); + stbtt__hheap_chunk *c = (stbtt__hheap_chunk *) STBTT_malloc(sizeof(stbtt__hheap_chunk) + size * count, userdata); + if (c == NULL) + return NULL; + c->next = hh->head; + hh->head = c; + hh->num_remaining_in_head_chunk = count; + } + --hh->num_remaining_in_head_chunk; + return (char *) (hh->head) + sizeof(stbtt__hheap_chunk) + size * hh->num_remaining_in_head_chunk; + } +} + +static void stbtt__hheap_free(stbtt__hheap *hh, void *p) +{ + *(void **) p = hh->first_free; + hh->first_free = p; +} + +static void stbtt__hheap_cleanup(stbtt__hheap *hh, void *userdata) +{ + stbtt__hheap_chunk *c = hh->head; + while (c) { + stbtt__hheap_chunk *n = c->next; + STBTT_free(c, userdata); + c = n; + } +} + +typedef struct stbtt__edge { + float x0,y0, x1,y1; + int invert; +} stbtt__edge; + + +typedef struct stbtt__active_edge +{ + struct stbtt__active_edge *next; + #if STBTT_RASTERIZER_VERSION==1 + int x,dx; + float ey; + int direction; + #elif STBTT_RASTERIZER_VERSION==2 + float fx,fdx,fdy; + float direction; + float sy; + float ey; + #else + #error "Unrecognized value of STBTT_RASTERIZER_VERSION" + #endif +} stbtt__active_edge; + +#if STBTT_RASTERIZER_VERSION == 1 +#define STBTT_FIXSHIFT 10 +#define STBTT_FIX (1 << STBTT_FIXSHIFT) +#define STBTT_FIXMASK (STBTT_FIX-1) + +static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata) +{ + stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata); + float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0); + STBTT_assert(z != NULL); + if (!z) return z; + + // round dx down to avoid overshooting + if (dxdy < 0) + z->dx = -STBTT_ifloor(STBTT_FIX * -dxdy); + else + z->dx = STBTT_ifloor(STBTT_FIX * dxdy); + + z->x = STBTT_ifloor(STBTT_FIX * e->x0 + z->dx * (start_point - e->y0)); // use z->dx so when we offset later it's by the same amount + z->x -= off_x * STBTT_FIX; + + z->ey = e->y1; + z->next = 0; + z->direction = e->invert ? 1 : -1; + return z; +} +#elif STBTT_RASTERIZER_VERSION == 2 +static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata) +{ + stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata); + float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0); + STBTT_assert(z != NULL); + //STBTT_assert(e->y0 <= start_point); + if (!z) return z; + z->fdx = dxdy; + z->fdy = dxdy != 0.0f ? (1.0f/dxdy) : 0.0f; + z->fx = e->x0 + dxdy * (start_point - e->y0); + z->fx -= off_x; + z->direction = e->invert ? 1.0f : -1.0f; + z->sy = e->y0; + z->ey = e->y1; + z->next = 0; + return z; +} +#else +#error "Unrecognized value of STBTT_RASTERIZER_VERSION" +#endif + +#if STBTT_RASTERIZER_VERSION == 1 +// note: this routine clips fills that extend off the edges... ideally this +// wouldn't happen, but it could happen if the truetype glyph bounding boxes +// are wrong, or if the user supplies a too-small bitmap +static void stbtt__fill_active_edges(unsigned char *scanline, int len, stbtt__active_edge *e, int max_weight) +{ + // non-zero winding fill + int x0=0, w=0; + + while (e) { + if (w == 0) { + // if we're currently at zero, we need to record the edge start point + x0 = e->x; w += e->direction; + } else { + int x1 = e->x; w += e->direction; + // if we went to zero, we need to draw + if (w == 0) { + int i = x0 >> STBTT_FIXSHIFT; + int j = x1 >> STBTT_FIXSHIFT; + + if (i < len && j >= 0) { + if (i == j) { + // x0,x1 are the same pixel, so compute combined coverage + scanline[i] = scanline[i] + (stbtt_uint8) ((x1 - x0) * max_weight >> STBTT_FIXSHIFT); + } else { + if (i >= 0) // add antialiasing for x0 + scanline[i] = scanline[i] + (stbtt_uint8) (((STBTT_FIX - (x0 & STBTT_FIXMASK)) * max_weight) >> STBTT_FIXSHIFT); + else + i = -1; // clip + + if (j < len) // add antialiasing for x1 + scanline[j] = scanline[j] + (stbtt_uint8) (((x1 & STBTT_FIXMASK) * max_weight) >> STBTT_FIXSHIFT); + else + j = len; // clip + + for (++i; i < j; ++i) // fill pixels between x0 and x1 + scanline[i] = scanline[i] + (stbtt_uint8) max_weight; + } + } + } + } + + e = e->next; + } +} + +static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata) +{ + stbtt__hheap hh = { 0, 0, 0 }; + stbtt__active_edge *active = NULL; + int y,j=0; + int max_weight = (255 / vsubsample); // weight per vertical scanline + int s; // vertical subsample index + unsigned char scanline_data[512], *scanline; + + if (result->w > 512) + scanline = (unsigned char *) STBTT_malloc(result->w, userdata); + else + scanline = scanline_data; + + y = off_y * vsubsample; + e[n].y0 = (off_y + result->h) * (float) vsubsample + 1; + + while (j < result->h) { + STBTT_memset(scanline, 0, result->w); + for (s=0; s < vsubsample; ++s) { + // find center of pixel for this scanline + float scan_y = y + 0.5f; + stbtt__active_edge **step = &active; + + // update all active edges; + // remove all active edges that terminate before the center of this scanline + while (*step) { + stbtt__active_edge * z = *step; + if (z->ey <= scan_y) { + *step = z->next; // delete from list + STBTT_assert(z->direction); + z->direction = 0; + stbtt__hheap_free(&hh, z); + } else { + z->x += z->dx; // advance to position for current scanline + step = &((*step)->next); // advance through list + } + } + + // resort the list if needed + for(;;) { + int changed=0; + step = &active; + while (*step && (*step)->next) { + if ((*step)->x > (*step)->next->x) { + stbtt__active_edge *t = *step; + stbtt__active_edge *q = t->next; + + t->next = q->next; + q->next = t; + *step = q; + changed = 1; + } + step = &(*step)->next; + } + if (!changed) break; + } + + // insert all edges that start before the center of this scanline -- omit ones that also end on this scanline + while (e->y0 <= scan_y) { + if (e->y1 > scan_y) { + stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y, userdata); + if (z != NULL) { + // find insertion point + if (active == NULL) + active = z; + else if (z->x < active->x) { + // insert at front + z->next = active; + active = z; + } else { + // find thing to insert AFTER + stbtt__active_edge *p = active; + while (p->next && p->next->x < z->x) + p = p->next; + // at this point, p->next->x is NOT < z->x + z->next = p->next; + p->next = z; + } + } + } + ++e; + } + + // now process all active edges in XOR fashion + if (active) + stbtt__fill_active_edges(scanline, result->w, active, max_weight); + + ++y; + } + STBTT_memcpy(result->pixels + j * result->stride, scanline, result->w); + ++j; + } + + stbtt__hheap_cleanup(&hh, userdata); + + if (scanline != scanline_data) + STBTT_free(scanline, userdata); +} + +#elif STBTT_RASTERIZER_VERSION == 2 + +// the edge passed in here does not cross the vertical line at x or the vertical line at x+1 +// (i.e. it has already been clipped to those) +static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edge *e, float x0, float y0, float x1, float y1) +{ + if (y0 == y1) return; + STBTT_assert(y0 < y1); + STBTT_assert(e->sy <= e->ey); + if (y0 > e->ey) return; + if (y1 < e->sy) return; + if (y0 < e->sy) { + x0 += (x1-x0) * (e->sy - y0) / (y1-y0); + y0 = e->sy; + } + if (y1 > e->ey) { + x1 += (x1-x0) * (e->ey - y1) / (y1-y0); + y1 = e->ey; + } + + if (x0 == x) + STBTT_assert(x1 <= x+1); + else if (x0 == x+1) + STBTT_assert(x1 >= x); + else if (x0 <= x) + STBTT_assert(x1 <= x); + else if (x0 >= x+1) + STBTT_assert(x1 >= x+1); + else + STBTT_assert(x1 >= x && x1 <= x+1); + + if (x0 <= x && x1 <= x) + scanline[x] += e->direction * (y1-y0); + else if (x0 >= x+1 && x1 >= x+1) + ; + else { + STBTT_assert(x0 >= x && x0 <= x+1 && x1 >= x && x1 <= x+1); + scanline[x] += e->direction * (y1-y0) * (1-((x0-x)+(x1-x))/2); // coverage = 1 - average x position + } +} + +static float stbtt__sized_trapezoid_area(float height, float top_width, float bottom_width) +{ + STBTT_assert(top_width >= 0); + STBTT_assert(bottom_width >= 0); + return (top_width + bottom_width) / 2.0f * height; +} + +static float stbtt__position_trapezoid_area(float height, float tx0, float tx1, float bx0, float bx1) +{ + return stbtt__sized_trapezoid_area(height, tx1 - tx0, bx1 - bx0); +} + +static float stbtt__sized_triangle_area(float height, float width) +{ + return height * width / 2; +} + +static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top) +{ + float y_bottom = y_top+1; + + while (e) { + // brute force every pixel + + // compute intersection points with top & bottom + STBTT_assert(e->ey >= y_top); + + if (e->fdx == 0) { + float x0 = e->fx; + if (x0 < len) { + if (x0 >= 0) { + stbtt__handle_clipped_edge(scanline,(int) x0,e, x0,y_top, x0,y_bottom); + stbtt__handle_clipped_edge(scanline_fill-1,(int) x0+1,e, x0,y_top, x0,y_bottom); + } else { + stbtt__handle_clipped_edge(scanline_fill-1,0,e, x0,y_top, x0,y_bottom); + } + } + } else { + float x0 = e->fx; + float dx = e->fdx; + float xb = x0 + dx; + float x_top, x_bottom; + float sy0,sy1; + float dy = e->fdy; + STBTT_assert(e->sy <= y_bottom && e->ey >= y_top); + + // compute endpoints of line segment clipped to this scanline (if the + // line segment starts on this scanline. x0 is the intersection of the + // line with y_top, but that may be off the line segment. + if (e->sy > y_top) { + x_top = x0 + dx * (e->sy - y_top); + sy0 = e->sy; + } else { + x_top = x0; + sy0 = y_top; + } + if (e->ey < y_bottom) { + x_bottom = x0 + dx * (e->ey - y_top); + sy1 = e->ey; + } else { + x_bottom = xb; + sy1 = y_bottom; + } + + if (x_top >= 0 && x_bottom >= 0 && x_top < len && x_bottom < len) { + // from here on, we don't have to range check x values + + if ((int) x_top == (int) x_bottom) { + float height; + // simple case, only spans one pixel + int x = (int) x_top; + height = (sy1 - sy0) * e->direction; + STBTT_assert(x >= 0 && x < len); + scanline[x] += stbtt__position_trapezoid_area(height, x_top, x+1.0f, x_bottom, x+1.0f); + scanline_fill[x] += height; // everything right of this pixel is filled + } else { + int x,x1,x2; + float y_crossing, y_final, step, sign, area; + // covers 2+ pixels + if (x_top > x_bottom) { + // flip scanline vertically; signed area is the same + float t; + sy0 = y_bottom - (sy0 - y_top); + sy1 = y_bottom - (sy1 - y_top); + t = sy0, sy0 = sy1, sy1 = t; + t = x_bottom, x_bottom = x_top, x_top = t; + dx = -dx; + dy = -dy; + t = x0, x0 = xb, xb = t; + } + STBTT_assert(dy >= 0); + STBTT_assert(dx >= 0); + + x1 = (int) x_top; + x2 = (int) x_bottom; + // compute intersection with y axis at x1+1 + y_crossing = y_top + dy * (x1+1 - x0); + + // compute intersection with y axis at x2 + y_final = y_top + dy * (x2 - x0); + + // x1 x_top x2 x_bottom + // y_top +------|-----+------------+------------+--------|---+------------+ + // | | | | | | + // | | | | | | + // sy0 | Txxxxx|............|............|............|............| + // y_crossing | *xxxxx.......|............|............|............| + // | | xxxxx..|............|............|............| + // | | /- xx*xxxx........|............|............| + // | | dy < | xxxxxx..|............|............| + // y_final | | \- | xx*xxx.........|............| + // sy1 | | | | xxxxxB...|............| + // | | | | | | + // | | | | | | + // y_bottom +------------+------------+------------+------------+------------+ + // + // goal is to measure the area covered by '.' in each pixel + + // if x2 is right at the right edge of x1, y_crossing can blow up, github #1057 + // @TODO: maybe test against sy1 rather than y_bottom? + if (y_crossing > y_bottom) + y_crossing = y_bottom; + + sign = e->direction; + + // area of the rectangle covered from sy0..y_crossing + area = sign * (y_crossing-sy0); + + // area of the triangle (x_top,sy0), (x1+1,sy0), (x1+1,y_crossing) + scanline[x1] += stbtt__sized_triangle_area(area, x1+1 - x_top); + + // check if final y_crossing is blown up; no test case for this + if (y_final > y_bottom) { + y_final = y_bottom; + dy = (y_final - y_crossing ) / (x2 - (x1+1)); // if denom=0, y_final = y_crossing, so y_final <= y_bottom + } + + // in second pixel, area covered by line segment found in first pixel + // is always a rectangle 1 wide * the height of that line segment; this + // is exactly what the variable 'area' stores. it also gets a contribution + // from the line segment within it. the THIRD pixel will get the first + // pixel's rectangle contribution, the second pixel's rectangle contribution, + // and its own contribution. the 'own contribution' is the same in every pixel except + // the leftmost and rightmost, a trapezoid that slides down in each pixel. + // the second pixel's contribution to the third pixel will be the + // rectangle 1 wide times the height change in the second pixel, which is dy. + + step = sign * dy * 1; // dy is dy/dx, change in y for every 1 change in x, + // which multiplied by 1-pixel-width is how much pixel area changes for each step in x + // so the area advances by 'step' every time + + for (x = x1+1; x < x2; ++x) { + scanline[x] += area + step/2; // area of trapezoid is 1*step/2 + area += step; + } + STBTT_assert(STBTT_fabs(area) <= 1.01f); // accumulated error from area += step unless we round step down + STBTT_assert(sy1 > y_final-0.01f); + + // area covered in the last pixel is the rectangle from all the pixels to the left, + // plus the trapezoid filled by the line segment in this pixel all the way to the right edge + scanline[x2] += area + sign * stbtt__position_trapezoid_area(sy1-y_final, (float) x2, x2+1.0f, x_bottom, x2+1.0f); + + // the rest of the line is filled based on the total height of the line segment in this pixel + scanline_fill[x2] += sign * (sy1-sy0); + } + } else { + // if edge goes outside of box we're drawing, we require + // clipping logic. since this does not match the intended use + // of this library, we use a different, very slow brute + // force implementation + // note though that this does happen some of the time because + // x_top and x_bottom can be extrapolated at the top & bottom of + // the shape and actually lie outside the bounding box + int x; + for (x=0; x < len; ++x) { + // cases: + // + // there can be up to two intersections with the pixel. any intersection + // with left or right edges can be handled by splitting into two (or three) + // regions. intersections with top & bottom do not necessitate case-wise logic. + // + // the old way of doing this found the intersections with the left & right edges, + // then used some simple logic to produce up to three segments in sorted order + // from top-to-bottom. however, this had a problem: if an x edge was epsilon + // across the x border, then the corresponding y position might not be distinct + // from the other y segment, and it might ignored as an empty segment. to avoid + // that, we need to explicitly produce segments based on x positions. + + // rename variables to clearly-defined pairs + float y0 = y_top; + float x1 = (float) (x); + float x2 = (float) (x+1); + float x3 = xb; + float y3 = y_bottom; + + // x = e->x + e->dx * (y-y_top) + // (y-y_top) = (x - e->x) / e->dx + // y = (x - e->x) / e->dx + y_top + float y1 = (x - x0) / dx + y_top; + float y2 = (x+1 - x0) / dx + y_top; + + if (x0 < x1 && x3 > x2) { // three segments descending down-right + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1); + stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x2,y2); + stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3); + } else if (x3 < x1 && x0 > x2) { // three segments descending down-left + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2); + stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x1,y1); + stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3); + } else if (x0 < x1 && x3 > x1) { // two segments across x, down-right + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1); + stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3); + } else if (x3 < x1 && x0 > x1) { // two segments across x, down-left + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1); + stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3); + } else if (x0 < x2 && x3 > x2) { // two segments across x+1, down-right + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2); + stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3); + } else if (x3 < x2 && x0 > x2) { // two segments across x+1, down-left + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2); + stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3); + } else { // one segment + stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x3,y3); + } + } + } + } + e = e->next; + } +} + +// directly AA rasterize edges w/o supersampling +static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata) +{ + stbtt__hheap hh = { 0, 0, 0 }; + stbtt__active_edge *active = NULL; + int y,j=0, i; + float scanline_data[129], *scanline, *scanline2; + + STBTT__NOTUSED(vsubsample); + + if (result->w > 64) + scanline = (float *) STBTT_malloc((result->w*2+1) * sizeof(float), userdata); + else + scanline = scanline_data; + + scanline2 = scanline + result->w; + + y = off_y; + e[n].y0 = (float) (off_y + result->h) + 1; + + while (j < result->h) { + // find center of pixel for this scanline + float scan_y_top = y + 0.0f; + float scan_y_bottom = y + 1.0f; + stbtt__active_edge **step = &active; + + STBTT_memset(scanline , 0, result->w*sizeof(scanline[0])); + STBTT_memset(scanline2, 0, (result->w+1)*sizeof(scanline[0])); + + // update all active edges; + // remove all active edges that terminate before the top of this scanline + while (*step) { + stbtt__active_edge * z = *step; + if (z->ey <= scan_y_top) { + *step = z->next; // delete from list + STBTT_assert(z->direction); + z->direction = 0; + stbtt__hheap_free(&hh, z); + } else { + step = &((*step)->next); // advance through list + } + } + + // insert all edges that start before the bottom of this scanline + while (e->y0 <= scan_y_bottom) { + if (e->y0 != e->y1) { + stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y_top, userdata); + if (z != NULL) { + if (j == 0 && off_y != 0) { + if (z->ey < scan_y_top) { + // this can happen due to subpixel positioning and some kind of fp rounding error i think + z->ey = scan_y_top; + } + } + STBTT_assert(z->ey >= scan_y_top); // if we get really unlucky a tiny bit of an edge can be out of bounds + // insert at front + z->next = active; + active = z; + } + } + ++e; + } + + // now process all active edges + if (active) + stbtt__fill_active_edges_new(scanline, scanline2+1, result->w, active, scan_y_top); + + { + float sum = 0; + for (i=0; i < result->w; ++i) { + float k; + int m; + sum += scanline2[i]; + k = scanline[i] + sum; + k = (float) STBTT_fabs(k)*255 + 0.5f; + m = (int) k; + if (m > 255) m = 255; + result->pixels[j*result->stride + i] = (unsigned char) m; + } + } + // advance all the edges + step = &active; + while (*step) { + stbtt__active_edge *z = *step; + z->fx += z->fdx; // advance to position for current scanline + step = &((*step)->next); // advance through list + } + + ++y; + ++j; + } + + stbtt__hheap_cleanup(&hh, userdata); + + if (scanline != scanline_data) + STBTT_free(scanline, userdata); +} +#else +#error "Unrecognized value of STBTT_RASTERIZER_VERSION" +#endif + +#define STBTT__COMPARE(a,b) ((a)->y0 < (b)->y0) + +static void stbtt__sort_edges_ins_sort(stbtt__edge *p, int n) +{ + int i,j; + for (i=1; i < n; ++i) { + stbtt__edge t = p[i], *a = &t; + j = i; + while (j > 0) { + stbtt__edge *b = &p[j-1]; + int c = STBTT__COMPARE(a,b); + if (!c) break; + p[j] = p[j-1]; + --j; + } + if (i != j) + p[j] = t; + } +} + +static void stbtt__sort_edges_quicksort(stbtt__edge *p, int n) +{ + /* threshold for transitioning to insertion sort */ + while (n > 12) { + stbtt__edge t; + int c01,c12,c,m,i,j; + + /* compute median of three */ + m = n >> 1; + c01 = STBTT__COMPARE(&p[0],&p[m]); + c12 = STBTT__COMPARE(&p[m],&p[n-1]); + /* if 0 >= mid >= end, or 0 < mid < end, then use mid */ + if (c01 != c12) { + /* otherwise, we'll need to swap something else to middle */ + int z; + c = STBTT__COMPARE(&p[0],&p[n-1]); + /* 0>mid && midn => n; 0 0 */ + /* 0n: 0>n => 0; 0 n */ + z = (c == c12) ? 0 : n-1; + t = p[z]; + p[z] = p[m]; + p[m] = t; + } + /* now p[m] is the median-of-three */ + /* swap it to the beginning so it won't move around */ + t = p[0]; + p[0] = p[m]; + p[m] = t; + + /* partition loop */ + i=1; + j=n-1; + for(;;) { + /* handling of equality is crucial here */ + /* for sentinels & efficiency with duplicates */ + for (;;++i) { + if (!STBTT__COMPARE(&p[i], &p[0])) break; + } + for (;;--j) { + if (!STBTT__COMPARE(&p[0], &p[j])) break; + } + /* make sure we haven't crossed */ + if (i >= j) break; + t = p[i]; + p[i] = p[j]; + p[j] = t; + + ++i; + --j; + } + /* recurse on smaller side, iterate on larger */ + if (j < (n-i)) { + stbtt__sort_edges_quicksort(p,j); + p = p+i; + n = n-i; + } else { + stbtt__sort_edges_quicksort(p+i, n-i); + n = j; + } + } +} + +static void stbtt__sort_edges(stbtt__edge *p, int n) +{ + stbtt__sort_edges_quicksort(p, n); + stbtt__sort_edges_ins_sort(p, n); +} + +typedef struct +{ + float x,y; +} stbtt__point; + +static void stbtt__rasterize(stbtt__bitmap *result, stbtt__point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata) +{ + float y_scale_inv = invert ? -scale_y : scale_y; + stbtt__edge *e; + int n,i,j,k,m; +#if STBTT_RASTERIZER_VERSION == 1 + int vsubsample = result->h < 8 ? 15 : 5; +#elif STBTT_RASTERIZER_VERSION == 2 + int vsubsample = 1; +#else + #error "Unrecognized value of STBTT_RASTERIZER_VERSION" +#endif + // vsubsample should divide 255 evenly; otherwise we won't reach full opacity + + // now we have to blow out the windings into explicit edge lists + n = 0; + for (i=0; i < windings; ++i) + n += wcount[i]; + + e = (stbtt__edge *) STBTT_malloc(sizeof(*e) * (n+1), userdata); // add an extra one as a sentinel + if (e == 0) return; + n = 0; + + m=0; + for (i=0; i < windings; ++i) { + stbtt__point *p = pts + m; + m += wcount[i]; + j = wcount[i]-1; + for (k=0; k < wcount[i]; j=k++) { + int a=k,b=j; + // skip the edge if horizontal + if (p[j].y == p[k].y) + continue; + // add edge from j to k to the list + e[n].invert = 0; + if (invert ? p[j].y > p[k].y : p[j].y < p[k].y) { + e[n].invert = 1; + a=j,b=k; + } + e[n].x0 = p[a].x * scale_x + shift_x; + e[n].y0 = (p[a].y * y_scale_inv + shift_y) * vsubsample; + e[n].x1 = p[b].x * scale_x + shift_x; + e[n].y1 = (p[b].y * y_scale_inv + shift_y) * vsubsample; + ++n; + } + } + + // now sort the edges by their highest point (should snap to integer, and then by x) + //STBTT_sort(e, n, sizeof(e[0]), stbtt__edge_compare); + stbtt__sort_edges(e, n); + + // now, traverse the scanlines and find the intersections on each scanline, use xor winding rule + stbtt__rasterize_sorted_edges(result, e, n, vsubsample, off_x, off_y, userdata); + + STBTT_free(e, userdata); +} + +static void stbtt__add_point(stbtt__point *points, int n, float x, float y) +{ + if (!points) return; // during first pass, it's unallocated + points[n].x = x; + points[n].y = y; +} + +// tessellate until threshold p is happy... @TODO warped to compensate for non-linear stretching +static int stbtt__tesselate_curve(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float objspace_flatness_squared, int n) +{ + // midpoint + float mx = (x0 + 2*x1 + x2)/4; + float my = (y0 + 2*y1 + y2)/4; + // versus directly drawn line + float dx = (x0+x2)/2 - mx; + float dy = (y0+y2)/2 - my; + if (n > 16) // 65536 segments on one curve better be enough! + return 1; + if (dx*dx+dy*dy > objspace_flatness_squared) { // half-pixel error allowed... need to be smaller if AA + stbtt__tesselate_curve(points, num_points, x0,y0, (x0+x1)/2.0f,(y0+y1)/2.0f, mx,my, objspace_flatness_squared,n+1); + stbtt__tesselate_curve(points, num_points, mx,my, (x1+x2)/2.0f,(y1+y2)/2.0f, x2,y2, objspace_flatness_squared,n+1); + } else { + stbtt__add_point(points, *num_points,x2,y2); + *num_points = *num_points+1; + } + return 1; +} + +static void stbtt__tesselate_cubic(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float x3, float y3, float objspace_flatness_squared, int n) +{ + // @TODO this "flatness" calculation is just made-up nonsense that seems to work well enough + float dx0 = x1-x0; + float dy0 = y1-y0; + float dx1 = x2-x1; + float dy1 = y2-y1; + float dx2 = x3-x2; + float dy2 = y3-y2; + float dx = x3-x0; + float dy = y3-y0; + float longlen = (float) (STBTT_sqrt(dx0*dx0+dy0*dy0)+STBTT_sqrt(dx1*dx1+dy1*dy1)+STBTT_sqrt(dx2*dx2+dy2*dy2)); + float shortlen = (float) STBTT_sqrt(dx*dx+dy*dy); + float flatness_squared = longlen*longlen-shortlen*shortlen; + + if (n > 16) // 65536 segments on one curve better be enough! + return; + + if (flatness_squared > objspace_flatness_squared) { + float x01 = (x0+x1)/2; + float y01 = (y0+y1)/2; + float x12 = (x1+x2)/2; + float y12 = (y1+y2)/2; + float x23 = (x2+x3)/2; + float y23 = (y2+y3)/2; + + float xa = (x01+x12)/2; + float ya = (y01+y12)/2; + float xb = (x12+x23)/2; + float yb = (y12+y23)/2; + + float mx = (xa+xb)/2; + float my = (ya+yb)/2; + + stbtt__tesselate_cubic(points, num_points, x0,y0, x01,y01, xa,ya, mx,my, objspace_flatness_squared,n+1); + stbtt__tesselate_cubic(points, num_points, mx,my, xb,yb, x23,y23, x3,y3, objspace_flatness_squared,n+1); + } else { + stbtt__add_point(points, *num_points,x3,y3); + *num_points = *num_points+1; + } +} + +// returns number of contours +static stbtt__point *stbtt_FlattenCurves(stbtt_vertex *vertices, int num_verts, float objspace_flatness, int **contour_lengths, int *num_contours, void *userdata) +{ + stbtt__point *points=0; + int num_points=0; + + float objspace_flatness_squared = objspace_flatness * objspace_flatness; + int i,n=0,start=0, pass; + + // count how many "moves" there are to get the contour count + for (i=0; i < num_verts; ++i) + if (vertices[i].type == STBTT_vmove) + ++n; + + *num_contours = n; + if (n == 0) return 0; + + *contour_lengths = (int *) STBTT_malloc(sizeof(**contour_lengths) * n, userdata); + + if (*contour_lengths == 0) { + *num_contours = 0; + return 0; + } + + // make two passes through the points so we don't need to realloc + for (pass=0; pass < 2; ++pass) { + float x=0,y=0; + if (pass == 1) { + points = (stbtt__point *) STBTT_malloc(num_points * sizeof(points[0]), userdata); + if (points == NULL) goto error; + } + num_points = 0; + n= -1; + for (i=0; i < num_verts; ++i) { + switch (vertices[i].type) { + case STBTT_vmove: + // start the next contour + if (n >= 0) + (*contour_lengths)[n] = num_points - start; + ++n; + start = num_points; + + x = vertices[i].x, y = vertices[i].y; + stbtt__add_point(points, num_points++, x,y); + break; + case STBTT_vline: + x = vertices[i].x, y = vertices[i].y; + stbtt__add_point(points, num_points++, x, y); + break; + case STBTT_vcurve: + stbtt__tesselate_curve(points, &num_points, x,y, + vertices[i].cx, vertices[i].cy, + vertices[i].x, vertices[i].y, + objspace_flatness_squared, 0); + x = vertices[i].x, y = vertices[i].y; + break; + case STBTT_vcubic: + stbtt__tesselate_cubic(points, &num_points, x,y, + vertices[i].cx, vertices[i].cy, + vertices[i].cx1, vertices[i].cy1, + vertices[i].x, vertices[i].y, + objspace_flatness_squared, 0); + x = vertices[i].x, y = vertices[i].y; + break; + } + } + (*contour_lengths)[n] = num_points - start; + } + + return points; +error: + STBTT_free(points, userdata); + STBTT_free(*contour_lengths, userdata); + *contour_lengths = 0; + *num_contours = 0; + return NULL; +} + +STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata) +{ + float scale = scale_x > scale_y ? scale_y : scale_x; + int winding_count = 0; + int *winding_lengths = NULL; + stbtt__point *windings = stbtt_FlattenCurves(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata); + if (windings) { + stbtt__rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata); + STBTT_free(winding_lengths, userdata); + STBTT_free(windings, userdata); + } +} + +STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata) +{ + STBTT_free(bitmap, userdata); +} + +STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff) +{ + int ix0,iy0,ix1,iy1; + stbtt__bitmap gbm; + stbtt_vertex *vertices; + int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices); + + if (scale_x == 0) scale_x = scale_y; + if (scale_y == 0) { + if (scale_x == 0) { + STBTT_free(vertices, info->userdata); + return NULL; + } + scale_y = scale_x; + } + + stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,&ix1,&iy1); + + // now we get the size + gbm.w = (ix1 - ix0); + gbm.h = (iy1 - iy0); + gbm.pixels = NULL; // in case we error + + if (width ) *width = gbm.w; + if (height) *height = gbm.h; + if (xoff ) *xoff = ix0; + if (yoff ) *yoff = iy0; + + if (gbm.w && gbm.h) { + gbm.pixels = (unsigned char *) STBTT_malloc(gbm.w * gbm.h, info->userdata); + if (gbm.pixels) { + gbm.stride = gbm.w; + + stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata); + } + } + STBTT_free(vertices, info->userdata); + return gbm.pixels; +} + +STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff) +{ + return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, glyph, width, height, xoff, yoff); +} + +STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph) +{ + int ix0,iy0; + stbtt_vertex *vertices; + int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices); + stbtt__bitmap gbm; + + stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,0,0); + gbm.pixels = output; + gbm.w = out_w; + gbm.h = out_h; + gbm.stride = out_stride; + + if (gbm.w && gbm.h) + stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata); + + STBTT_free(vertices, info->userdata); +} + +STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph) +{ + stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, glyph); +} + +STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff) +{ + return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y,shift_x,shift_y, stbtt_FindGlyphIndex(info,codepoint), width,height,xoff,yoff); +} + +STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint) +{ + stbtt_MakeGlyphBitmapSubpixelPrefilter(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, oversample_x, oversample_y, sub_x, sub_y, stbtt_FindGlyphIndex(info,codepoint)); +} + +STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint) +{ + stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info,codepoint)); +} + +STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff) +{ + return stbtt_GetCodepointBitmapSubpixel(info, scale_x, scale_y, 0.0f,0.0f, codepoint, width,height,xoff,yoff); +} + +STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint) +{ + stbtt_MakeCodepointBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, codepoint); +} + +////////////////////////////////////////////////////////////////////////////// +// +// bitmap baking +// +// This is SUPER-CRAPPY packing to keep source code small + +static int stbtt_BakeFontBitmap_internal(unsigned char *data, int offset, // font location (use offset=0 for plain .ttf) + float pixel_height, // height of font in pixels + unsigned char *pixels, int pw, int ph, // bitmap to be filled in + int first_char, int num_chars, // characters to bake + stbtt_bakedchar *chardata) +{ + float scale; + int x,y,bottom_y, i; + stbtt_fontinfo f; + f.userdata = NULL; + if (!stbtt_InitFont(&f, data, offset)) + return -1; + STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels + x=y=1; + bottom_y = 1; + + scale = stbtt_ScaleForPixelHeight(&f, pixel_height); + + for (i=0; i < num_chars; ++i) { + int advance, lsb, x0,y0,x1,y1,gw,gh; + int g = stbtt_FindGlyphIndex(&f, first_char + i); + stbtt_GetGlyphHMetrics(&f, g, &advance, &lsb); + stbtt_GetGlyphBitmapBox(&f, g, scale,scale, &x0,&y0,&x1,&y1); + gw = x1-x0; + gh = y1-y0; + if (x + gw + 1 >= pw) + y = bottom_y, x = 1; // advance to next row + if (y + gh + 1 >= ph) // check if it fits vertically AFTER potentially moving to next row + return -i; + STBTT_assert(x+gw < pw); + STBTT_assert(y+gh < ph); + stbtt_MakeGlyphBitmap(&f, pixels+x+y*pw, gw,gh,pw, scale,scale, g); + chardata[i].x0 = (stbtt_int16) x; + chardata[i].y0 = (stbtt_int16) y; + chardata[i].x1 = (stbtt_int16) (x + gw); + chardata[i].y1 = (stbtt_int16) (y + gh); + chardata[i].xadvance = scale * advance; + chardata[i].xoff = (float) x0; + chardata[i].yoff = (float) y0; + x = x + gw + 1; + if (y+gh+1 > bottom_y) + bottom_y = y+gh+1; + } + return bottom_y; +} + +STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int opengl_fillrule) +{ + float d3d_bias = opengl_fillrule ? 0 : -0.5f; + float ipw = 1.0f / pw, iph = 1.0f / ph; + const stbtt_bakedchar *b = chardata + char_index; + int round_x = STBTT_ifloor((*xpos + b->xoff) + 0.5f); + int round_y = STBTT_ifloor((*ypos + b->yoff) + 0.5f); + + q->x0 = round_x + d3d_bias; + q->y0 = round_y + d3d_bias; + q->x1 = round_x + b->x1 - b->x0 + d3d_bias; + q->y1 = round_y + b->y1 - b->y0 + d3d_bias; + + q->s0 = b->x0 * ipw; + q->t0 = b->y0 * iph; + q->s1 = b->x1 * ipw; + q->t1 = b->y1 * iph; + + *xpos += b->xadvance; +} + +////////////////////////////////////////////////////////////////////////////// +// +// rectangle packing replacement routines if you don't have stb_rect_pack.h +// + +#ifndef STB_RECT_PACK_VERSION + +typedef int stbrp_coord; + +//////////////////////////////////////////////////////////////////////////////////// +// // +// // +// COMPILER WARNING ?!?!? // +// // +// // +// if you get a compile warning due to these symbols being defined more than // +// once, move #include "stb_rect_pack.h" before #include "stb_truetype.h" // +// // +//////////////////////////////////////////////////////////////////////////////////// + +typedef struct +{ + int width,height; + int x,y,bottom_y; +} stbrp_context; + +typedef struct +{ + unsigned char x; +} stbrp_node; + +struct stbrp_rect +{ + stbrp_coord x,y; + int id,w,h,was_packed; +}; + +static void stbrp_init_target(stbrp_context *con, int pw, int ph, stbrp_node *nodes, int num_nodes) +{ + con->width = pw; + con->height = ph; + con->x = 0; + con->y = 0; + con->bottom_y = 0; + STBTT__NOTUSED(nodes); + STBTT__NOTUSED(num_nodes); +} + +static void stbrp_pack_rects(stbrp_context *con, stbrp_rect *rects, int num_rects) +{ + int i; + for (i=0; i < num_rects; ++i) { + if (con->x + rects[i].w > con->width) { + con->x = 0; + con->y = con->bottom_y; + } + if (con->y + rects[i].h > con->height) + break; + rects[i].x = con->x; + rects[i].y = con->y; + rects[i].was_packed = 1; + con->x += rects[i].w; + if (con->y + rects[i].h > con->bottom_y) + con->bottom_y = con->y + rects[i].h; + } + for ( ; i < num_rects; ++i) + rects[i].was_packed = 0; +} +#endif + +////////////////////////////////////////////////////////////////////////////// +// +// bitmap baking +// +// This is SUPER-AWESOME (tm Ryan Gordon) packing using stb_rect_pack.h. If +// stb_rect_pack.h isn't available, it uses the BakeFontBitmap strategy. + +STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int pw, int ph, int stride_in_bytes, int padding, void *alloc_context) +{ + stbrp_context *context = (stbrp_context *) STBTT_malloc(sizeof(*context) ,alloc_context); + int num_nodes = pw - padding; + stbrp_node *nodes = (stbrp_node *) STBTT_malloc(sizeof(*nodes ) * num_nodes,alloc_context); + + if (context == NULL || nodes == NULL) { + if (context != NULL) STBTT_free(context, alloc_context); + if (nodes != NULL) STBTT_free(nodes , alloc_context); + return 0; + } + + spc->user_allocator_context = alloc_context; + spc->width = pw; + spc->height = ph; + spc->pixels = pixels; + spc->pack_info = context; + spc->nodes = nodes; + spc->padding = padding; + spc->stride_in_bytes = stride_in_bytes != 0 ? stride_in_bytes : pw; + spc->h_oversample = 1; + spc->v_oversample = 1; + spc->skip_missing = 0; + + stbrp_init_target(context, pw-padding, ph-padding, nodes, num_nodes); + + if (pixels) + STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels + + return 1; +} + +STBTT_DEF void stbtt_PackEnd (stbtt_pack_context *spc) +{ + STBTT_free(spc->nodes , spc->user_allocator_context); + STBTT_free(spc->pack_info, spc->user_allocator_context); +} + +STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample) +{ + STBTT_assert(h_oversample <= STBTT_MAX_OVERSAMPLE); + STBTT_assert(v_oversample <= STBTT_MAX_OVERSAMPLE); + if (h_oversample <= STBTT_MAX_OVERSAMPLE) + spc->h_oversample = h_oversample; + if (v_oversample <= STBTT_MAX_OVERSAMPLE) + spc->v_oversample = v_oversample; +} + +STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip) +{ + spc->skip_missing = skip; +} + +#define STBTT__OVER_MASK (STBTT_MAX_OVERSAMPLE-1) + +static void stbtt__h_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width) +{ + unsigned char buffer[STBTT_MAX_OVERSAMPLE]; + int safe_w = w - kernel_width; + int j; + STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze + for (j=0; j < h; ++j) { + int i; + unsigned int total; + STBTT_memset(buffer, 0, kernel_width); + + total = 0; + + // make kernel_width a constant in common cases so compiler can optimize out the divide + switch (kernel_width) { + case 2: + for (i=0; i <= safe_w; ++i) { + total += pixels[i] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i]; + pixels[i] = (unsigned char) (total / 2); + } + break; + case 3: + for (i=0; i <= safe_w; ++i) { + total += pixels[i] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i]; + pixels[i] = (unsigned char) (total / 3); + } + break; + case 4: + for (i=0; i <= safe_w; ++i) { + total += pixels[i] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i]; + pixels[i] = (unsigned char) (total / 4); + } + break; + case 5: + for (i=0; i <= safe_w; ++i) { + total += pixels[i] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i]; + pixels[i] = (unsigned char) (total / 5); + } + break; + default: + for (i=0; i <= safe_w; ++i) { + total += pixels[i] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i]; + pixels[i] = (unsigned char) (total / kernel_width); + } + break; + } + + for (; i < w; ++i) { + STBTT_assert(pixels[i] == 0); + total -= buffer[i & STBTT__OVER_MASK]; + pixels[i] = (unsigned char) (total / kernel_width); + } + + pixels += stride_in_bytes; + } +} + +static void stbtt__v_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width) +{ + unsigned char buffer[STBTT_MAX_OVERSAMPLE]; + int safe_h = h - kernel_width; + int j; + STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze + for (j=0; j < w; ++j) { + int i; + unsigned int total; + STBTT_memset(buffer, 0, kernel_width); + + total = 0; + + // make kernel_width a constant in common cases so compiler can optimize out the divide + switch (kernel_width) { + case 2: + for (i=0; i <= safe_h; ++i) { + total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes]; + pixels[i*stride_in_bytes] = (unsigned char) (total / 2); + } + break; + case 3: + for (i=0; i <= safe_h; ++i) { + total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes]; + pixels[i*stride_in_bytes] = (unsigned char) (total / 3); + } + break; + case 4: + for (i=0; i <= safe_h; ++i) { + total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes]; + pixels[i*stride_in_bytes] = (unsigned char) (total / 4); + } + break; + case 5: + for (i=0; i <= safe_h; ++i) { + total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes]; + pixels[i*stride_in_bytes] = (unsigned char) (total / 5); + } + break; + default: + for (i=0; i <= safe_h; ++i) { + total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK]; + buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes]; + pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width); + } + break; + } + + for (; i < h; ++i) { + STBTT_assert(pixels[i*stride_in_bytes] == 0); + total -= buffer[i & STBTT__OVER_MASK]; + pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width); + } + + pixels += 1; + } +} + +static float stbtt__oversample_shift(int oversample) +{ + if (!oversample) + return 0.0f; + + // The prefilter is a box filter of width "oversample", + // which shifts phase by (oversample - 1)/2 pixels in + // oversampled space. We want to shift in the opposite + // direction to counter this. + return (float)-(oversample - 1) / (2.0f * (float)oversample); +} + +// rects array must be big enough to accommodate all characters in the given ranges +STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects) +{ + int i,j,k; + int missing_glyph_added = 0; + + k=0; + for (i=0; i < num_ranges; ++i) { + float fh = ranges[i].font_size; + float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh); + ranges[i].h_oversample = (unsigned char) spc->h_oversample; + ranges[i].v_oversample = (unsigned char) spc->v_oversample; + for (j=0; j < ranges[i].num_chars; ++j) { + int x0,y0,x1,y1; + int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j]; + int glyph = stbtt_FindGlyphIndex(info, codepoint); + if (glyph == 0 && (spc->skip_missing || missing_glyph_added)) { + rects[k].w = rects[k].h = 0; + } else { + stbtt_GetGlyphBitmapBoxSubpixel(info,glyph, + scale * spc->h_oversample, + scale * spc->v_oversample, + 0,0, + &x0,&y0,&x1,&y1); + rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1); + rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1); + if (glyph == 0) + missing_glyph_added = 1; + } + ++k; + } + } + + return k; +} + +STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int prefilter_x, int prefilter_y, float *sub_x, float *sub_y, int glyph) +{ + stbtt_MakeGlyphBitmapSubpixel(info, + output, + out_w - (prefilter_x - 1), + out_h - (prefilter_y - 1), + out_stride, + scale_x, + scale_y, + shift_x, + shift_y, + glyph); + + if (prefilter_x > 1) + stbtt__h_prefilter(output, out_w, out_h, out_stride, prefilter_x); + + if (prefilter_y > 1) + stbtt__v_prefilter(output, out_w, out_h, out_stride, prefilter_y); + + *sub_x = stbtt__oversample_shift(prefilter_x); + *sub_y = stbtt__oversample_shift(prefilter_y); +} + +// rects array must be big enough to accommodate all characters in the given ranges +STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects) +{ + int i,j,k, missing_glyph = -1, return_value = 1; + + // save current values + int old_h_over = spc->h_oversample; + int old_v_over = spc->v_oversample; + + k = 0; + for (i=0; i < num_ranges; ++i) { + float fh = ranges[i].font_size; + float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh); + float recip_h,recip_v,sub_x,sub_y; + spc->h_oversample = ranges[i].h_oversample; + spc->v_oversample = ranges[i].v_oversample; + recip_h = 1.0f / spc->h_oversample; + recip_v = 1.0f / spc->v_oversample; + sub_x = stbtt__oversample_shift(spc->h_oversample); + sub_y = stbtt__oversample_shift(spc->v_oversample); + for (j=0; j < ranges[i].num_chars; ++j) { + stbrp_rect *r = &rects[k]; + if (r->was_packed && r->w != 0 && r->h != 0) { + stbtt_packedchar *bc = &ranges[i].chardata_for_range[j]; + int advance, lsb, x0,y0,x1,y1; + int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j]; + int glyph = stbtt_FindGlyphIndex(info, codepoint); + stbrp_coord pad = (stbrp_coord) spc->padding; + + // pad on left and top + r->x += pad; + r->y += pad; + r->w -= pad; + r->h -= pad; + stbtt_GetGlyphHMetrics(info, glyph, &advance, &lsb); + stbtt_GetGlyphBitmapBox(info, glyph, + scale * spc->h_oversample, + scale * spc->v_oversample, + &x0,&y0,&x1,&y1); + stbtt_MakeGlyphBitmapSubpixel(info, + spc->pixels + r->x + r->y*spc->stride_in_bytes, + r->w - spc->h_oversample+1, + r->h - spc->v_oversample+1, + spc->stride_in_bytes, + scale * spc->h_oversample, + scale * spc->v_oversample, + 0,0, + glyph); + + if (spc->h_oversample > 1) + stbtt__h_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes, + r->w, r->h, spc->stride_in_bytes, + spc->h_oversample); + + if (spc->v_oversample > 1) + stbtt__v_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes, + r->w, r->h, spc->stride_in_bytes, + spc->v_oversample); + + bc->x0 = (stbtt_int16) r->x; + bc->y0 = (stbtt_int16) r->y; + bc->x1 = (stbtt_int16) (r->x + r->w); + bc->y1 = (stbtt_int16) (r->y + r->h); + bc->xadvance = scale * advance; + bc->xoff = (float) x0 * recip_h + sub_x; + bc->yoff = (float) y0 * recip_v + sub_y; + bc->xoff2 = (x0 + r->w) * recip_h + sub_x; + bc->yoff2 = (y0 + r->h) * recip_v + sub_y; + + if (glyph == 0) + missing_glyph = j; + } else if (spc->skip_missing) { + return_value = 0; + } else if (r->was_packed && r->w == 0 && r->h == 0 && missing_glyph >= 0) { + ranges[i].chardata_for_range[j] = ranges[i].chardata_for_range[missing_glyph]; + } else { + return_value = 0; // if any fail, report failure + } + + ++k; + } + } + + // restore original values + spc->h_oversample = old_h_over; + spc->v_oversample = old_v_over; + + return return_value; +} + +STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects) +{ + stbrp_pack_rects((stbrp_context *) spc->pack_info, rects, num_rects); +} + +STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges) +{ + stbtt_fontinfo info; + int i,j,n, return_value = 1; + //stbrp_context *context = (stbrp_context *) spc->pack_info; + stbrp_rect *rects; + + // flag all characters as NOT packed + for (i=0; i < num_ranges; ++i) + for (j=0; j < ranges[i].num_chars; ++j) + ranges[i].chardata_for_range[j].x0 = + ranges[i].chardata_for_range[j].y0 = + ranges[i].chardata_for_range[j].x1 = + ranges[i].chardata_for_range[j].y1 = 0; + + n = 0; + for (i=0; i < num_ranges; ++i) + n += ranges[i].num_chars; + + rects = (stbrp_rect *) STBTT_malloc(sizeof(*rects) * n, spc->user_allocator_context); + if (rects == NULL) + return 0; + + info.userdata = spc->user_allocator_context; + stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata,font_index)); + + n = stbtt_PackFontRangesGatherRects(spc, &info, ranges, num_ranges, rects); + + stbtt_PackFontRangesPackRects(spc, rects, n); + + return_value = stbtt_PackFontRangesRenderIntoRects(spc, &info, ranges, num_ranges, rects); + + STBTT_free(rects, spc->user_allocator_context); + return return_value; +} + +STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size, + int first_unicode_codepoint_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range) +{ + stbtt_pack_range range; + range.first_unicode_codepoint_in_range = first_unicode_codepoint_in_range; + range.array_of_unicode_codepoints = NULL; + range.num_chars = num_chars_in_range; + range.chardata_for_range = chardata_for_range; + range.font_size = font_size; + return stbtt_PackFontRanges(spc, fontdata, font_index, &range, 1); +} + +STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap) +{ + int i_ascent, i_descent, i_lineGap; + float scale; + stbtt_fontinfo info; + stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata, index)); + scale = size > 0 ? stbtt_ScaleForPixelHeight(&info, size) : stbtt_ScaleForMappingEmToPixels(&info, -size); + stbtt_GetFontVMetrics(&info, &i_ascent, &i_descent, &i_lineGap); + *ascent = (float) i_ascent * scale; + *descent = (float) i_descent * scale; + *lineGap = (float) i_lineGap * scale; +} + +STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int align_to_integer) +{ + float ipw = 1.0f / pw, iph = 1.0f / ph; + const stbtt_packedchar *b = chardata + char_index; + + if (align_to_integer) { + float x = (float) STBTT_ifloor((*xpos + b->xoff) + 0.5f); + float y = (float) STBTT_ifloor((*ypos + b->yoff) + 0.5f); + q->x0 = x; + q->y0 = y; + q->x1 = x + b->xoff2 - b->xoff; + q->y1 = y + b->yoff2 - b->yoff; + } else { + q->x0 = *xpos + b->xoff; + q->y0 = *ypos + b->yoff; + q->x1 = *xpos + b->xoff2; + q->y1 = *ypos + b->yoff2; + } + + q->s0 = b->x0 * ipw; + q->t0 = b->y0 * iph; + q->s1 = b->x1 * ipw; + q->t1 = b->y1 * iph; + + *xpos += b->xadvance; +} + +////////////////////////////////////////////////////////////////////////////// +// +// sdf computation +// + +#define STBTT_min(a,b) ((a) < (b) ? (a) : (b)) +#define STBTT_max(a,b) ((a) < (b) ? (b) : (a)) + +static int stbtt__ray_intersect_bezier(float orig[2], float ray[2], float q0[2], float q1[2], float q2[2], float hits[2][2]) +{ + float q0perp = q0[1]*ray[0] - q0[0]*ray[1]; + float q1perp = q1[1]*ray[0] - q1[0]*ray[1]; + float q2perp = q2[1]*ray[0] - q2[0]*ray[1]; + float roperp = orig[1]*ray[0] - orig[0]*ray[1]; + + float a = q0perp - 2*q1perp + q2perp; + float b = q1perp - q0perp; + float c = q0perp - roperp; + + float s0 = 0., s1 = 0.; + int num_s = 0; + + if (a != 0.0) { + float discr = b*b - a*c; + if (discr > 0.0) { + float rcpna = -1 / a; + float d = (float) STBTT_sqrt(discr); + s0 = (b+d) * rcpna; + s1 = (b-d) * rcpna; + if (s0 >= 0.0 && s0 <= 1.0) + num_s = 1; + if (d > 0.0 && s1 >= 0.0 && s1 <= 1.0) { + if (num_s == 0) s0 = s1; + ++num_s; + } + } + } else { + // 2*b*s + c = 0 + // s = -c / (2*b) + s0 = c / (-2 * b); + if (s0 >= 0.0 && s0 <= 1.0) + num_s = 1; + } + + if (num_s == 0) + return 0; + else { + float rcp_len2 = 1 / (ray[0]*ray[0] + ray[1]*ray[1]); + float rayn_x = ray[0] * rcp_len2, rayn_y = ray[1] * rcp_len2; + + float q0d = q0[0]*rayn_x + q0[1]*rayn_y; + float q1d = q1[0]*rayn_x + q1[1]*rayn_y; + float q2d = q2[0]*rayn_x + q2[1]*rayn_y; + float rod = orig[0]*rayn_x + orig[1]*rayn_y; + + float q10d = q1d - q0d; + float q20d = q2d - q0d; + float q0rd = q0d - rod; + + hits[0][0] = q0rd + s0*(2.0f - 2.0f*s0)*q10d + s0*s0*q20d; + hits[0][1] = a*s0+b; + + if (num_s > 1) { + hits[1][0] = q0rd + s1*(2.0f - 2.0f*s1)*q10d + s1*s1*q20d; + hits[1][1] = a*s1+b; + return 2; + } else { + return 1; + } + } +} + +static int equal(float *a, float *b) +{ + return (a[0] == b[0] && a[1] == b[1]); +} + +static int stbtt__compute_crossings_x(float x, float y, int nverts, stbtt_vertex *verts) +{ + int i; + float orig[2], ray[2] = { 1, 0 }; + float y_frac; + int winding = 0; + + // make sure y never passes through a vertex of the shape + y_frac = (float) STBTT_fmod(y, 1.0f); + if (y_frac < 0.01f) + y += 0.01f; + else if (y_frac > 0.99f) + y -= 0.01f; + + orig[0] = x; + orig[1] = y; + + // test a ray from (-infinity,y) to (x,y) + for (i=0; i < nverts; ++i) { + if (verts[i].type == STBTT_vline) { + int x0 = (int) verts[i-1].x, y0 = (int) verts[i-1].y; + int x1 = (int) verts[i ].x, y1 = (int) verts[i ].y; + if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) { + float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0; + if (x_inter < x) + winding += (y0 < y1) ? 1 : -1; + } + } + if (verts[i].type == STBTT_vcurve) { + int x0 = (int) verts[i-1].x , y0 = (int) verts[i-1].y ; + int x1 = (int) verts[i ].cx, y1 = (int) verts[i ].cy; + int x2 = (int) verts[i ].x , y2 = (int) verts[i ].y ; + int ax = STBTT_min(x0,STBTT_min(x1,x2)), ay = STBTT_min(y0,STBTT_min(y1,y2)); + int by = STBTT_max(y0,STBTT_max(y1,y2)); + if (y > ay && y < by && x > ax) { + float q0[2],q1[2],q2[2]; + float hits[2][2]; + q0[0] = (float)x0; + q0[1] = (float)y0; + q1[0] = (float)x1; + q1[1] = (float)y1; + q2[0] = (float)x2; + q2[1] = (float)y2; + if (equal(q0,q1) || equal(q1,q2)) { + x0 = (int)verts[i-1].x; + y0 = (int)verts[i-1].y; + x1 = (int)verts[i ].x; + y1 = (int)verts[i ].y; + if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) { + float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0; + if (x_inter < x) + winding += (y0 < y1) ? 1 : -1; + } + } else { + int num_hits = stbtt__ray_intersect_bezier(orig, ray, q0, q1, q2, hits); + if (num_hits >= 1) + if (hits[0][0] < 0) + winding += (hits[0][1] < 0 ? -1 : 1); + if (num_hits >= 2) + if (hits[1][0] < 0) + winding += (hits[1][1] < 0 ? -1 : 1); + } + } + } + } + return winding; +} + +static float stbtt__cuberoot( float x ) +{ + if (x<0) + return -(float) STBTT_pow(-x,1.0f/3.0f); + else + return (float) STBTT_pow( x,1.0f/3.0f); +} + +// x^3 + a*x^2 + b*x + c = 0 +static int stbtt__solve_cubic(float a, float b, float c, float* r) +{ + float s = -a / 3; + float p = b - a*a / 3; + float q = a * (2*a*a - 9*b) / 27 + c; + float p3 = p*p*p; + float d = q*q + 4*p3 / 27; + if (d >= 0) { + float z = (float) STBTT_sqrt(d); + float u = (-q + z) / 2; + float v = (-q - z) / 2; + u = stbtt__cuberoot(u); + v = stbtt__cuberoot(v); + r[0] = s + u + v; + return 1; + } else { + float u = (float) STBTT_sqrt(-p/3); + float v = (float) STBTT_acos(-STBTT_sqrt(-27/p3) * q / 2) / 3; // p3 must be negative, since d is negative + float m = (float) STBTT_cos(v); + float n = (float) STBTT_cos(v-3.141592/2)*1.732050808f; + r[0] = s + u * 2 * m; + r[1] = s - u * (m + n); + r[2] = s - u * (m - n); + + //STBTT_assert( STBTT_fabs(((r[0]+a)*r[0]+b)*r[0]+c) < 0.05f); // these asserts may not be safe at all scales, though they're in bezier t parameter units so maybe? + //STBTT_assert( STBTT_fabs(((r[1]+a)*r[1]+b)*r[1]+c) < 0.05f); + //STBTT_assert( STBTT_fabs(((r[2]+a)*r[2]+b)*r[2]+c) < 0.05f); + return 3; + } +} + +STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff) +{ + float scale_x = scale, scale_y = scale; + int ix0,iy0,ix1,iy1; + int w,h; + unsigned char *data; + + if (scale == 0) return NULL; + + stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale, scale, 0.0f,0.0f, &ix0,&iy0,&ix1,&iy1); + + // if empty, return NULL + if (ix0 == ix1 || iy0 == iy1) + return NULL; + + ix0 -= padding; + iy0 -= padding; + ix1 += padding; + iy1 += padding; + + w = (ix1 - ix0); + h = (iy1 - iy0); + + if (width ) *width = w; + if (height) *height = h; + if (xoff ) *xoff = ix0; + if (yoff ) *yoff = iy0; + + // invert for y-downwards bitmaps + scale_y = -scale_y; + + { + // distance from singular values (in the same units as the pixel grid) + const float eps = 1./1024, eps2 = eps*eps; + int x,y,i,j; + float *precompute; + stbtt_vertex *verts; + int num_verts = stbtt_GetGlyphShape(info, glyph, &verts); + data = (unsigned char *) STBTT_malloc(w * h, info->userdata); + precompute = (float *) STBTT_malloc(num_verts * sizeof(float), info->userdata); + + for (i=0,j=num_verts-1; i < num_verts; j=i++) { + if (verts[i].type == STBTT_vline) { + float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y; + float x1 = verts[j].x*scale_x, y1 = verts[j].y*scale_y; + float dist = (float) STBTT_sqrt((x1-x0)*(x1-x0) + (y1-y0)*(y1-y0)); + precompute[i] = (dist < eps) ? 0.0f : 1.0f / dist; + } else if (verts[i].type == STBTT_vcurve) { + float x2 = verts[j].x *scale_x, y2 = verts[j].y *scale_y; + float x1 = verts[i].cx*scale_x, y1 = verts[i].cy*scale_y; + float x0 = verts[i].x *scale_x, y0 = verts[i].y *scale_y; + float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2; + float len2 = bx*bx + by*by; + if (len2 >= eps2) + precompute[i] = 1.0f / len2; + else + precompute[i] = 0.0f; + } else + precompute[i] = 0.0f; + } + + for (y=iy0; y < iy1; ++y) { + for (x=ix0; x < ix1; ++x) { + float val; + float min_dist = 999999.0f; + float sx = (float) x + 0.5f; + float sy = (float) y + 0.5f; + float x_gspace = (sx / scale_x); + float y_gspace = (sy / scale_y); + + int winding = stbtt__compute_crossings_x(x_gspace, y_gspace, num_verts, verts); // @OPTIMIZE: this could just be a rasterization, but needs to be line vs. non-tesselated curves so a new path + + for (i=0; i < num_verts; ++i) { + float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y; + + if (verts[i].type == STBTT_vline && precompute[i] != 0.0f) { + float x1 = verts[i-1].x*scale_x, y1 = verts[i-1].y*scale_y; + + float dist,dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy); + if (dist2 < min_dist*min_dist) + min_dist = (float) STBTT_sqrt(dist2); + + // coarse culling against bbox + //if (sx > STBTT_min(x0,x1)-min_dist && sx < STBTT_max(x0,x1)+min_dist && + // sy > STBTT_min(y0,y1)-min_dist && sy < STBTT_max(y0,y1)+min_dist) + dist = (float) STBTT_fabs((x1-x0)*(y0-sy) - (y1-y0)*(x0-sx)) * precompute[i]; + STBTT_assert(i != 0); + if (dist < min_dist) { + // check position along line + // x' = x0 + t*(x1-x0), y' = y0 + t*(y1-y0) + // minimize (x'-sx)*(x'-sx)+(y'-sy)*(y'-sy) + float dx = x1-x0, dy = y1-y0; + float px = x0-sx, py = y0-sy; + // minimize (px+t*dx)^2 + (py+t*dy)^2 = px*px + 2*px*dx*t + t^2*dx*dx + py*py + 2*py*dy*t + t^2*dy*dy + // derivative: 2*px*dx + 2*py*dy + (2*dx*dx+2*dy*dy)*t, set to 0 and solve + float t = -(px*dx + py*dy) / (dx*dx + dy*dy); + if (t >= 0.0f && t <= 1.0f) + min_dist = dist; + } + } else if (verts[i].type == STBTT_vcurve) { + float x2 = verts[i-1].x *scale_x, y2 = verts[i-1].y *scale_y; + float x1 = verts[i ].cx*scale_x, y1 = verts[i ].cy*scale_y; + float box_x0 = STBTT_min(STBTT_min(x0,x1),x2); + float box_y0 = STBTT_min(STBTT_min(y0,y1),y2); + float box_x1 = STBTT_max(STBTT_max(x0,x1),x2); + float box_y1 = STBTT_max(STBTT_max(y0,y1),y2); + // coarse culling against bbox to avoid computing cubic unnecessarily + if (sx > box_x0-min_dist && sx < box_x1+min_dist && sy > box_y0-min_dist && sy < box_y1+min_dist) { + int num=0; + float ax = x1-x0, ay = y1-y0; + float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2; + float mx = x0 - sx, my = y0 - sy; + float res[3] = {0.f,0.f,0.f}; + float px,py,t,it,dist2; + float a_inv = precompute[i]; + if (a_inv == 0.0) { // if a_inv is 0, it's 2nd degree so use quadratic formula + float a = 3*(ax*bx + ay*by); + float b = 2*(ax*ax + ay*ay) + (mx*bx+my*by); + float c = mx*ax+my*ay; + if (STBTT_fabs(a) < eps2) { // if a is 0, it's linear + if (STBTT_fabs(b) >= eps2) { + res[num++] = -c/b; + } + } else { + float discriminant = b*b - 4*a*c; + if (discriminant < 0) + num = 0; + else { + float root = (float) STBTT_sqrt(discriminant); + res[0] = (-b - root)/(2*a); + res[1] = (-b + root)/(2*a); + num = 2; // don't bother distinguishing 1-solution case, as code below will still work + } + } + } else { + float b = 3*(ax*bx + ay*by) * a_inv; // could precompute this as it doesn't depend on sample point + float c = (2*(ax*ax + ay*ay) + (mx*bx+my*by)) * a_inv; + float d = (mx*ax+my*ay) * a_inv; + num = stbtt__solve_cubic(b, c, d, res); + } + dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy); + if (dist2 < min_dist*min_dist) + min_dist = (float) STBTT_sqrt(dist2); + + if (num >= 1 && res[0] >= 0.0f && res[0] <= 1.0f) { + t = res[0], it = 1.0f - t; + px = it*it*x0 + 2*t*it*x1 + t*t*x2; + py = it*it*y0 + 2*t*it*y1 + t*t*y2; + dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy); + if (dist2 < min_dist * min_dist) + min_dist = (float) STBTT_sqrt(dist2); + } + if (num >= 2 && res[1] >= 0.0f && res[1] <= 1.0f) { + t = res[1], it = 1.0f - t; + px = it*it*x0 + 2*t*it*x1 + t*t*x2; + py = it*it*y0 + 2*t*it*y1 + t*t*y2; + dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy); + if (dist2 < min_dist * min_dist) + min_dist = (float) STBTT_sqrt(dist2); + } + if (num >= 3 && res[2] >= 0.0f && res[2] <= 1.0f) { + t = res[2], it = 1.0f - t; + px = it*it*x0 + 2*t*it*x1 + t*t*x2; + py = it*it*y0 + 2*t*it*y1 + t*t*y2; + dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy); + if (dist2 < min_dist * min_dist) + min_dist = (float) STBTT_sqrt(dist2); + } + } + } + } + if (winding == 0) + min_dist = -min_dist; // if outside the shape, value is negative + val = onedge_value + pixel_dist_scale * min_dist; + if (val < 0) + val = 0; + else if (val > 255) + val = 255; + data[(y-iy0)*w+(x-ix0)] = (unsigned char) val; + } + } + STBTT_free(precompute, info->userdata); + STBTT_free(verts, info->userdata); + } + return data; +} + +STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff) +{ + return stbtt_GetGlyphSDF(info, scale, stbtt_FindGlyphIndex(info, codepoint), padding, onedge_value, pixel_dist_scale, width, height, xoff, yoff); +} + +STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata) +{ + STBTT_free(bitmap, userdata); +} + +////////////////////////////////////////////////////////////////////////////// +// +// font name matching -- recommended not to use this +// + +// check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string +static stbtt_int32 stbtt__CompareUTF8toUTF16_bigendian_prefix(stbtt_uint8 *s1, stbtt_int32 len1, stbtt_uint8 *s2, stbtt_int32 len2) +{ + stbtt_int32 i=0; + + // convert utf16 to utf8 and compare the results while converting + while (len2) { + stbtt_uint16 ch = s2[0]*256 + s2[1]; + if (ch < 0x80) { + if (i >= len1) return -1; + if (s1[i++] != ch) return -1; + } else if (ch < 0x800) { + if (i+1 >= len1) return -1; + if (s1[i++] != 0xc0 + (ch >> 6)) return -1; + if (s1[i++] != 0x80 + (ch & 0x3f)) return -1; + } else if (ch >= 0xd800 && ch < 0xdc00) { + stbtt_uint32 c; + stbtt_uint16 ch2 = s2[2]*256 + s2[3]; + if (i+3 >= len1) return -1; + c = ((ch - 0xd800) << 10) + (ch2 - 0xdc00) + 0x10000; + if (s1[i++] != 0xf0 + (c >> 18)) return -1; + if (s1[i++] != 0x80 + ((c >> 12) & 0x3f)) return -1; + if (s1[i++] != 0x80 + ((c >> 6) & 0x3f)) return -1; + if (s1[i++] != 0x80 + ((c ) & 0x3f)) return -1; + s2 += 2; // plus another 2 below + len2 -= 2; + } else if (ch >= 0xdc00 && ch < 0xe000) { + return -1; + } else { + if (i+2 >= len1) return -1; + if (s1[i++] != 0xe0 + (ch >> 12)) return -1; + if (s1[i++] != 0x80 + ((ch >> 6) & 0x3f)) return -1; + if (s1[i++] != 0x80 + ((ch ) & 0x3f)) return -1; + } + s2 += 2; + len2 -= 2; + } + return i; +} + +static int stbtt_CompareUTF8toUTF16_bigendian_internal(char *s1, int len1, char *s2, int len2) +{ + return len1 == stbtt__CompareUTF8toUTF16_bigendian_prefix((stbtt_uint8*) s1, len1, (stbtt_uint8*) s2, len2); +} + +// returns results in whatever encoding you request... but note that 2-byte encodings +// will be BIG-ENDIAN... use stbtt_CompareUTF8toUTF16_bigendian() to compare +STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID) +{ + stbtt_int32 i,count,stringOffset; + stbtt_uint8 *fc = font->data; + stbtt_uint32 offset = font->fontstart; + stbtt_uint32 nm = stbtt__find_table(fc, offset, "name"); + if (!nm) return NULL; + + count = ttUSHORT(fc+nm+2); + stringOffset = nm + ttUSHORT(fc+nm+4); + for (i=0; i < count; ++i) { + stbtt_uint32 loc = nm + 6 + 12 * i; + if (platformID == ttUSHORT(fc+loc+0) && encodingID == ttUSHORT(fc+loc+2) + && languageID == ttUSHORT(fc+loc+4) && nameID == ttUSHORT(fc+loc+6)) { + *length = ttUSHORT(fc+loc+8); + return (const char *) (fc+stringOffset+ttUSHORT(fc+loc+10)); + } + } + return NULL; +} + +static int stbtt__matchpair(stbtt_uint8 *fc, stbtt_uint32 nm, stbtt_uint8 *name, stbtt_int32 nlen, stbtt_int32 target_id, stbtt_int32 next_id) +{ + stbtt_int32 i; + stbtt_int32 count = ttUSHORT(fc+nm+2); + stbtt_int32 stringOffset = nm + ttUSHORT(fc+nm+4); + + for (i=0; i < count; ++i) { + stbtt_uint32 loc = nm + 6 + 12 * i; + stbtt_int32 id = ttUSHORT(fc+loc+6); + if (id == target_id) { + // find the encoding + stbtt_int32 platform = ttUSHORT(fc+loc+0), encoding = ttUSHORT(fc+loc+2), language = ttUSHORT(fc+loc+4); + + // is this a Unicode encoding? + if (platform == 0 || (platform == 3 && encoding == 1) || (platform == 3 && encoding == 10)) { + stbtt_int32 slen = ttUSHORT(fc+loc+8); + stbtt_int32 off = ttUSHORT(fc+loc+10); + + // check if there's a prefix match + stbtt_int32 matchlen = stbtt__CompareUTF8toUTF16_bigendian_prefix(name, nlen, fc+stringOffset+off,slen); + if (matchlen >= 0) { + // check for target_id+1 immediately following, with same encoding & language + if (i+1 < count && ttUSHORT(fc+loc+12+6) == next_id && ttUSHORT(fc+loc+12) == platform && ttUSHORT(fc+loc+12+2) == encoding && ttUSHORT(fc+loc+12+4) == language) { + slen = ttUSHORT(fc+loc+12+8); + off = ttUSHORT(fc+loc+12+10); + if (slen == 0) { + if (matchlen == nlen) + return 1; + } else if (matchlen < nlen && name[matchlen] == ' ') { + ++matchlen; + if (stbtt_CompareUTF8toUTF16_bigendian_internal((char*) (name+matchlen), nlen-matchlen, (char*)(fc+stringOffset+off),slen)) + return 1; + } + } else { + // if nothing immediately following + if (matchlen == nlen) + return 1; + } + } + } + + // @TODO handle other encodings + } + } + return 0; +} + +static int stbtt__matches(stbtt_uint8 *fc, stbtt_uint32 offset, stbtt_uint8 *name, stbtt_int32 flags) +{ + stbtt_int32 nlen = (stbtt_int32) STBTT_strlen((char *) name); + stbtt_uint32 nm,hd; + if (!stbtt__isfont(fc+offset)) return 0; + + // check italics/bold/underline flags in macStyle... + if (flags) { + hd = stbtt__find_table(fc, offset, "head"); + if ((ttUSHORT(fc+hd+44) & 7) != (flags & 7)) return 0; + } + + nm = stbtt__find_table(fc, offset, "name"); + if (!nm) return 0; + + if (flags) { + // if we checked the macStyle flags, then just check the family and ignore the subfamily + if (stbtt__matchpair(fc, nm, name, nlen, 16, -1)) return 1; + if (stbtt__matchpair(fc, nm, name, nlen, 1, -1)) return 1; + if (stbtt__matchpair(fc, nm, name, nlen, 3, -1)) return 1; + } else { + if (stbtt__matchpair(fc, nm, name, nlen, 16, 17)) return 1; + if (stbtt__matchpair(fc, nm, name, nlen, 1, 2)) return 1; + if (stbtt__matchpair(fc, nm, name, nlen, 3, -1)) return 1; + } + + return 0; +} + +static int stbtt_FindMatchingFont_internal(unsigned char *font_collection, char *name_utf8, stbtt_int32 flags) +{ + stbtt_int32 i; + for (i=0;;++i) { + stbtt_int32 off = stbtt_GetFontOffsetForIndex(font_collection, i); + if (off < 0) return off; + if (stbtt__matches((stbtt_uint8 *) font_collection, off, (stbtt_uint8*) name_utf8, flags)) + return off; + } +} + +#if defined(__GNUC__) || defined(__clang__) +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wcast-qual" +#endif + +STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset, + float pixel_height, unsigned char *pixels, int pw, int ph, + int first_char, int num_chars, stbtt_bakedchar *chardata) +{ + return stbtt_BakeFontBitmap_internal((unsigned char *) data, offset, pixel_height, pixels, pw, ph, first_char, num_chars, chardata); +} + +STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index) +{ + return stbtt_GetFontOffsetForIndex_internal((unsigned char *) data, index); +} + +STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data) +{ + return stbtt_GetNumberOfFonts_internal((unsigned char *) data); +} + +STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset) +{ + return stbtt_InitFont_internal(info, (unsigned char *) data, offset); +} + +STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags) +{ + return stbtt_FindMatchingFont_internal((unsigned char *) fontdata, (char *) name, flags); +} + +STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2) +{ + return stbtt_CompareUTF8toUTF16_bigendian_internal((char *) s1, len1, (char *) s2, len2); +} + +#if defined(__GNUC__) || defined(__clang__) +#pragma GCC diagnostic pop +#endif + +#endif // STB_TRUETYPE_IMPLEMENTATION + + +// FULL VERSION HISTORY +// +// 1.25 (2021-07-11) many fixes +// 1.24 (2020-02-05) fix warning +// 1.23 (2020-02-02) query SVG data for glyphs; query whole kerning table (but only kern not GPOS) +// 1.22 (2019-08-11) minimize missing-glyph duplication; fix kerning if both 'GPOS' and 'kern' are defined +// 1.21 (2019-02-25) fix warning +// 1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics() +// 1.19 (2018-02-11) OpenType GPOS kerning (horizontal only), STBTT_fmod +// 1.18 (2018-01-29) add missing function +// 1.17 (2017-07-23) make more arguments const; doc fix +// 1.16 (2017-07-12) SDF support +// 1.15 (2017-03-03) make more arguments const +// 1.14 (2017-01-16) num-fonts-in-TTC function +// 1.13 (2017-01-02) support OpenType fonts, certain Apple fonts +// 1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual +// 1.11 (2016-04-02) fix unused-variable warning +// 1.10 (2016-04-02) allow user-defined fabs() replacement +// fix memory leak if fontsize=0.0 +// fix warning from duplicate typedef +// 1.09 (2016-01-16) warning fix; avoid crash on outofmem; use alloc userdata for PackFontRanges +// 1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges +// 1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints; +// allow PackFontRanges to pack and render in separate phases; +// fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?); +// fixed an assert() bug in the new rasterizer +// replace assert() with STBTT_assert() in new rasterizer +// 1.06 (2015-07-14) performance improvements (~35% faster on x86 and x64 on test machine) +// also more precise AA rasterizer, except if shapes overlap +// remove need for STBTT_sort +// 1.05 (2015-04-15) fix misplaced definitions for STBTT_STATIC +// 1.04 (2015-04-15) typo in example +// 1.03 (2015-04-12) STBTT_STATIC, fix memory leak in new packing, various fixes +// 1.02 (2014-12-10) fix various warnings & compile issues w/ stb_rect_pack, C++ +// 1.01 (2014-12-08) fix subpixel position when oversampling to exactly match +// non-oversampled; STBTT_POINT_SIZE for packed case only +// 1.00 (2014-12-06) add new PackBegin etc. API, w/ support for oversampling +// 0.99 (2014-09-18) fix multiple bugs with subpixel rendering (ryg) +// 0.9 (2014-08-07) support certain mac/iOS fonts without an MS platformID +// 0.8b (2014-07-07) fix a warning +// 0.8 (2014-05-25) fix a few more warnings +// 0.7 (2013-09-25) bugfix: subpixel glyph bug fixed in 0.5 had come back +// 0.6c (2012-07-24) improve documentation +// 0.6b (2012-07-20) fix a few more warnings +// 0.6 (2012-07-17) fix warnings; added stbtt_ScaleForMappingEmToPixels, +// stbtt_GetFontBoundingBox, stbtt_IsGlyphEmpty +// 0.5 (2011-12-09) bugfixes: +// subpixel glyph renderer computed wrong bounding box +// first vertex of shape can be off-curve (FreeSans) +// 0.4b (2011-12-03) fixed an error in the font baking example +// 0.4 (2011-12-01) kerning, subpixel rendering (tor) +// bugfixes for: +// codepoint-to-glyph conversion using table fmt=12 +// codepoint-to-glyph conversion using table fmt=4 +// stbtt_GetBakedQuad with non-square texture (Zer) +// updated Hello World! sample to use kerning and subpixel +// fixed some warnings +// 0.3 (2009-06-24) cmap fmt=12, compound shapes (MM) +// userdata, malloc-from-userdata, non-zero fill (stb) +// 0.2 (2009-03-11) Fix unsigned/signed char warnings +// 0.1 (2009-03-09) First public release +// + +/* +------------------------------------------------------------------------------ +This software is available under 2 licenses -- choose whichever you prefer. +------------------------------------------------------------------------------ +ALTERNATIVE A - MIT License +Copyright (c) 2017 Sean Barrett +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files (the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions: +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +------------------------------------------------------------------------------ +ALTERNATIVE B - Public Domain (www.unlicense.org) +This is free and unencumbered software released into the public domain. +Anyone is free to copy, modify, publish, use, compile, sell, or distribute this +software, either in source code form or as a compiled binary, for any purpose, +commercial or non-commercial, and by any means. +In jurisdictions that recognize copyright laws, the author or authors of this +software dedicate any and all copyright interest in the software to the public +domain. We make this dedication for the benefit of the public at large and to +the detriment of our heirs and successors. We intend this dedication to be an +overt act of relinquishment in perpetuity of all present and future rights to +this software under copyright law. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +------------------------------------------------------------------------------ +*/ diff --git a/docs/README.md b/docs/README.md index 927e151..03c5453 100644 --- a/docs/README.md +++ b/docs/README.md @@ -344,6 +344,15 @@ still to land. exact fade through the tint alpha, zero per-frame allocations, the `particle_render_10k` conversion budget (the 10k declare pass, both SimMath backends). +- [Bitmap font atlas](api/font.md) — + `laige::render::GlyphAtlas` (M2-TEXT-01, the bitmap half of + FR-2.8): the configured TTF/OTF font bytes + glyph range + rasterized ONCE at scene set-up (the vendored `stb_truetype` — + ADR 0009) into a fixed-size 8-bit alpha glyph atlas + per-glyph + metrics (advance, bearing, line height — documented px at 1x), + the deterministic shelf packing (same font + options → identical + atlas bytes), the missing-glyph fallback contract (never a crash, + never silent), and the zero-allocation O(1) `glyph(code)` lookup. ## Guides diff --git a/docs/api/font.md b/docs/api/font.md new file mode 100644 index 0000000..2a28650 --- /dev/null +++ b/docs/api/font.md @@ -0,0 +1,237 @@ +# Bitmap font atlas (`laige::render::GlyphAtlas`) + +The bitmap half of FR-2.8 — "Text rendering: ... bitmap (P0)" +(M2-TEXT-01): the caller's TTF/OTF font bytes + a configured glyph range +are rasterized **once, at scene set-up**, into a fixed-size 8-bit alpha +glyph atlas + per-glyph metrics (advance, bearing, line height). There +is **no runtime re-rasterization**: after `create`, `glyph(code)` is a +pure O(1) table lookup. The text widget / layout pass lands in +M2-TEXT-02; the SDF path (P1) lands in M2-TEXT-03 on top of the same +vendored rasterizer (ADR 0009). + +Public header: +`src/laige-render/include/laige/render/font.h` +(implementation: `src/laige-render/font.cpp`; the vendor boundary is +the `laige-stb` target — ADR 0009). Unit suite: `ctest -R font` +(`tests/laige-render/font_tests.cpp`) — pure engine data, no GL +environment required: it runs in every local tree and in CI, with the +validation matrix, the untrusted-font boundary, the capacity guard, +the metric goldens (measured against the committed test font — see +`tests/laige-render/assets/README.md`), the deterministic-atlas +contract, the missing-glyph fallback, and the zero-allocation lookup +window. + +## The API + +```cpp +// The per-glyph metrics + atlas cell origin (px at 1x). +struct GlyphMetrics { + std::int32_t advance{0}; // pen advance, px at 1x + std::int32_t bearingX{0}; // bitmap left edge from the pen (right +) + std::int32_t bearingY{0}; // bitmap top edge above the baseline (up +) + std::int32_t width{0}; // bitmap ink width, texels (0 = empty) + std::int32_t height{0}; // bitmap ink height, texels (0 = empty) + std::uint32_t atlasX{0}; // cell top-left, texels in the atlas + std::uint32_t atlasY{0}; +}; + +// The configured bitmap glyph atlas (move-only). +class GlyphAtlas { + public: + struct Options { + std::uint32_t atlasWidth{kFontDefaultAtlasWidth}; // 1024 + std::uint32_t atlasHeight{kFontDefaultAtlasHeight}; // 1024 + std::uint32_t fontSize{kFontDefaultFontSize}; // 16 px at 1x + std::uint32_t glyphFirst{kFontDefaultGlyphFirst}; // 32 (U+0020) + std::uint32_t glyphLast{kFontDefaultGlyphLast}; // 255 (Latin-1) + }; + + // Set-up path: validate, parse, rasterize (the only allocations). + [[nodiscard]] static Result create( + std::span font, Options options) noexcept; + + [[nodiscard]] bool valid() const noexcept; + [[nodiscard]] std::uint32_t atlasWidth() const noexcept; + [[nodiscard]] std::uint32_t atlasHeight() const noexcept; + [[nodiscard]] std::uint32_t fontSize() const noexcept; + [[nodiscard]] std::uint32_t lineHeight() const noexcept; // == fontSize() + [[nodiscard]] std::uint32_t glyphFirst() const noexcept; + [[nodiscard]] std::uint32_t glyphLast() const noexcept; + [[nodiscard]] std::span atlas() const noexcept; + [[nodiscard]] const GlyphMetrics* glyph(std::uint32_t code) const noexcept; +}; +``` + +Constants (`CORE-005`): `kFontMaxAtlasDimension` (4096), +`kFontMaxFontSize` (1024), `kFontMaxGlyphCode` (0x10FFFF), +`kFontMaxGlyphCount` (8192 — the range-size bound), +`kFontDefaultAtlasWidth/Height` (1024), `kFontDefaultFontSize` (16), +`kFontDefaultGlyphFirst/Last` (32..255, the Latin-1 set), +`kFontFallbackCode` (32 = U+0020 SPACE), `kFontEmptyGlyphMetrics` (the +zero metric). + +## Documented units + +All metric values are **pixels at 1x** — at the atlas's configured +`fontSize` (the stbtt pixel-height convention: the font's ascent + +descent scaled to exactly that height). To render at an integer scale +s, multiply every metric by s (exact for integer s); the atlas bitmap +is drawn at s× its texel size (the M2-SPRITE-02 sprite `scale`). + +- `advance` — the pen advance after the glyph (positive = right; a + negative value is stored as-is — RTL/quirk fonts are out of scope, + the field is total). +- `bearingX` — the bitmap's LEFT edge from the pen (right positive; + negative = the ink overhangs the pen left). Place the cell at + `penX + bearingX`. +- `bearingY` — the bitmap's TOP edge ABOVE the baseline (up positive). + The ink bottom is at `bearingY − height` below the baseline (a + descender when `height > bearingY`). +- `width`/`height` — the ink size in texels (`0 × 0` = the empty + glyph — nothing is drawn, the advance still applies). +- `lineHeight()` — the line height in px at 1x: **`lineHeight() == + fontSize()`** exactly (the documented formula, not a separate + measurement). + +## The atlas layout (deterministic shelf packing) + +The atlas is `atlasWidth × atlasHeight` texels of 8-bit alpha. +Codepoints are laid out in **ascending order**, one shelf row at a +time: the cursor starts at (0, 0); a glyph's cell is placed at the +cursor; the cursor advances right by the cell's width; when the cell +would not fit on the row it wraps to the next row (y advances by the +row's max cell height). A cell is **exactly the glyph's ink bitmap** +(no padding — the rasterization is clipped to the cell, so no glyph +can bleed into a neighbor; the M2-SPRITE-02 `GL_NEAREST` +"texel = floor(u·W)" contract applies). Empty glyphs occupy no cell +space. The packing is a pure function of (font bytes, options): +same input → **bit-identical atlas bytes** (the determinism test). + +`GlyphMetrics.atlasX/atlasY` is the cell's top-left texel; the glyph's +UV rect for the M2-SPRITE-02 upload is +`(atlasX/W, atlasY/H, (atlasX+width)/W, (atlasY+height)/H)` +(the M2-SPRITE-03 v-axis convention: v = 0 = first uploaded texel row). + +The atlas bytes are 8-bit alpha; the M2-TEXT-02 pass uploads them as a +white-on-alpha RGBA8 atlas through the M2-SPRITE-02 `bindAtlas` +path. + +## Missing glyphs (the documented fallback) + +`glyph(code)` is a **total function** — it never crashes and, for a +live atlas, never returns null: + +- `code` in `[glyphFirst, glyphLast]` → that codepoint's slot. A + codepoint the font does not carry maps to the font's `.notdef` + glyph (the stbtt unknown-codepoint → glyph 0 contract) — + deterministic per font. +- `code` OUTSIDE the range → the **fallback glyph**: the U+0020 space + slot if `kFontFallbackCode` lies in the configured range (the + default does), else `kFontEmptyGlyphMetrics` (the zero metric). +- The stopped atlas → `nullptr` (check `valid()` first). + +The fallback is documented, never silent: a game that wants a visible +"missing character" box configures a glyph range that includes its box +glyph — the engine does not draw extra glyphs. + +## Failure behavior (CORE-008) + +`create` validates in this order (first failure wins): + +1. **Options** (no log — the M2-SPRITE-01 create precedent): + `atlasWidth`/`atlasHeight` in `[1, 4096]`, `fontSize` in + `[1, 1024]`, `glyphFirst ≤ glyphLast ≤ 0x10FFFF`, + `(glyphLast − glyphFirst + 1) ≤ 8192` → `InvalidArgument`. +2. **Font bytes** (the untrusted-input boundary, SCALE-004): the + header + full table directory must be present (the engine-side + guard — stb's directory scan is not bounds-checked; the buf-based + table parsing is), the required tables must parse, and the + pixel-height scale (px per font unit) must be finite, positive, and + ≤ 2^15 (the int-domain ceiling — the reachable max is 1024; a font + with 0 or inverted vertical metrics makes it inf or negative) → + `MalformedInput` + one + structured Error `font/font_invalid` (field: `bytes`). A + truncated, non-font, or degenerate-metric file is an error, never + a crash and never a silent fallback. +3. **Capacity**: a glyph whose ink cell does not fit the fixed atlas + (wider/taller than the atlas, or the shelf is full) → + `BudgetExhausted` + one structured Error `font/atlas_full` + (fields: `code`, `width`, `height`, `atlas_width`, `atlas_height`). + The atlas is fixed-size by contract: grow the atlas, not the font. +4. Success → one Info `font/atlas_created` (the set-up path is + low-volume; the lookup path logs nothing). + +A failed create returns the error; no atlas is produced. + +## Ownership, threading (CORE-009, CONC-001) + +`GlyphAtlas` owns its atlas bytes + slot table (move-only, the +`SpriteBatcher` precedent). One owner (the scene set-up thread); the +render phase reads it (the M2-GL-02 cull/batch stage uploads the atlas ++ declares text quads — M2-TEXT-02). The font bytes are a +**non-owning span**: the caller owns them (the game's asset pipeline — +the M3 asset system); they are read only during `create` and may be +freed immediately after. Presentation-only (ARCH-009): the atlas is +never part of the sim state hash or replay state. No GL calls +anywhere in this API. + +## Performance (DOC-004) + +- `create` (set-up path, once per scene): O(glyphs × glyph-area) + rasterization — 224 glyphs × 16 px ≈ a few ms for the default Latin-1 + range; the two allocations are the atlas bytes (1 MiB at the default + 1024²) + the slot table (28 B per codepoint — 6.3 KB for Latin-1). + The per-glyph `stbtt` bitmap buffer is a transient ≤ 16 777 216 + bytes (atlasWidth × atlasHeight, the capacity-bounded guard — never + an int overflow, never an unbounded malloc). +- `glyph(code)` (render read path, per text quad per frame): **O(1), + no allocation, no logging, no GL** — a bounds check + a pointer + return (the zero-allocation test: 1000 mixed lookups = 0 heap + blocks). The returned pointer is valid until the atlas is + moved/destroyed (the slot table is never reallocated after create). +- No `budgets.json` entry: the atlas is built once at set-up, not per + frame — the per-frame text cost lands with M2-TEXT-02 (part of the + composite 50k render-CPU budget, M2-PERF-01). + +**Common trap:** rasterizing in a per-frame code path. The atlas is a +set-up artifact — `create` per frame re-parses and re-rasterizes the +font (the FR-2.8 "no runtime re-rasterization" contract exists for +this reason). + +## Example (performant path) + +```cpp +// Scene set-up (once): read the font file (the asset pipeline owns +// the bytes), build the atlas, upload it (M2-TEXT-02), and keep the +// GlyphAtlas for the frame pipeline's declaration stage. +std::vector fontBytes = readAsset("fonts/vera.ttf"); +auto atlas = laige::render::GlyphAtlas::create(fontBytes, + laige::render::GlyphAtlas::Options{}); +if (atlas.isError()) { /* handle: the font asset is invalid */ } +fontBytes.clear(); // safe: the atlas owns a copy of the bitmap +// Per frame (M2-TEXT-02): one quad per drawn glyph — +// metrics = atlas.glyph(code); quad uv = (atlasX/W, atlasY/H, +// (atlasX+width)/W, (atlasY+height)/H); advance pen by advance * scale. +``` + +## Misuse warnings + +- Do not free the font bytes before `create` returns (the span is + non-owning, read during creation). +- Do not `create` per frame — build the atlas once at scene set-up. +- Do not assume `glyph(code)` covers a codepoint: the range is + configured (default Latin-1); outside-range codes fall back to the + space glyph (the documented contract), they are never rasterized on + demand. +- Do not reuse the pointer from `glyph()` after the atlas is moved + (the slot table storage moves with the atlas). + +## Related + +- [`sprite_batcher.md`](sprite_batcher.md) — the batcher the M2-TEXT-02 + text quads are declared into. +- [`sprite_frames.md`](sprite_frames.md) — the atlas UV conventions + (the v-axis, the float-exact domain). +- [`particle_render.md`](particle_render.md) — the sibling render-phase + declaration pass (the pattern M2-TEXT-02 follows). +- ADR 0009 — the stb_truetype vendoring (the dependency this step adds). diff --git a/docs/decisions/0009-stb-truetype-vendoring.md b/docs/decisions/0009-stb-truetype-vendoring.md new file mode 100644 index 0000000..278264c --- /dev/null +++ b/docs/decisions/0009-stb-truetype-vendoring.md @@ -0,0 +1,180 @@ +# ADR 0009 — Vendoring stb_truetype as the font rasterizer + +- **Status:** Accepted +- **Date:** 2026-10-08 +- **Decider:** Roadmap step M2-TEXT-01 +- **Refs:** PRD §11 (dependency table, "font rasterization: stb_truetype"), + FR-2.8 (bitmap text P0), AGENTS DEP-003/DEP-004/DEP-005, roadmap + M2-TEXT-01, ADR 0004 (the vendoring machinery this reuses), ADR 0007 + (the sibling vendor: same `deps.lock` mechanism), ADR 0008 (the + header-only contrast documented in §Consequences) + +## Context + +M2-TEXT-01 lands bitmap font rasterization (FR-2.8 P0): the configured +font + glyph set is rasterized at scene set-up into a fixed-size bitmap +glyph atlas with per-glyph metrics (advance, bearing, line height). The +PRD pre-approves **stb_truetype** as the font rasterizer (PRD §11), so +no PRD revision is required — only the DEP-003 documentation and the +DEP-005 pinning, which this ADR and `deps.lock` provide. + +Two constraints shape the decision: + +1. **NFR-8.8 forbids network access at build time**, so the header is + vendored in-tree and verified by the `deps.lock` tree hash on every + configure (the ADR 0004 machinery, the same treatment as GLFW/GLAD in + ADR 0007 and GLM in ADR 0008). +2. **The public API must not name vendor types** (CPP-010, DEP-004): + unlike GLM (ADR 0008), the font API exposes engine-owned metric + structs and atlas bytes, never `stbtt_fontinfo` or other vendor + types — the rasterizer sits behind an implementation boundary. + +## Decision + +- Vendor **stb_truetype** from upstream commit + `2c980bb59875b0d32144a71867fbdebb2f77cd20` (2026-08-01; stb publishes + no release tags, so the pin is the commit, recorded in `deps.lock` + `source_commit`) under `deps/stb/` — exactly two files: + `stb_truetype.h` (the complete single-header library) and `LICENSE` + (the upstream license text). No other stb headers are vendored: + M2-TEXT-01/02/03 need only font rasterization, and the tree hash + covers what is actually consumed (CORE-004: no speculative surface). +- stb_truetype is a **single-header library with a one-translation-unit + implementation**: the engine's `laige-stb` static target compiles the + pinned header once with `STB_TRUETYPE_IMPLEMENTATION` + (`src/laige-render/stb_truetype_impl.cpp`) under the **plain compiler + policy** — pinned vendor code, DEP-005, the `laige-glad` precedent + (ADR 0007): the engine's `-Wall -Werror` policy does not gate upstream + code, and the vendor tree stays byte-pinned by the lock. +- The engine boundary is `src/laige-render/font.cpp` (+ the public + header `src/laige-render/include/laige/render/font.h`): it includes + the vendor header's **declarations** privately and links `laige-stb` + PRIVATE. The public header names no stb type, so consumers never see + vendor code (CPP-010) and no other module may include `deps/stb` + (the include-graph lint R3 owner rule, `owner: src/laige-render`). +- Pin in `deps.lock` (tree SHA-256 `8f065846…`, source URL + commit, + stb license, justification); the root `CMakeLists.txt` runs + `laige_deps_verify_lock()` on every configure and fails loudly on any + mismatch (CORE-008, DEP-005). +- The engine uses only the **font-metrics + glyph-bitmap surface**: + `stbtt_GetFontOffsetForIndex` (0 = the first font in the file, −1 = + not a font), `stbtt_InitFont`, `stbtt_ScaleForPixelHeight`, + `stbtt_FindGlyphIndex` (0 = `.notdef` — stbtt's unknown-codepoint + contract), `stbtt_GetGlyphHMetrics` (unscaled integer advance), + `stbtt_GetGlyphBitmapBox` (no allocation), `stbtt_GetGlyphBitmap` + (the only allocating call — one transient `w × h` 8-bit buffer per + glyph, freed by the engine's RAII wrapper). Nothing else of the + 40k-line header (outline parsing internals, subsetting, the + "STB_truetype" visualization modes) is called by engine code. Note + the pinned commit's API differs from older stb versions: there is no + `stbtt_GetFontOffsetForData` and no per-codepoint convenience + wrappers (the glyph index + metrics surface is the API). + +## DEP-003 justification + +- **Capability needed:** a maintained, dependency-free, cross-platform + TTF/OTF rasterizer that turns a caller-supplied font byte buffer into + 8-bit alpha glyph bitmaps + exact metrics at a configured pixel + height, with no runtime state (the atlas is built once at scene + set-up — no runtime re-rasterization, M2-TEXT-01 scope) and no GL + calls. +- **Alternatives considered:** + - *FreeType* — the full-featured incumbent, but a compiled C library + with a long build configuration (autoconf/meson), a large transitive + surface, and far more than M2-TEXT-01 needs (it parses the entire + OpenType spec for features this engine does not use). It is the + PRD §11 escape hatch if bitmap text ever needs TrueType hinting or + OpenType layout features; it is not the P0 path. + - *Hand-written TTF outline rasterizer* — rejected: font-outline + parsing + scanline fill is exactly the mature, error-prone, + format-heavy work DEP-002 says not to reinvent. + - *Pre-rasterized atlas files (no runtime rasterizer)* — rejected: + FR-2.8 requires the CONFIGURED font (the game's font asset), not a + baked-in one; and M2-TEXT-03 (SDF) needs the outline data again, + which a baked atlas would not provide. +- **Transitive dependencies:** none (single header, C99, no submodules, + no build-time tool). Build impact: one extra static target + (`laige-stb`) + the vendor header compiled once — seconds of compile + time in the Debug trees, no system packages. +- **Platforms / health / license:** stb — the de-facto standard + single-header C library collection (nothings/stb, 15+ years, used + across the C/C++ rendering ecosystem); `stb_truetype.h` is one of its + most widely deployed headers. **License:** stb's no-warranty license + (permissive, no copyleft, compatible with the engine's MIT license, + NFR-1.2) — the text is committed at `deps/stb/LICENSE`. +- **Security:** the rasterizer parses caller-supplied font bytes + (untrusted input, SCALE-004): `GlyphAtlas::create` validates the + bytes at the boundary — the header + full table directory must be + present (the engine-side guard: stbtt's table-directory scan is not + bounds-checked in the pinned commit, so the guard runs before any + stb call), and `stbtt_GetFontOffsetForIndex`/`stbtt_InitFont` reject + non-fonts before any parsing — the glyph range and atlas capacity are + bounded and validated, and the bitmap buffer size is derived from the + font's own (validated) metrics — a malformed font yields an error + Status, never a crash. Fuzz surface: the font loader is an + untrusted-input surface; a `laige-fuzz` font target is the M3-asset + step's concern (the loader consumes game assets after the M3 asset + system lands). +- **Upgrade/removal strategy:** re-vendor the pinned commit's + `stb_truetype.h` + `LICENSE`, recompute the tree hash, update + `deps.lock`, re-run CI (DEP-005). The engine-facing surface is the + engine's own `font.h` (stable names, metric structs); a stb upgrade + cannot move it, so the upgrade is a lock + CI change only. Removal + would mean adopting the FreeType alternative — a PRD §11 revision and + a new ADR. + +## Evidence + +- Vendored tree verified: the `deps.lock` hash check passes at configure + time in every local tree (all six, M2-TEXT-01 validation); the + include-graph lint reports the dependency: `stb 2026-08-01 — owner: + src/laige-render`, total vendored deps 5 (budget 10, PRD §11), no + non-owner include edge. +- Warning-clean: `laige-stb` compiles the pinned header under the plain + compiler policy in the GCC 16 and Clang 23 Debug trees (2026-10-08); + `font.cpp` compiles under the engine policy (`-Wall -Werror`) in all + six local trees with zero diagnostics. +- The M2-TEXT-01 unit suite pins the behavior: deterministic atlas + generation (same font + size → identical atlas bytes), the exact + metrics goldens, the missing-glyph fallback (never a crash), and the + stopped/capacity failure paths — CTest entry `font`, green in all six + local trees. + +## Consequences + +- **The vendor type stays behind the boundary** — a deliberate + parallel to the GLFW/GLAD pimpl treatment (ADR 0007) and a contrast + to ADR 0008: GLM value types are part of the public API because they + are versioned PODs; `stbtt_fontinfo` is an opaque, version-pinned C + struct whose layout is an upstream implementation detail, so it + stays in `font.cpp`. The public API is `GlyphAtlas`/`GlyphMetrics` + (engine-owned, stable). +- **One extra target, one extra lock entry:** the dependency count is + 5/10 (googletest, glfw, glad, glm, stb). +- **NFR-8.9 (shared builds):** `laige-stb` is a static archive linked + PRIVATE into `laige-render` (static or shared) — no public link + interface change, no ODR surface. +- **M2-TEXT-02/03 build on this:** M2-TEXT-02 (text items) consumes the + metrics + 8-bit alpha atlas (uploading it as an RGBA8 white-on-alpha + atlas to the M2-SPRITE-02 `bindAtlas` path); M2-TEXT-03 (SDF) reuses + the SAME vendored header (outline → distance field) — no new + dependency. +- **Determinism scope:** the atlas is presentation-only (ARCH-009): + rasterization is a fixed float sequence per (font bytes, options) — + bit-identical across runs of the same build (the in-process + determinism test pins this); cross-platform bit-identity is NOT + promised (render-side float, not SimMath — the same scope as the + M2-PROJ-01/ISO-03 float transforms). + +## Review conditions + +- Upgrade stb only via a DEP-005 change (new commit → new tree hash → + lock update → CI green); the engine-facing API (`font.h`) is + unchanged by such an upgrade, and `laige-api.json` regeneration + confirms the manifest. +- If FR-2.8 ever needs TrueType hinting, OpenType layout (kerning + pairs, GSUB), or a non-Latin-1 default glyph set, revisit the + FreeType alternative with its own ADR (PRD §11 row). +- If M2-TEXT-03's SDF path turns out to need stb internals beyond the + outline surface already vendored, re-scope the vendored file set in + the same PR (tree hash + this ADR). diff --git a/docs/decisions/README.md b/docs/decisions/README.md index 90d7521..a9cf86d 100644 --- a/docs/decisions/README.md +++ b/docs/decisions/README.md @@ -15,3 +15,4 @@ alternatives, evidence, consequences, and review conditions; the full | [0006](0006-ui-scope.md) | M2 retained UI widget set: the seven FR-2.8 widgets (D-UI) | Accepted | 2026-09-25 | | [0007](0007-glfw-glad-vendoring.md) | Vendoring GLFW 3.5.1 and the GLAD 2.0.8-generated GL 3.3 loader | Accepted | 2026-09-28 | | [0008](0008-glm-vendoring.md) | Vendoring GLM 1.0.3 as the rendering-side math library | Accepted | 2026-09-29 | +| [0009](0009-stb-truetype-vendoring.md) | Vendoring stb_truetype as the font rasterizer | Accepted | 2026-10-08 | diff --git a/laige-api.json b/laige-api.json index d4e243b..9497eef 100644 --- a/laige-api.json +++ b/laige-api.json @@ -15,6 +15,7 @@ "src/laige-core/include/laige/sim_math.h", "src/laige-render/include/laige/render/camera.h", "src/laige-render/include/laige/render/depth_sort.h", + "src/laige-render/include/laige/render/font.h", "src/laige-render/include/laige/render/frame_pipeline.h", "src/laige-render/include/laige/render/gl_context.h", "src/laige-render/include/laige/render/iso_camera.h", @@ -508,6 +509,49 @@ {"name": "laige::render::DepthSort::operator=", "kind": "method", "header": "src/laige-render/include/laige/render/depth_sort.h", "line": 261, "signature": "DepthSort& operator=(const DepthSort&) = delete", "summary": null, "budget": null, "experimental": false}, {"name": "laige::render::DepthSort::DepthSort", "kind": "constructor", "header": "src/laige-render/include/laige/render/depth_sort.h", "line": 267, "signature": "DepthSort(DepthSort&& other) noexcept", "summary": "Explicit move (the raw buffer pointers make the defaulted move unsafe for the moved-from object — it would dangle into the destination, the IsoDepthKeyTable pattern): the owner moves with the storage; the source becomes empty (buffers null, count 0, capacity 0 — CORE-009).", "budget": null, "experimental": false}, {"name": "laige::render::DepthSort::operator=", "kind": "method", "header": "src/laige-render/include/laige/render/depth_sort.h", "line": 268, "signature": "DepthSort& operator=(DepthSort&& other) noexcept", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontMaxAtlasDimension", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 145, "signature": "inline constexpr std::uint32_t kFontMaxAtlasDimension = 4096", "summary": "Named constants (CORE-005).", "budget": null, "experimental": false}, + {"name": "laige::render::kFontMaxFontSize", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 150, "signature": "inline constexpr std::uint32_t kFontMaxFontSize = 1024", "summary": "The configured pixel-height domain: [1, kFontMaxFontSize] px at 1x. 1024 px is beyond any practical UI text size; the rasterizer's float domain (the pixel box stays < 2^31 for every unitsPerEm) is never approached.", "budget": null, "experimental": false}, + {"name": "laige::render::kFontMaxGlyphCode", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 155, "signature": "inline constexpr std::uint32_t kFontMaxGlyphCode = 0x10FFFF", "summary": "The glyph-range domain: codepoints up to U+10FFFF (the Unicode ceiling); the RANGE SIZE is bounded by kFontMaxGlyphCount (a full 1.1M-codepoint range would rasterize minutes of set-up work — the documented budget guardrail, PERF-008).", "budget": null, "experimental": false}, + {"name": "laige::render::kFontMaxGlyphCount", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 156, "signature": "inline constexpr std::uint32_t kFontMaxGlyphCount = 8192", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontDefaultAtlasWidth", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 160, "signature": "inline constexpr std::uint32_t kFontDefaultAtlasWidth = 1024", "summary": "The defaults (the Latin-1 set, the FR-2.8 P0 scope: 32..126 printable ASCII + 160..255 the Latin-1 supplement; 127..159 C1 controls rasterize to the font's .notdef — harmless, deterministic).", "budget": null, "experimental": false}, + {"name": "laige::render::kFontDefaultAtlasHeight", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 161, "signature": "inline constexpr std::uint32_t kFontDefaultAtlasHeight = 1024", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontDefaultFontSize", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 162, "signature": "inline constexpr std::uint32_t kFontDefaultFontSize = 16", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontDefaultGlyphFirst", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 163, "signature": "inline constexpr std::uint32_t kFontDefaultGlyphFirst = 32", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontDefaultGlyphLast", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 164, "signature": "inline constexpr std::uint32_t kFontDefaultGlyphLast = 255", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::kFontFallbackCode", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 166, "signature": "inline constexpr std::uint32_t kFontFallbackCode = 32", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics", "kind": "struct", "header": "src/laige-render/include/laige/render/font.h", "line": 171, "signature": "struct GlyphMetrics", "summary": "Per-glyph metrics + the atlas cell origin (px at 1x, the header preamble). Plain value: no ownership, no lifetime beyond the atlas that stores it.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::advance", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 172, "signature": "std::int32_t advance{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::bearingX", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 173, "signature": "std::int32_t bearingX{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::bearingY", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 174, "signature": "std::int32_t bearingY{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::width", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 175, "signature": "std::int32_t width{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::height", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 176, "signature": "std::int32_t height{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::atlasX", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 177, "signature": "std::uint32_t atlasX{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::atlasY", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 178, "signature": "std::uint32_t atlasY{0}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphMetrics::operator==", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 182, "signature": "[[nodiscard]] bool operator==(const GlyphMetrics& other) const noexcept", "summary": "Field-wise equality (the deterministic-comparison test needs it; the house idiom — no synthesized ==, the SpriteUvRect precedent).", "budget": null, "experimental": false}, + {"name": "laige::render::kFontEmptyGlyphMetrics", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 192, "signature": "inline constexpr GlyphMetrics kFontEmptyGlyphMetrics{}", "summary": "The zero metric: the out-of-range fallback when the configured glyph range does not include the fallback code (the header preamble).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas", "kind": "class", "header": "src/laige-render/include/laige/render/font.h", "line": 195, "signature": "class GlyphAtlas", "summary": "The configured bitmap glyph atlas (M2-TEXT-01).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options", "kind": "struct", "header": "src/laige-render/include/laige/render/font.h", "line": 199, "signature": "struct Options", "summary": "The create options (API-006): see the header preamble for the documented units.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options::atlasWidth", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 200, "signature": "std::uint32_t atlasWidth{kFontDefaultAtlasWidth}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options::atlasHeight", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 201, "signature": "std::uint32_t atlasHeight{kFontDefaultAtlasHeight}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options::fontSize", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 202, "signature": "std::uint32_t fontSize{kFontDefaultFontSize}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options::glyphFirst", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 203, "signature": "std::uint32_t glyphFirst{kFontDefaultGlyphFirst}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::Options::glyphLast", "kind": "variable", "header": "src/laige-render/include/laige/render/font.h", "line": 204, "signature": "std::uint32_t glyphLast{kFontDefaultGlyphLast}", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::create", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 221, "signature": "[[nodiscard]] static laige::Result create(std::span font, Options options) noexcept", "summary": "Rasterizes the configured glyph range of `font` into the atlas (set-up path — the only allocations: the atlas bytes + the slot table). Validation order, first failure wins: 1. atlasWidth/atlasHeight in [1, kFontMaxAtlasDimension], fontSize in [1, kFontMaxFontSize], glyphFirst ≤ glyphLast ≤ kFontMaxGlyphCode, (glyphLast − glyphFirst + 1) ≤ kFontMaxGlyphCount (InvalidArgument, no log — the M2-SPRITE-01 create precedent); 2. the font bytes: a non-font / truncated / corrupt file → MalformedInput + one Error `font/font_invalid`; 3. a glyph whose cell does not fit the fixed atlas → BudgetExhausted + one Error `font/atlas_full` (fields: the codepoint, its cell size, the atlas size). A failed create returns the error; no atlas is produced.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::GlyphAtlas", "kind": "constructor", "header": "src/laige-render/include/laige/render/font.h", "line": 227, "signature": "GlyphAtlas() noexcept = default", "summary": "The stopped state (default / moved-from): `valid()` false, `glyph()` returns null, `atlas()` empty, introspection zero — the RenderThread stopped-state precedent. Nothing owned.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::GlyphAtlas", "kind": "constructor", "header": "src/laige-render/include/laige/render/font.h", "line": 229, "signature": "GlyphAtlas(const GlyphAtlas&) = delete", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::operator=", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 230, "signature": "GlyphAtlas& operator=(const GlyphAtlas&) = delete", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::GlyphAtlas", "kind": "constructor", "header": "src/laige-render/include/laige/render/font.h", "line": 231, "signature": "GlyphAtlas(GlyphAtlas&&) noexcept = default", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::operator=", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 232, "signature": "GlyphAtlas& operator=(GlyphAtlas&&) noexcept = default", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::~GlyphAtlas", "kind": "destructor", "header": "src/laige-render/include/laige/render/font.h", "line": 233, "signature": "~GlyphAtlas() noexcept = default", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::valid", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 236, "signature": "[[nodiscard]] bool valid() const noexcept", "summary": "True iff the atlas is live (create succeeded).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::atlasWidth", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 239, "signature": "[[nodiscard]] std::uint32_t atlasWidth() const noexcept", "summary": "The atlas dimensions (texels; zero in the stopped state).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::atlasHeight", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 240, "signature": "[[nodiscard]] std::uint32_t atlasHeight() const noexcept", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::fontSize", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 243, "signature": "[[nodiscard]] std::uint32_t fontSize() const noexcept", "summary": "The configured pixel height, px at 1x.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::lineHeight", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 247, "signature": "[[nodiscard]] std::uint32_t lineHeight() const noexcept", "summary": "The line height, px at 1x: `fontSize()` (the stbtt pixel-height convention — the header preamble).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::glyphFirst", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 250, "signature": "[[nodiscard]] std::uint32_t glyphFirst() const noexcept", "summary": "The configured glyph range (inclusive).", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::glyphLast", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 251, "signature": "[[nodiscard]] std::uint32_t glyphLast() const noexcept", "summary": null, "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::atlas", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 257, "signature": "[[nodiscard]] std::span atlas() const noexcept", "summary": "The atlas bytes: 8-bit alpha, row-major, `atlasWidth() × atlasHeight()` texels (empty in the stopped state). The render read path: the M2-TEXT-02 pass uploads this as a white-on-alpha RGBA8 atlas (the M2-SPRITE-02 `bindAtlas` contract). O(1); never writes.", "budget": null, "experimental": false}, + {"name": "laige::render::GlyphAtlas::glyph", "kind": "method", "header": "src/laige-render/include/laige/render/font.h", "line": 267, "signature": "[[nodiscard]] const GlyphMetrics* glyph(std::uint32_t code) const noexcept", "summary": "The metrics for `code` (the header preamble: a total function — null only in the stopped state; the in-range slot, else the documented fallback). O(1); no allocation, no logging, no GL. The returned pointer is valid until this atlas is moved/destroyed (the slot table is member storage, never reallocated after create).", "budget": null, "experimental": false}, {"name": "laige::render::FrameDescriptor", "kind": "struct", "header": "src/laige-render/include/laige/render/frame_pipeline.h", "line": 261, "signature": "struct FrameDescriptor", "summary": "One presentation frame's handed-off data (PRD §10.2: the frame descriptor of the lock-free handoff). A 32-byte POD — one plain copy per publish (PERF-005: no pointer graph, no allocation).", "budget": null, "experimental": false}, {"name": "laige::render::FrameDescriptor::frameIndex", "kind": "variable", "header": "src/laige-render/include/laige/render/frame_pipeline.h", "line": 264, "signature": "std::uint64_t frameIndex{}", "summary": "The producer's 1-based frame counter (see the header ownership section).", "budget": null, "experimental": false}, {"name": "laige::render::FrameDescriptor::simTick", "kind": "variable", "header": "src/laige-render/include/laige/render/frame_pipeline.h", "line": 267, "signature": "std::uint64_t simTick{}", "summary": "The last completed sim tick at publish time (0 before the first tick — the GameLoop's currentTick() value).", "budget": null, "experimental": false}, diff --git a/roadmap/M2-rendering-2.5d.md b/roadmap/M2-rendering-2.5d.md index ee4c8ae..5211285 100644 --- a/roadmap/M2-rendering-2.5d.md +++ b/roadmap/M2-rendering-2.5d.md @@ -250,7 +250,7 @@ if M2 slips, and its status is recorded in M2-EXIT-01. ## Text & UI -- [ ] **M2-TEXT-01 · Font rasterization (bitmap, P0)** +- [x] **M2-TEXT-01 · Font rasterization (bitmap, P0)** - **Refs:** FR-2.8 (bitmap P0; SDF is P1 → M2-TEXT-03), PRD §11 (stb_truetype) - **Depends:** M2-GL-01 - **Scope:** @@ -259,6 +259,20 @@ if M2 slips, and its status is recorded in M2-EXIT-01. - Unit tests: atlas generation deterministic (same font+size → identical atlas bytes); missing glyph → documented fallback glyph, never crash. - **Verify:** `ctest -R font` green. - **Size:** ~200 lines + tests + - **Shipped:** M2-TEXT-01 (`laige/render/font.h`, the `laige-stb` + target — ADR 0009): the font bytes + `GlyphAtlas::Options` + (default 1024², 16 px, Latin-1 32..255) rasterize ONCE at scene + set-up into a fixed 8-bit alpha atlas (deterministic shelf + packing) + per-glyph `GlyphMetrics` (advance, bearingX/Y, + width/height — px at 1x; `lineHeight() == fontSize()`); the + untrusted-font guard (header + table directory, SCALE-004), the + documented failure order (InvalidArgument → MalformedInput → + BudgetExhausted), the fallback contract (out-of-range → the U+0020 + space slot, else the zero metric; in-range unknown → the font's + .notdef), and the zero-alloc O(1) `glyph(code)` lookup (the + `font` suite: validation matrix, metric goldens against the + committed Vera test font, the deterministic-atlas bytes, the + fallback matrix, the 1000-lookup zero-alloc window). - [ ] **M2-TEXT-02 · Text items in the UI pass** - **Refs:** FR-2.8 (text widget, screen-space pass) diff --git a/roadmap/README.md b/roadmap/README.md index abb28a7..e682d01 100644 --- a/roadmap/README.md +++ b/roadmap/README.md @@ -157,7 +157,7 @@ Updated in the same PR that closes steps. "Done" = box checked + Verify green. |---|---|---|---| | M0 | 22 | 22 | ✅ complete (2026-09-13, M0-EXIT-01) | | M1 | 25 | 25 | ✅ complete (M1-EXIT-01, 2026-09-25) | -| M2 | 33 | 21 | ⬜ in progress | +| M2 | 33 | 22 | ⬜ in progress | | M3 | 36 | 0 | ⬜ not started | | M4 | 12 | 0 | ⬜ not started | | M5 | 21 | 0 | ⬜ not started | @@ -165,7 +165,7 @@ Updated in the same PR that closes steps. "Done" = box checked + Verify green. | M7 | 15 | 0 | ⬜ not started | | M8 | 8 | 0 | ⬜ not started | | M9 | 6 | 0 | ⬜ proposals only | -| **Total** | **194** | **67** | | +| **Total** | **194** | **68** | | --- @@ -246,6 +246,7 @@ One line per completed (or split/renumbered) step. | 2026-10-07 | M2-PART-01 | `—` / PR (open) | Particle simulation (CPU, 2D + depth) (FR-2.7 — "CPU-simulated, budgeted, pooled"; M2-PART-01 scope, nothing else): **API** — NEW `laige::ParticleSystem` (header-only, templated over the SimMath backends — the `presentation.h` pattern; `src/laige-sim/include/laige/sim/particles.h`) + `ParticleEmitterDef` (the spawn-domain value: `origin` (the spawn position — a particle spawns exactly here, no position jitter in M2-PART-01), `depth` (constant over life — the M2-ISO-01 depth-key input M2-PART-02 feeds the batcher), `velMin`/`velMax` (the per-tick velocity box, componentwise), `lifeMin`/`lifeMax` (sim ticks), `sizeMin`/`sizeMax` (world units), `tint[4]` (base RGBA u8, default white), `fadeTicks` (0 = no fade), `continuousRate` (particles PER SIMULATION TICK; 0 = burst-only — unbounded by design: the pool budget bounds the work, overflow drops)) + the constants `kParticlePoolMaxParticles` (2^16)/`kParticlePoolDefaultMaxParticles` (4096)/`kParticleEmitterMaxEmitters` (256)/`kParticleEmitterDefaultMaxEmitters` (32)/`kParticleMaxLifeTicks` (2^20)/`kParticleSampleDenominator` (2^24 — the Prng's 24-bit tap resolution) + `ParticleEmitterId` (dense from 1, 0 = the unused sentinel) + `ParticleStats` (the live/capacity gauges + the u64 spawnedTotal/droppedTotal counters — the DBG-008 feed); `create(options)` (`maxParticles` in [1, 2^16], `maxEmitters` in [1, 256], any u64 seed — validates (no log — the M2-SPRITE-01 create precedent), two pre-allocations: the pool (maxParticles × 40 B) + the emitter table (maxEmitters + 1 slots, index 0 unused) — the setup path, nothing allocates afterward); the public default ctor = the stopped state (`valid()` false, `addEmitter`/`burst` → `InvalidArgument` (no log), `update()` a no-op, `liveParticles()` empty, `stats()` zero) + move-only (O(1) pointer swap; moved-from = stopped — its Prng copy shares the stream position but never draws again); `addEmitter(def)` (dense id in registration order; validates in the documented order — origin → depth → vel_min → vel_max → vel_box → life_min → life_box → life_max → size_min → size_max → size_box → fade_ticks — first failure wins; a rejection leaves the registry unchanged + one rate-limited `particles/emitter_invalid` warn (fields `emitter` = the would-be id, `field`) — LOG-004; registry full → `BudgetExhausted` + `particles/emitters_exhausted` warn (field `capacity`); stopped → `InvalidArgument` (no log)); `burst(id, count)` (spawns NOW in the sim phase — the game's spawn policy; stopped or unknown id → `InvalidArgument` (no log — the M2-PAR-01 setUvOffset precedent), count 0 a no-op success; O(count)); `update()` (EXACTLY ONCE per completed sim tick — ARCH-002, the `TileMap::advanceAnimations` pattern — in-tick order: advance (live-array order: `age += 1`, `pos += vel` (one SimMath vector add — ADR 0002), `age >= life` kills via swap removal (the swapped-in particle — not yet advanced this tick — re-examined at the same index)) → emit (registration order, continuousRate each) → overflow report (at most ONE rate-limited `particles/pool_overflow` warn per tick, fields `dropped`/`live`/`capacity` — LOG-004; the logger 1s window is a second layer); O(live + Σrates), zero allocation, no logging on the happy path (LOG-003)); **lifetime semantics** — a particle emitted during tick T's update is visible for EXACTLY `life` renders (age 0..life-1, dies during tick T+life's update); a particle burst-spawned before tick T's update is advanced by that same tick (visible for life − 1 renders — the documented per-tick contract); **determinism (ARCH-010, ADR 0002)** — the state after N updates is a pure function of (seed, emitter definitions, operation sequence): each SUCCESSFUL spawn consumes exactly FOUR Prng draws in a fixed order (vx, vy, life, size) — each uniform scalar `lerp(min, max, u / 2^24)` (the Prng's 24-bit tap resolution, one documented rounding per backend), `life` an integer draw; a DROPPED spawn consumes NO draws (the pool check precedes the draws — a drop never perturbs the stream); fpx16_16 bit-identical across all builds/platforms/ISAs, fp32_pinned same-build/same-platform (the detcheck matrix owns cross-target claims); the Prng state is exposed (`prngSeed()`/`prngStatePart1()`/`prngStatePart2()`) for the World `stateHash` / replay identity (the M1-DET-03 pattern); **pool budget (FR-2.7, PERF-003/008)** — overflow = DROP (counted in `droppedTotal`, one warn per tick window) — never grows the pool, never throws, never mutates live state; the `stats()` feed is the budget's observability (DBG-008); **threading (CORE-009, CONC-001)** — one owner (the sim thread); the render pass reads `liveParticles()` (a non-owning `std::span` of the compact live prefix — spawn order with swap removal) read-only after the sim phase (the M2-GL-02 cull/batch stage, ARCH-009); **tests** — NEW `tests/laige-sim/particles_tests.cpp` (new CTest entry `particles` = the step's Verify command; 17 tests / 10 suites, both backends, no GL — runs in every tree): `ParticlesCreate` (the create domain edges (maxParticles 0 / 2^16 / 2^16+1, maxEmitters 0 / 256 / 257 — first failure wins, no log on rejection), the stopped-state matrix, move-stops-source (no log)), `ParticlesEmitter` (dense ids, the validation matrix — every rejection case with the pinned warn fields (first failure wins, incl. the fp32 NaN cases + the fpx box cases), state-unchanged-on-rejection, the registry `BudgetExhausted` with the pinned `capacity` field, the no-log happy path), `ParticlesBurst` (a degenerate def's EXACT particle fields pinned (Q16.16 raws / dyadic floats — origin/depth/vel/life/size/tint/fade), count 0 no-op, unknown-id/stopped `InvalidArgument` no log, the pool drop with the pinned `dropped`/`live`/`capacity` fields — one warn), `ParticlesUpdate` (hand-computed per-tick advance goldens both backends (vel (0.5, −0.25) from (1,2): Q16.16 raw x = 65536 + 32768k, y = 131072 − 16384k; float 1.5/2.0/2.5/3.0 & 1.75/1.5/1.25/1.0), death at EXACTLY age == life (5 renders for life 5), the swap-removal live order), `ParticlesContinuous` (the rate + the first two spawns' (vel, life, size) cross-checked against an independent `Prng` oracle — the 4-draw contract — + the pool-full one-warn-per-tick pin), `ParticlesDeterminism` (50 ticks + a burst(2,5) every 10th tick on a capacity-8 pool (drops occur): same seed → bit-identical live set (every field, both backends) + the machine-greppable `particles-determinism … fnv1a=0x…` state-hash line (FNV-1a 64, the docs/testing.md §4 KAT convention), a different seed diverges, an independent `Prng` advanced by 4 × spawnedTotal draws lands on the system's stream state (the no-draws-on-drop contract), `EXPECT_GT(droppedTotal, 0)` pinning the exercised drop path), `ParticlesFade` (the EXACT integer fade table: life 8/fade 4/tint.a 255 → age 0..7 alpha [255,255,255,255,255,191,127,63], tint.a 200 → 150/100/50 at age 5/6/7, fadeTicks 0 constant — direct `fadeAlpha` + through the system), `ParticlesPoolExhaustion` (the EXACT per-tick table — capacity 3, rate 2, life 4: live [2,3,3,3,3,3,3,3,3,3], droppedTotal [0,1,3,5,5,6,8,10,10,11], cumulative warns [0,1,2,3,3,4,5,6,6,7] — one per tick where drops occur), `ParticlesStats` (the exact `ParticleStats` feed: {4 live, 4 capacity, 8 spawned, 2 dropped} after 5 ticks), `ParticlesZeroAlloc` (500 ticks × 6 spawns + a periodic burst under the owner-thread allocation watch — 0 heap allocations + the machine-greppable `particles-zeroalloc ticks=500 allocs=0` line; the steady-state counters pinned); **docs** — NEW `docs/api/particles.md` (the full contract: the API table, the per-tick contract, the pool budget, the determinism scope, the color fade, the failure table (first failure wins), ownership/lifetime/threading, the DOC-004 Performance section, the performant example + the misuse warnings), `docs/README.md` (the API index entry + the laige-sim doc list), `src/laige-sim/README.md` (the module status paragraph), `docs/concepts/coordinates.md` (NEW §4.11 + the §5 conversion row "Particle state → sprite items" (Planned, M2-PART-02) + the Related link); **API surface** — `laige-api.json` regenerated LAST (1342 → 1410 symbols, 40 → 41 headers); **budget** — no standalone `budgets.json` entry (the count stays 16 — the `BudgetHarnessTable.LoadsTheRepoBudgetsFile` pin): the particle→sprite budget is measured in M2-PART-02 against the composite 50k render-CPU budget (PRD §8.1); **compat** — additive only (no existing symbol's signature or meaning changed); **local verification** — all six local trees warning-clean + full `ctest` green: build 115/115, build-clang 115/115, build-release 104/104, build-shared 115/115, build-asan 112/112, build-tsan 112/112 (the prior counts +1 each — the new `particles` entry); `ctest -R particles` green (17/17, both backends); `api-real-tree`/`api-check-fresh` (2/2), `tools/laige-include-lint` (70 source files), and `tools/laige-determinism-lint` (29 sim source files, 0 violations) green after the final `laige-api.json` regeneration; Progress Board M2 20/33, total 66/194 | | 2026-10-07 | M2-PART-02 | `—` / PR #83 | Particle rendering through the batcher (FR-2.7 — "particles render as batched sprites"; M2-PART-02 scope, nothing else): **API** — NEW header-only `src/laige-render/include/laige/render/particle_render.h` (`laige::render`, public, additive; templated over the SimMath backends — the `presentation.h` pattern): `particleDepthToStepHeight(depth) → int32` (the sim depth value → the M2-ISO-01 integer step height: clamp to ±`kIsoDepthMaxStepHeight` (2047) FIRST — per backend, SimMath has no ordering: fpx raw integer compares, fp32 IEEE compares, NaN falls through to +2047 (presentation-only, ARCH-009) — then round nearest ties-to-even (fpx `fpx16_16::toInt32`, fp32 `std::nearbyint` in the pinned rounding mode — the two backends agree on dyadic depths; NOT `llround`, which would diverge on 0.5)) + `ParticleDeclareOptions` (the emitter set's shared render attributes: `atlasId`/`materialId`/`blend` (default `BlendMode::Additive` — the particle convention)/`uv` (default the full atlas)/`layer` (default `kIsoDepthGroundLayer` = 0)) + `kTintChannelDivisor` (255.0f) + `declareParticles(batcher, system, options) → Status` (the O(live) conversion pass: every live particle — live-array order, the deterministic tie-break (RENDER-003) — becomes one `SpriteItem`: the world position at the RENDER-006 boundary (one documented rounding per component per backend), the engine-owned `depthKey` = `isoDepthKey(p.pos, particleDepthToStepHeight(p.depth), options.layer)` (G-R11; `depthOverride` false), the square `scale (size, size)`, the tint (u8→float /255 RGB + the M2-PART-01 exact-u32 `fadeAlpha` /255), the shared `uv`/`atlasId`/`materialId`/`blend`, `frameIndex`/`rotation` 0 (no per-particle animation/rotation in this step); first failed add fails the call with the batcher's error — stopped batcher → `BudgetExhausted` (an empty system still succeeds: no adds attempted), closed window → `InvalidArgument`, frame-budget overflow → the batcher's own drop-oldest + warn policy (the conversion succeeds); O(live), no allocation, no logging, no GL); **build** — `laige-render` links `laige-sim` PUBLIC (the module stack's legal downward direction, PRD §10.1 — render MAY include sim public headers; the M2-GL-02 "no render→sim edge" note covers the frame-pipeline handoff, which stays an opaque pointer); **tests** — NEW ctest entry `particle_render` (`tests/laige-render/particle_render_tests.cpp`, 9 suites, both backends, no GL): the per-particle declaration goldens against the M2-ISO-01 oracle + the hand-computed dyadic key goldens (0x801FFFE0/0x80200000×3/0x80200020/0x80200030 — awk-verified before pinning), the depth conversion (sub-unit ties-to-even 0.5→0, 1.5→2; ±3000→±2047 saturation; the (key, live-order) in-group ordering with the A/B/F tie), the exact fade through the declaration (life 8/fade 4 → alphas 255×5/191/127/63), the multi-emitter-set group count (3 sets → 3 groups in ascending (atlas, material, blend) order — one draw call per set, RENDER-001), the failure paths, the fixed-seed determinism (identical declared (key, pos) sequence + the machine-greppable `particle-render-determinism` FNV-1a hash line; a different seed diverges), the 1 000-frame 10k-particle zero-allocation declare loop (`particle-render-zeroalloc ... allocs=0`, the alloc-watch gate), and the budget suite (below); **budget** — NEW `budgets.json` entry `particle_render_10k` (mean, ms, target 2.0, step-level — the `depth_sort_10k` precedent: no PRD revision): the 10k-particle conversion pass ONLY (the batcher's `build`/sort is the separate `depth_sort_10k` budget — `beginFrame`/`build` outside the measured window, the frame protocol keeps the phases apart), 100 warm-up + 3 000 measured declare passes, both backends (the gate is backend-complete, ADR 0002); gated on the Linux non-instrumented trees (`LAIGE_PARTICLE_RENDER_BUDGET` + `LAIGE_PARTICLE_RENDER_BUILD_TYPE`), ungated elsewhere (the sanitizer trees run the workload for its leak/race value); `measured` = **1.07798** (the worse of the two backends — fpx16_16 1.07798 / fp32_pinned 0.996543 — canonical Debug tree, n=3000) — 1.86× inside the 2.0 ms gate; **NEW baseline** `docs/benchmarks/baselines/m2-particle-render.md` (the tenth baseline, verbatim reports + cross-compiler clang -O0 run); budgets.json entry count 16 → 17 (the `BudgetHarnessTable.LoadsTheRepoBudgetsFile` pin updated); **docs** — NEW `docs/api/particle_render.md` (the full contract + the DOC-004 Performance section); `docs/api/particles.md` (the render half now implemented — link + the render-phase example + Related), `docs/concepts/coordinates.md` (§4.11 narrative + the §5 conversion row Planned → **Shipped** + Related), `docs/README.md` (the API index), `src/laige-render/README.md` (the M2-PART-02 status paragraph); **build fix** — the system clang 22.1.8 → 23.1.1 upgrade surfaced `-Werror,-Wunused-but-set-global` on pre-existing sim test files: removed the dead `MemorySink* sink` globals in `tests/laige-sim/game_loop_tests.cpp` + `presentation_tests.cpp` + `system_timing_tests.cpp` (written, never read — the tests use `installCaptureSink()`'s return value) and `LAIGE_ALLOC_COUNTER`-gated the `schReadPosSum` read-back in `tests/laige-sim/scheduler_tests.cpp` (its only read site is the zero-alloc window test, which compiles out on the sanitizer clang trees); **API surface** — `laige-api.json` regenerated LAST (1410 → 1419 symbols, 41 → 42 headers); **compat** — additive only (no existing symbol's signature or meaning changed); **local verification** — all six local trees warning-clean + full `ctest` green (build 116/116, build-clang 116/116, build-release 105/105, build-shared 116/116, build-asan 113/113, build-tsan 113/113 — the prior counts +1 each, the new `particle_render` entry; the counts above are the re-run after the sink fix); `ctest -R particle_render` green (9/9, both backends); `api-real-tree`/`api-check-fresh` (2/2), `tools/laige-include-lint` (71 source files), and `tools/laige-determinism-lint` (29 sim source files, 0 violations) green after the final `laige-api.json` regeneration; Progress Board M2 21/33, total 67/194 | | 2026-10-08 | M0-CI-01 | `—` | **CI follow-up: the PR lane is Windows/macOS only** — the Linux P0 jobs (`linux-gcc`, `linux-clang`, `linux-asan`, `linux-tsan`) are removed from `ci-pull.yml`: Linux builds/tests are verified locally on the developer machine (the canonical trees of docs/getting-started/building.md, incl. the `LAIGE_ASAN=ON` / `LAIGE_TSAN=ON` instrumented trees), so the PR-lane label selector is now `ci:windows` / `ci:macos` only (no label = the platform-independent tooling jobs only; the former `ci:linux` label is a no-op). The merge lane (`ci.yml`) is unchanged — every merge to master still runs the full 11-job matrix (all P0 OSes, both sanitizer lanes, all tooling jobs), the "all per merge" half of the PRD §14 cadence. No engine code change — workflow headers + this log line only. | +| 2026-10-08 | M2-TEXT-01 | `—` / PR (open) | Font rasterization — bitmap (FR-2.8 bitmap P0; M2-TEXT-01 scope, nothing else): **vendoring** — `stb_truetype.h` pinned from nothings/stb commit `2c980bb…` (2026-08-01 — stb has no release tags; the pinned commit is the API reference: no `stbtt_GetFontOffsetForData`, no per-codepoint convenience wrappers — the glyph-index + metrics surface is the API), tree-hash-pinned in `deps.lock` (5 vendored deps; ADR 0009 — DEP-003 justification, FreeType / hand-rolled / baked-atlas alternatives all rejected); **API** — NEW `laige::render::GlyphAtlas` (public header `include/laige/render/font.h`, implementation `font.cpp`; the `laige-stb` static target compiles the vendor header in one impl TU under the plain-compiler policy — DEP-005): `GlyphAtlas::create(fontBytes, Options)` — validate options first (atlas dims [1, 4096], fontSize [1, 1024], range ≤ 8192 codes, first ≤ last ≤ 0x10FFFF — first failure wins, no log), then the untrusted-font boundary (engine-side header + table-directory guard BEFORE any stb call — stbtt's directory scan is not bounds-checked — then `GetFontOffsetForIndex`/`InitFont`; failure → `MalformedInput` + one structured Error `font/font_invalid`), then rasterize every codepoint of the range into the fixed 8-bit alpha atlas (deterministic shelf packing, ascending codepoint, cells are exactly the ink bitmap, empty glyphs take no space) — a glyph wider/taller than the atlas, or a full shelf → `BudgetExhausted` + one Error `font/atlas_full`; success → one Info `font/atlas_created`; move-only, stopped default state (nothing owned, `glyph` → nullptr); `GlyphMetrics` (advance, bearingX/Y, width/height, atlasX/Y — all px at 1x, `lineHeight() == fontSize()` by the stbtt pixel-height convention, advance = lround(advanceUnits × scale)); `glyph(code)` total + O(1) + zero-alloc + never logs: in-range → the slot (unknown codepoints → the font's `.notdef`), out-of-range → the U+0020 space slot (else the zero metric when the range excludes the space); **tests** — `tests/laige-render` CTest entry `font` (the step's Verify command; pure engine data, no GL — runs in every local tree + CI; `LAIGE_TEST_FONT_PATH` env var on the entry + the unfiltered entry + the TSan block): the validation matrix (no log), the untrusted-font boundary (empty / short / directory-cut / non-font / degenerate vertical metrics — exactly one structured Error each), the stopped state, the capacity guard (one Error), the introspection + one-Info contract, the move semantics, the metric goldens MEASURED against the committed test font (`tests/laige-render/assets/vera.ttf` — Bitstream Vera Sans, OFL 1.1; the assets/ README documents provenance + license), the `.notdef` fallback (both C1 probes → identical shape, separate cells), the out-of-range fallback (space slot / zero metric), the atlas invariants (every cell inside the fixed atlas — caught a real packing bug: wrapped cells' metrics pointed at the stale pre-wrap cursor), the deterministic-atlas contract (same font + options → identical bytes + metrics; the machine-greppable `font-atlas-determinism` fnv1a line — NO pinned cross-platform hash: presentation-only float, ARCH-009, the scope is in-process/same-build, unlike the M2-PROJ-01/ISO-03 transform scope), the 1000-lookup zero-allocation window; **budget** — no `budgets.json` entry (the atlas is built once at set-up, not per frame — the per-frame text cost lands with M2-TEXT-02, part of the composite 50k render-CPU budget, M2-PERF-01; the entry count stays 17); **docs** (DOC-006/007) — ADR 0009 (`docs/decisions/` + index), `docs/api/font.md` (the full contract incl. the DOC-004 Performance section), `deps/README.md` (the stb row + the missing GLM row fixed), `docs/README.md` API index, `src/laige-render/README.md` status, `tests/laige-render/assets/README.md`; **local verification** — the canonical `build` tree warning-clean, `ctest -R font` green (20/20) + full ctest 117/117 (prior 116 + the new `font` entry); `tools/laige-include-lint` OK (74 files, 5/10 vendored deps, 16 allowed vendored edges), `tools/laige-determinism-lint` OK; `laige-api.json` regenerated LAST (1419 → 1462 symbols, 42 → 43 headers) + `api-real-tree` green; the five remaining trees verified after the change (prior counts + 1 each); Progress Board M2 22/33 (total 68/194) | --- diff --git a/src/laige-render/CMakeLists.txt b/src/laige-render/CMakeLists.txt index f3bbe60..8f3895e 100644 --- a/src/laige-render/CMakeLists.txt +++ b/src/laige-render/CMakeLists.txt @@ -56,6 +56,17 @@ add_library(laige-glad STATIC ${CMAKE_SOURCE_DIR}/deps/glad/src/gl.c) target_include_directories(laige-glad PRIVATE ${CMAKE_SOURCE_DIR}/deps/glad/include) +# stb_truetype (M2-TEXT-01, ADR 0009): the single-header font rasterizer, +# pinned in deps/stb (deps.lock). The implementation compiles ONCE in +# this target under the plain compiler policy (pinned vendor code, +# DEP-005 — the laige-glad precedent); the engine boundary is +# font.cpp, which includes the vendor header's declarations and links +# this target (PRIVATE — the public header names no stb type, CPP-010, +# DEP-004). +add_library(laige-stb STATIC stb_truetype_impl.cpp) +target_include_directories(laige-stb PRIVATE + ${CMAKE_SOURCE_DIR}/deps/stb) + # M2-CAM-01 adds camera.cpp (the 3D camera core: position/look-at, # ortho/perspective with clamped zoom, the rectangular bounds # constraint, the smooth follow, the bounded decaying shake — the @@ -78,9 +89,13 @@ target_include_directories(laige-glad PRIVATE # — iso default, side_view, top_down, free_cinematic — and the # screen<->world transforms: worldToScreen / screenToWorldRay / # screenToWorld, the FR-2.11 picking base; pure value math over the -# M2-GL-03 / M2-CAM-01 matrices, no GL calls). +# M2-GL-03 / M2-CAM-01 matrices, no GL calls). M2-TEXT-01 adds +# font.cpp (the bitmap glyph atlas: the caller's font bytes + a +# configured glyph range rasterized ONCE at scene set-up into a +# fixed-size 8-bit alpha atlas + per-glyph metrics — the FR-2.8 P0 +# bitmap path, no GL calls; the vendor boundary is laige-stb, above). set(LAIGE_RENDER_SOURCES gl_context.cpp frame_pipeline.cpp matrices.cpp - camera.cpp iso_camera.cpp projection.cpp sprite_renderer.cpp) + camera.cpp iso_camera.cpp projection.cpp sprite_renderer.cpp font.cpp) if(LAIGE_BUILD_SHARED) add_library(laige-render SHARED ${LAIGE_RENDER_SOURCES}) @@ -112,6 +127,12 @@ target_link_libraries(laige-render PRIVATE glfw laige-glad) # headers), likewise PRIVATE. target_include_directories(laige-render PRIVATE ${CMAKE_SOURCE_DIR}/deps/glad/include) +# M2-TEXT-01: the stb_truetype boundary — font.cpp uses the vendor +# header's declarations (the implementation lives in laige-stb); public +# headers never name stb types (CPP-010, DEP-004, ADR 0009). +target_link_libraries(laige-render PRIVATE laige-stb) +target_include_directories(laige-render PRIVATE + ${CMAKE_SOURCE_DIR}/deps/stb) # GLM (M2-GL-03, ADR 0008): unlike GLFW/GLAD (opaque native resources # behind the pimpl), GLM is a pure value-type math library and is part diff --git a/src/laige-render/README.md b/src/laige-render/README.md index 7e60cb8..d33be81 100644 --- a/src/laige-render/README.md +++ b/src/laige-render/README.md @@ -563,4 +563,49 @@ the batcher's sort is the separate `depth_sort_10k` budget): recorded `docs/benchmarks/baselines/m2-particle-render.md` baseline, the tenth). -The remaining M2 steps (text/UI, M2-PERF-01) land in later steps. +M2-TEXT-01 landed the bitmap font atlas — the bitmap half of +FR-2.8: `laige::render::GlyphAtlas` (public header +`include/laige/render/font.h`, implementation `font.cpp`) builds the +configured font + glyph set ONCE at scene set-up — +`GlyphAtlas::create(fontBytes, Options)` (default Options: 1024² +atlas, 16 px font size, the Latin-1 range 32..255) validates the +options (the documented order — first failure wins, no log), +rejects untrusted font bytes (the header + table directory guard — +stb's directory scan is not bounds-checked, so the engine guards it +before any stb call — SCALE-004), then rasterizes every codepoint +into the fixed 8-bit alpha atlas (deterministic shelf packing, +cells are exactly the ink bitmap, empty glyphs take no space) and +returns the move-only atlas + the per-codepoint `GlyphMetrics` +(advance, bearingX/Y, width/height — all px at 1x, the scale factor +documented; `lineHeight() == fontSize()` by the stbtt pixel-height +convention). The lookup path is `glyph(code)` — total (null only on +the stopped atlas), O(1), zero-allocation, never logs: in-range +codes read their slot, out-of-range codes fall back to the U+0020 +space slot (or the zero metric when the range excludes the space), +in-range codes the font lacks map to the font's .notdef. The vendor +boundary is the `laige-stb` static library — the single +`stb_truetype_impl.cpp` TU that compiles the vendored header (ADR +0009, the plain-compiler policy of the vendor impl TUs — DEP-005); +the engine TU (`font.cpp`) never sees the stb internals beyond the +narrow include. No GL calls anywhere; the atlas is presentation +state (ARCH-009) and lands in the M2-TEXT-02 UI pass as a +white-on-alpha RGBA8 upload through the M2-SPRITE-02 `bindAtlas` +path. API contract in +[docs/api/font.md](../docs/api/font.md), tests under +[tests/laige-render](../tests/laige-render) (CTest entry `font` — +pure engine data, no GL environment required: the validation matrix, +the untrusted-font boundary (truncated / non-font / degenerate +vertical-metric bytes), the stopped state, the capacity guard, the +metric goldens measured +against the committed Vera test font +(`tests/laige-render/assets/vera.ttf`), the deterministic-atlas +contract (same font + options → identical bytes, the +machine-greppable fingerprint line — no pinned cross-platform hash, +the presentation-float scope of ARCH-009), the fallback matrix, the +atlas invariants, and the 1000-lookup zero-allocation window). No +standalone `budgets.json` entry: the atlas is built once at set-up, +not per frame — the per-frame text cost lands with M2-TEXT-02 +(part of the composite 50k render-CPU budget, M2-PERF-01). + +The remaining M2 steps (text items/UI, M2-SCENE-01, M2-PERF-01) land +in later steps. diff --git a/src/laige-render/font.cpp b/src/laige-render/font.cpp new file mode 100644 index 0000000..3292f73 --- /dev/null +++ b/src/laige-render/font.cpp @@ -0,0 +1,263 @@ +// laige-render bitmap font atlas implementation (M2-TEXT-01). +// +// The engine boundary of the vendored stb_truetype rasterizer (ADR +// 0009): this file uses the vendor header's DECLARATIONS only (the +// implementation is compiled once in laige-stb, plain compiler policy), +// and the public header (font.h) names no stb type (CPP-010, DEP-004). + +#include "laige/render/font.h" + +#include +#include +#include +#include +#include + +#include "laige/logging.h" +#include "stb_truetype.h" // declarations only (impl: laige-stb target) + +namespace laige::render { +namespace { + +// The TrueType/OpenType header + table-directory guard (the untrusted- +// input boundary, SCALE-004): stb reads the font header and scans the +// table directory WITHOUT bounds checks (its buf-based table parsing is +// bounds-checked, the directory scan is not — verified against the +// pinned header), so the engine requires the header (12 bytes) and the +// FULL table directory to be present before any stb call. A truncated +// or non-font file is rejected here, never read past. +// Returns false (not a parsable font header) when the guard fails. +bool fontDirectoryPresent(std::span font) noexcept { + constexpr std::size_t kHeaderBytes = 12; // 4 version + 4 count + 4 offset + if (font.size() < kHeaderBytes) { + return false; + } + const std::uint32_t numTables = + (static_cast(font[4]) << 8) | + static_cast(font[5]); + return kHeaderBytes + 16 * numTables <= font.size(); +} + +// One rasterized glyph bitmap. Owns the stbtt-malloc'd buffer — the +// C-library allocation is encapsulated here (CPP-005). +struct GlyphBitmap { + std::uint8_t* data = nullptr; + std::int32_t width = 0; + std::int32_t height = 0; + ~GlyphBitmap() { + if (data != nullptr) { + std::free(data); + } + } +}; + +} // namespace + +laige::Result GlyphAtlas::create( + std::span font, Options options) noexcept { + // --- 1. Options validation (the documented order, first failure wins; + // no log — the M2-SPRITE-01 create precedent) ------------------------- + if (options.atlasWidth < 1 || options.atlasWidth > kFontMaxAtlasDimension || + options.atlasHeight < 1 || options.atlasHeight > kFontMaxAtlasDimension || + options.fontSize < 1 || options.fontSize > kFontMaxFontSize || + options.glyphFirst > options.glyphLast || + options.glyphLast > kFontMaxGlyphCode || + options.glyphLast - options.glyphFirst + 1 > kFontMaxGlyphCount) { + return laige::Result::failure( + laige::ErrorCode::InvalidArgument); + } + + // --- 2. The font bytes (untrusted input, SCALE-004) ------------------- + if (!fontDirectoryPresent(font)) { + LAIGE_LOG_ERROR("font", "font_invalid", + "The configured font file is not a parsable TTF/OTF " + "font (truncated or non-font bytes)", + laige::log::field("bytes", font.size())); + return laige::Result::failure( + laige::ErrorCode::MalformedInput); + } + stbtt_fontinfo stbFont; + // The directory guard above makes the scan reads in-bounds; the offset + // for a plain font is 0 (a TTC's first font is what index 0 names). + const int offset = stbtt_GetFontOffsetForIndex(font.data(), 0); + if (offset < 0 || !stbtt_InitFont(&stbFont, font.data(), offset)) { + LAIGE_LOG_ERROR("font", "font_invalid", + "The configured font file failed TTF/OTF parsing " + "(missing required tables or corrupt table data)", + laige::log::field("bytes", font.size())); + return laige::Result::failure( + laige::ErrorCode::MalformedInput); + } + + // --- 3. The fixed-size atlas + per-codepoint slots --------------------- + GlyphAtlas atlas; + atlas.atlasWidth_ = options.atlasWidth; + atlas.atlasHeight_ = options.atlasHeight; + atlas.fontSize_ = options.fontSize; + atlas.glyphFirst_ = options.glyphFirst; + atlas.glyphLast_ = options.glyphLast; + atlas.atlas_.assign( + static_cast(options.atlasWidth) * + static_cast(options.atlasHeight), + 0); + const std::size_t slotCount = + static_cast(options.glyphLast - options.glyphFirst + 1); + atlas.slots_.reserve(slotCount); // the set-up path's only allocations + + const float scale = + stbtt_ScaleForPixelHeight(&stbFont, static_cast(options.fontSize)); + // The degenerate-metric guard (SCALE-004): the pixel-height scale + // (px per font unit = fontSize / (hhea ascent − hhea descent)) must + // be finite and in the int domain, so stbtt's float→int box rounding + // and the lround'd advance (advanceUnits ≤ 65535 × scale, box ≤ + // 65534 × scale — both < 2^31 when scale ≤ 2^15) stay in their int + // domains. The reachable max is kFontMaxFontSize / 1 = 1024 (the + // 2^15 bound is the explicit int-domain ceiling); scale ≤ 0 or inf + // means a font with zero/inverted vertical metrics — malformed. + constexpr float kMaxPixelScale = 32768.0f; // 2^15, the int-domain bound + if (!std::isfinite(scale) || scale <= 0.0f || scale > kMaxPixelScale) { + LAIGE_LOG_ERROR("font", "font_invalid", + "The font's vertical metrics are degenerate (the " + "pixel-height scale is not a finite value in the " + "documented domain)", + laige::log::field("bytes", font.size())); + return laige::Result::failure( + laige::ErrorCode::MalformedInput); + } + + // The deterministic shelf packing (font.h preamble): ascending + // codepoint order, one shelf row at a time, cells exactly the ink + // bitmaps. + std::uint32_t cursorX = 0; + std::uint32_t cursorY = 0; + std::uint32_t rowHeight = 0; + for (std::uint32_t code = options.glyphFirst; code <= options.glyphLast; + ++code) { + const int glyphIndex = stbtt_FindGlyphIndex(&stbFont, static_cast(code)); + int x0 = 0; + int y0 = 0; + int x1 = 0; + int y1 = 0; + stbtt_GetGlyphBitmapBox(&stbFont, glyphIndex, scale, scale, &x0, &y0, &x1, + &y1); + const std::int32_t w = static_cast(x1 - x0); + const std::int32_t h = static_cast(y1 - y0); + + // The capacity check BEFORE the bitmap allocation: the cell must fit + // the fixed atlas (a single cell wider/taller than the atlas can + // never pack), and it bounds stb's w * h allocation to + // atlasWidth * atlasHeight <= 2^24 bytes (no int overflow, no + // unbounded malloc — the malicious-font guard, SCALE-004). + if (w > 0 && (w > static_cast(options.atlasWidth) || + h > static_cast(options.atlasHeight))) { + LAIGE_LOG_ERROR("font", "atlas_full", + "A glyph's bitmap does not fit the fixed glyph atlas " + "(grow the atlas or shrink the font size)", + laige::log::field("code", code), + laige::log::field("width", w), + laige::log::field("height", h), + laige::log::field("atlas_width", options.atlasWidth), + laige::log::field("atlas_height", options.atlasHeight)); + return laige::Result::failure( + laige::ErrorCode::BudgetExhausted); + } + + // The pen advance (unscaled font units; the LSB is not a metric + // here — the bearing comes from the ink box's x0, the bitmap's true + // left edge). + int advanceUnits = 0; + stbtt_GetGlyphHMetrics(&stbFont, glyphIndex, &advanceUnits, nullptr); + + GlyphMetrics metrics; + metrics.bearingX = x0; // the bitmap's left edge from the pen (right +) + metrics.bearingY = -y0; // the bitmap's top edge above the baseline (up +) + metrics.width = w; + metrics.height = h; + metrics.advance = + static_cast(std::lround(advanceUnits * scale)); + + if (w > 0) { + // The shelf packing: wrap the row when the cell does not fit. + if (cursorX + static_cast(w) > options.atlasWidth) { + cursorX = 0; + cursorY += rowHeight; + rowHeight = 0; + } + if (cursorY + static_cast(h) > options.atlasHeight) { + LAIGE_LOG_ERROR("font", "atlas_full", + "The glyph atlas is full (the configured glyph range " + "does not fit the fixed atlas; grow the atlas or " + "shrink the font size)", + laige::log::field("code", code), + laige::log::field("atlas_width", options.atlasWidth), + laige::log::field("atlas_height", options.atlasHeight)); + return laige::Result::failure( + laige::ErrorCode::BudgetExhausted); + } + } + // The cell origin is the cursor AFTER any row wrap (a wrapped cell + // starts the new row, not at the stale end of the old one). + metrics.atlasX = cursorX; + metrics.atlasY = cursorY; + + if (w > 0) { + if (h > 0) { + GlyphBitmap bitmap; + bitmap.width = w; + bitmap.height = h; + bitmap.data = stbtt_GetGlyphBitmap(&stbFont, scale, scale, glyphIndex, + &bitmap.width, &bitmap.height, + nullptr, nullptr); + if (bitmap.data == nullptr) { + // Unreachable for a validated (w, h): STBTT_malloc failure is + // the only null path, and w * h <= 2^24 bytes. + LAIGE_LOG_ERROR("font", "rasterize_failed", + "Glyph bitmap rasterization failed (allocation " + "failure in the font rasterizer)", + laige::log::field("code", code)); + return laige::Result::failure( + laige::ErrorCode::MalformedInput); + } + // The verbatim copy (8-bit alpha rows, the stbtt row-major layout). + for (std::int32_t row = 0; row < h; ++row) { + std::uint8_t* dst = + atlas.atlas_.data() + + static_cast(cursorY + static_cast(row)) * + static_cast(options.atlasWidth) + + cursorX; + std::copy_n(bitmap.data + static_cast(row) * w, w, dst); + } + cursorX += static_cast(w); + if (h > static_cast(rowHeight)) { + rowHeight = static_cast(h); + } + } + } + atlas.slots_.push_back(metrics); + } + + LAIGE_LOG_INFO("font", "atlas_created", + "The bitmap glyph atlas was built at scene set-up", + laige::log::field("atlas_width", options.atlasWidth), + laige::log::field("atlas_height", options.atlasHeight), + laige::log::field("font_size", options.fontSize), + laige::log::field("glyphs", slotCount)); + return laige::Result::success(std::move(atlas)); +} + +const GlyphMetrics* GlyphAtlas::glyph(std::uint32_t code) const noexcept { + if (!valid()) { + return nullptr; + } + if (code >= glyphFirst_ && code <= glyphLast_) { + return &slots_[static_cast(code - glyphFirst_)]; + } + // The documented fallback (font.h preamble): the U+0020 slot when the + // configured range includes it, else the zero metric. + if (kFontFallbackCode >= glyphFirst_ && kFontFallbackCode <= glyphLast_) { + return &slots_[static_cast(kFontFallbackCode - glyphFirst_)]; + } + return &kFontEmptyGlyphMetrics; +} + +} // namespace laige::render diff --git a/src/laige-render/include/laige/render/font.h b/src/laige-render/include/laige/render/font.h new file mode 100644 index 0000000..19fc98a --- /dev/null +++ b/src/laige-render/include/laige/render/font.h @@ -0,0 +1,279 @@ +// laige-render bitmap font atlas (M2-TEXT-01): the bitmap half of FR-2.8 +// — "Text rendering ... bitmap (P0); SDF (P1)". +// +// FR-2.8: "Text rendering: ... bitmap font atlas (P0), SDF (P1), ..." +// This step ships the P0 bitmap path: the caller's TTF/OTF font bytes + +// a configured glyph range are rasterized ONCE, at scene set-up, into a +// fixed-size 8-bit alpha glyph atlas + per-glyph metrics (advance, +// bearing, line height). There is NO runtime re-rasterization: after +// `create`, `glyph(code)` is a pure table lookup. The SDF path (P1) +// lands in M2-TEXT-03 on top of the same vendored rasterizer (ADR +// 0009); the text widget / layout pass lands in M2-TEXT-02. +// +// GlyphAtlas The configured glyph atlas (create + lookup) +// GlyphMetrics Per-glyph metrics + atlas cell origin +// kFont* The named constants (CORE-005) +// +// --------------------------------------------------------------------------- +// The model (documented units) +// --------------------------------------------------------------------------- +// +// All metric values are PIXELS AT 1x — i.e. at the atlas's configured +// `fontSize` (the font's pixel height, the stbtt pixel-height +// convention: the font's ascent + descent scaled to exactly that +// height). To render at an integer scale s, multiply every metric by +// s (exact for integer s); the atlas bitmap itself is then drawn at +// s× its texel size (the M2-TEXT-02/M2-SPRITE-02 sprite `scale`). +// +// `GlyphAtlas::create(font, options)`: +// +// 1. Validates `options` (the documented order below, first failure +// wins — all `InvalidArgument`, no log); +// 2. Validates the FONT BYTES at the untrusted-input boundary +// (SCALE-004): a non-font / truncated / corrupt file → +// `MalformedInput` + one structured Error `font/font_invalid` +// (CORE-008 — never a crash, never a silent fallback); +// 3. Rasterizes every codepoint in `[glyphFirst, glyphLast]` into the +// fixed `atlasWidth × atlasHeight` 8-bit alpha atlas with the +// deterministic shelf packing below (a glyph that does not fit → +// `BudgetExhausted` + one structured Error `font/atlas_full` — +// the atlas is fixed-size by contract; grow the atlas, not the +// font); +// 4. On success: one Info `font/atlas_created` (the set-up path is +// low-volume; the lookup path logs nothing). +// +// The font bytes are a NON-OWNING span: the caller owns them (the game's +// asset pipeline — the M3 asset system); they are read only during +// `create` and may be freed immediately after (the atlas owns a copy of +// the bitmap, not the font). +// +// --------------------------------------------------------------------------- +// The atlas layout (deterministic shelf packing) +// --------------------------------------------------------------------------- +// +// The atlas is `atlasWidth × atlasHeight` texels of 8-bit alpha (0 = +// transparent). Codepoints are laid out in ASCENDING order, one shelf +// row at a time: the cursor starts at (0, 0); a glyph's cell is placed +// at the cursor; the cursor advances right by the cell's width; when +// the cell would not fit on the row it wraps to the next row (the +// cursor's y advances by the row's max cell height). A cell is EXACTLY +// the glyph's ink bitmap (no padding — stbtt's rasterization is +// clipped to the cell, so no glyph can bleed into a neighbor; the +// M2-SPRITE-02 `GL_NEAREST` "texel = floor(u·W)" contract applies). +// Empty glyphs (zero-width/height ink — e.g. the space) occupy NO cell +// space. The packing is a pure function of (font bytes, options): +// same input → bit-identical atlas bytes (the determinism test). +// +// `GlyphMetrics.atlasX/atlasY` is the cell's top-left texel; the glyph's +// UV rect for the M2-SPRITE-02 upload is +// `(atlasX/W, atlasY/H, (atlasX+width)/W, (atlasY+height)/H)` (the +// M2-SPRITE-03 v-axis convention: v = 0 = first uploaded texel row). +// +// --------------------------------------------------------------------------- +// The metrics (px at 1x) +// --------------------------------------------------------------------------- +// +// advance the pen advance after drawing the glyph (positive = +// right; a negative advance is stored as-is — RTL/quirk +// fonts are out of scope, but the field is total). +// bearingX the horizontal offset of the bitmap's LEFT edge from the +// pen (positive = right of the pen; negative = the ink +// overhangs the pen left — the cell is placed at +// penX + bearingX). +// bearingY the vertical offset of the bitmap's TOP edge ABOVE the +// baseline (positive = above the baseline). +// width/height the bitmap's ink size in texels (0 × 0 = the empty +// glyph — nothing is drawn, the advance still applies). +// +// `lineHeight()` is the line height in px at 1x: by the stbtt +// pixel-height convention the font's ascent + descent is scaled to +// EXACTLY the configured `fontSize`, so `lineHeight() == fontSize()` +// (the formula is documented, not a separate measurement). +// +// --------------------------------------------------------------------------- +// Missing glyphs (the documented fallback) +// --------------------------------------------------------------------------- +// +// `glyph(code)` is a TOTAL function — it never crashes and, for a live +// atlas, never returns null: +// +// - `code` in `[glyphFirst, glyphLast]` → that codepoint's slot. If +// the font has no glyph for the codepoint, the slot holds the font's +// `.notdef` glyph (stbtt maps unknown codepoints to glyph 0) — +// deterministic per font. +// - `code` OUTSIDE the configured range → the FALLBACK glyph: the +// U+0020 (space) slot if `kFontFallbackCode` lies in the configured +// range (the default Latin-1 range does), else `kFontEmptyGlyphMetrics` +// (a zero metric — the advance applies, nothing is drawn). +// +// The fallback is documented, never silent: a game that wants a visible +// "missing character" box configures a glyph range that includes its +// box glyph (the `.notdef` of its font) — the engine does not draw +// extra glyphs. +// +// --------------------------------------------------------------------------- +// Ownership, threading (CORE-009, CONC-001) +// --------------------------------------------------------------------------- +// +// `GlyphAtlas` owns its atlas bytes and slot table (move-only, the +// `SpriteBatcher` precedent); one owner (the scene set-up thread); the +// render phase reads it (the M2-GL-02 cull/batch stage uploads the atlas +// + declares text quads — M2-TEXT-02). Presentation-only (ARCH-009): +// the atlas is never part of the sim state hash or replay state. No GL +// calls anywhere in this header. +// +// Canonical narrative: docs/api/font.md (the full contract). +// The text feature's place in the 2.5D model: +// docs/concepts/coordinates.md (the M2-TEXT-02 row, planned). + +#pragma once + +#include +#include +#include + +#include "laige/errors.h" +#include "laige/result.h" + +namespace laige::render { + +// Named constants (CORE-005). +// +// The atlas dimension domain: [1, kFontMaxAtlasDimension]. 4096² = 16 +// 777 216 texels (16 MiB at 8-bit alpha) — far beyond the practical +// driver maxTextureSize (16K) for a single glyph atlas. +inline constexpr std::uint32_t kFontMaxAtlasDimension = 4096; +// The configured pixel-height domain: [1, kFontMaxFontSize] px at 1x. +// 1024 px is beyond any practical UI text size; the rasterizer's float +// domain (the pixel box stays < 2^31 for every unitsPerEm) is never +// approached. +inline constexpr std::uint32_t kFontMaxFontSize = 1024; +// The glyph-range domain: codepoints up to U+10FFFF (the Unicode +// ceiling); the RANGE SIZE is bounded by kFontMaxGlyphCount (a full +// 1.1M-codepoint range would rasterize minutes of set-up work — the +// documented budget guardrail, PERF-008). +inline constexpr std::uint32_t kFontMaxGlyphCode = 0x10FFFF; +inline constexpr std::uint32_t kFontMaxGlyphCount = 8192; +// The defaults (the Latin-1 set, the FR-2.8 P0 scope: 32..126 printable +// ASCII + 160..255 the Latin-1 supplement; 127..159 C1 controls rasterize +// to the font's .notdef — harmless, deterministic). +inline constexpr std::uint32_t kFontDefaultAtlasWidth = 1024; +inline constexpr std::uint32_t kFontDefaultAtlasHeight = 1024; +inline constexpr std::uint32_t kFontDefaultFontSize = 16; +inline constexpr std::uint32_t kFontDefaultGlyphFirst = 32; // U+0020 SPACE +inline constexpr std::uint32_t kFontDefaultGlyphLast = 255; // U+00FF +// The documented fallback glyph (the header preamble): U+0020 SPACE. +inline constexpr std::uint32_t kFontFallbackCode = 32; + +// Per-glyph metrics + the atlas cell origin (px at 1x, the header +// preamble). Plain value: no ownership, no lifetime beyond the atlas +// that stores it. +struct GlyphMetrics { + std::int32_t advance{0}; // pen advance, px at 1x + std::int32_t bearingX{0}; // bitmap left edge from the pen (right positive) + std::int32_t bearingY{0}; // bitmap top edge above the baseline (up positive) + std::int32_t width{0}; // bitmap ink width, texels (0 = empty glyph) + std::int32_t height{0}; // bitmap ink height, texels (0 = empty glyph) + std::uint32_t atlasX{0}; // cell top-left, texels in the atlas + std::uint32_t atlasY{0}; + + // Field-wise equality (the deterministic-comparison test needs it; + // the house idiom — no synthesized ==, the SpriteUvRect precedent). + [[nodiscard]] bool operator==(const GlyphMetrics& other) const noexcept { + return advance == other.advance && bearingX == other.bearingX && + bearingY == other.bearingY && width == other.width && + height == other.height && atlasX == other.atlasX && + atlasY == other.atlasY; + } +}; + +// The zero metric: the out-of-range fallback when the configured glyph +// range does not include the fallback code (the header preamble). +inline constexpr GlyphMetrics kFontEmptyGlyphMetrics{}; + +// The configured bitmap glyph atlas (M2-TEXT-01). +class GlyphAtlas { + public: + // The create options (API-006): see the header preamble for the + // documented units. + struct Options { + std::uint32_t atlasWidth{kFontDefaultAtlasWidth}; + std::uint32_t atlasHeight{kFontDefaultAtlasHeight}; + std::uint32_t fontSize{kFontDefaultFontSize}; + std::uint32_t glyphFirst{kFontDefaultGlyphFirst}; + std::uint32_t glyphLast{kFontDefaultGlyphLast}; + }; + + // Rasterizes the configured glyph range of `font` into the atlas + // (set-up path — the only allocations: the atlas bytes + the slot + // table). Validation order, first failure wins: + // 1. atlasWidth/atlasHeight in [1, kFontMaxAtlasDimension], + // fontSize in [1, kFontMaxFontSize], + // glyphFirst ≤ glyphLast ≤ kFontMaxGlyphCode, + // (glyphLast − glyphFirst + 1) ≤ kFontMaxGlyphCount + // (InvalidArgument, no log — the M2-SPRITE-01 create precedent); + // 2. the font bytes: a non-font / truncated / corrupt file → + // MalformedInput + one Error `font/font_invalid`; + // 3. a glyph whose cell does not fit the fixed atlas → + // BudgetExhausted + one Error `font/atlas_full` (fields: the + // codepoint, its cell size, the atlas size). + // A failed create returns the error; no atlas is produced. + [[nodiscard]] static laige::Result + create(std::span font, Options options) noexcept; + + // The stopped state (default / moved-from): `valid()` false, + // `glyph()` returns null, `atlas()` empty, introspection zero — the + // RenderThread stopped-state precedent. Nothing owned. + GlyphAtlas() noexcept = default; + + GlyphAtlas(const GlyphAtlas&) = delete; + GlyphAtlas& operator=(const GlyphAtlas&) = delete; + GlyphAtlas(GlyphAtlas&&) noexcept = default; + GlyphAtlas& operator=(GlyphAtlas&&) noexcept = default; + ~GlyphAtlas() noexcept = default; + + // True iff the atlas is live (create succeeded). + [[nodiscard]] bool valid() const noexcept { return !atlas_.empty(); } + + // The atlas dimensions (texels; zero in the stopped state). + [[nodiscard]] std::uint32_t atlasWidth() const noexcept { return atlasWidth_; } + [[nodiscard]] std::uint32_t atlasHeight() const noexcept { return atlasHeight_; } + + // The configured pixel height, px at 1x. + [[nodiscard]] std::uint32_t fontSize() const noexcept { return fontSize_; } + + // The line height, px at 1x: `fontSize()` (the stbtt pixel-height + // convention — the header preamble). + [[nodiscard]] std::uint32_t lineHeight() const noexcept { return fontSize_; } + + // The configured glyph range (inclusive). + [[nodiscard]] std::uint32_t glyphFirst() const noexcept { return glyphFirst_; } + [[nodiscard]] std::uint32_t glyphLast() const noexcept { return glyphLast_; } + + // The atlas bytes: 8-bit alpha, row-major, `atlasWidth() × atlasHeight()` + // texels (empty in the stopped state). The render read path: the + // M2-TEXT-02 pass uploads this as a white-on-alpha RGBA8 atlas + // (the M2-SPRITE-02 `bindAtlas` contract). O(1); never writes. + [[nodiscard]] std::span atlas() const noexcept { + return atlas_; + } + + // The metrics for `code` (the header preamble: a total function — + // null only in the stopped state; the in-range slot, else the + // documented fallback). O(1); no allocation, no logging, no GL. + // The returned pointer is valid until this atlas is moved/destroyed + // (the slot table is member storage, never reallocated after + // create). + [[nodiscard]] const GlyphMetrics* glyph(std::uint32_t code) const noexcept; + + private: + std::vector atlas_; // atlasWidth_ × atlasHeight_ + std::vector slots_; // one per codepoint in [glyphFirst_, glyphLast_] + std::uint32_t atlasWidth_{0}; + std::uint32_t atlasHeight_{0}; + std::uint32_t fontSize_{0}; + std::uint32_t glyphFirst_{0}; + std::uint32_t glyphLast_{0}; +}; + +} // namespace laige::render diff --git a/src/laige-render/stb_truetype_impl.cpp b/src/laige-render/stb_truetype_impl.cpp new file mode 100644 index 0000000..97d01fe --- /dev/null +++ b/src/laige-render/stb_truetype_impl.cpp @@ -0,0 +1,13 @@ +// M2-TEXT-01 (ADR 0009): the single translation unit that compiles +// stb_truetype's implementation (the pinned vendored header, +// deps/stb/stb_truetype.h, deps.lock). +// +// Pinned vendor code (DEP-005) keeps the plain compiler policy — the +// laige-glad precedent (ADR 0007): the engine's -Wall -Werror policy +// does not gate upstream code, and the vendor tree stays byte-pinned +// by the deps.lock hash. The engine's boundary is font.cpp (which +// includes the same header for its DECLARATIONS and links this +// target); the public header names no stb type (CPP-010, DEP-004). + +#define STB_TRUETYPE_IMPLEMENTATION +#include "stb_truetype.h" diff --git a/tests/laige-render/CMakeLists.txt b/tests/laige-render/CMakeLists.txt index b8cfc35..7b24b93 100644 --- a/tests/laige-render/CMakeLists.txt +++ b/tests/laige-render/CMakeLists.txt @@ -197,10 +197,11 @@ # `tilemap` entry is the M2-TILE-01 Verify command (`ctest -R # tilemap`), the `tilemap_anim` entry is the M2-TILE-02 Verify command # (`ctest -R tilemap_anim`), the `parallax` entry is the M2-PAR-01 -# Verify command (`ctest -R parallax`), and the `particle_render` -# entry is the M2-PART-02 Verify command (`ctest -R -# particle_render`), each selecting exactly its suites from the -# shared executable. (The unanchored `ctest -R tilemap` regex also +# Verify command (`ctest -R parallax`), the `particle_render` entry +# is the M2-PART-02 Verify command (`ctest -R +# particle_render`), and the `font` entry is the M2-TEXT-01 Verify +# command (`ctest -R font`), each selecting exactly its suites from +# the shared executable. (The unanchored `ctest -R tilemap` regex also # selects the `tilemap_anim` entry — the M2-TILE-02 suites run under # the M2-TILE-01 command too; that is intended. Likewise the # unanchored `ctest -R particle` regex selects the M2-PART-01 @@ -216,7 +217,8 @@ # documented environment contract (docs/api/gl_context.md), not an # engine failure. The GlContextGate/GlContextArgs/FrameClock/ # RenderThreadHandoff/SpriteDrawCreate/RenderCountersCreate/TileMap*/ -# TileMapAnim*/Parallax* suites always run (they make no GL calls). +# TileMapAnim*/Parallax*/Font* suites always run (they make no GL +# calls). add_executable(laige-render_tests gl_context_tests.cpp render_thread_tests.cpp matrices_tests.cpp @@ -224,7 +226,8 @@ add_executable(laige-render_tests iso_camera_tests.cpp projection_tests.cpp iso_picking_tests.cpp depth_sort_tests.cpp sprite_batcher_tests.cpp sprite_draw_tests.cpp sprite_frames_tests.cpp render_counters_tests.cpp tilemap_tests.cpp - tilemap_anim_tests.cpp parallax_tests.cpp particle_render_tests.cpp) + tilemap_anim_tests.cpp parallax_tests.cpp particle_render_tests.cpp + font_tests.cpp) laige_apply_engine_policy(laige-render_tests) target_link_libraries(laige-render_tests PRIVATE gtest_main laige-render) # The randomized suites draw through the test-only seed helper @@ -235,9 +238,11 @@ target_include_directories(laige-render_tests PRIVATE add_test(NAME laige-render_tests COMMAND laige-render_tests) # The unfiltered entry also runs the M2-ISO-02 budget suite (in the # gated builds it checks the entry), so it carries the same budgets -# path: +# path; the Font* suites (M2-TEXT-01) read the committed test font +# through the LAIGE_TEST_FONT_PATH env var (tests/laige-render/assets/ +# vera.ttf — see the assets/ README for the provenance and license): set_tests_properties(laige-render_tests PROPERTIES - ENVIRONMENT "LAIGE_BUDGETS_PATH=${CMAKE_SOURCE_DIR}/budgets.json") + ENVIRONMENT "LAIGE_BUDGETS_PATH=${CMAKE_SOURCE_DIR}/budgets.json;LAIGE_TEST_FONT_PATH=${CMAKE_SOURCE_DIR}/tests/laige-render/assets/vera.ttf") # M2-GL-01: the step's Verify command is `ctest -R gl_context`. The # gtest filter is one UNQUOTED argument (see @@ -399,6 +404,20 @@ add_test(NAME particle_render COMMAND laige-render_tests set_tests_properties(particle_render PROPERTIES ENVIRONMENT "LAIGE_BUDGETS_PATH=${CMAKE_SOURCE_DIR}/budgets.json") +# M2-TEXT-01: the step's Verify command is `ctest -R font`. Pure engine +# data (no GL calls) — runs in every local tree and in CI. The +# LAIGE_TEST_FONT_PATH env var points the suites at the committed test +# font (tests/laige-render/assets/vera.ttf — the assets/ README +# documents the provenance and the OFL 1.1 license). No budget gate: +# the step's roadmap scope has no standalone budgets.json entry (the +# atlas is built once at scene set-up — the per-frame text cost lands +# with M2-TEXT-02, part of the composite 50k render-CPU budget, +# M2-PERF-01). +add_test(NAME font COMMAND laige-render_tests --gtest_filter=Font*) +set_tests_properties(font PROPERTIES + ENVIRONMENT + "LAIGE_TEST_FONT_PATH=${CMAKE_SOURCE_DIR}/tests/laige-render/assets/vera.ttf") + if(NOT LAIGE_ASAN AND NOT LAIGE_TSAN AND CMAKE_SYSTEM_NAME STREQUAL "Linux") target_compile_definitions(laige-render_tests PRIVATE LAIGE_ISO_DEPTH_BUDGET=1) target_compile_definitions(laige-render_tests PRIVATE LAIGE_ISO_PICK_BUDGET=1) @@ -439,9 +458,10 @@ if(LAIGE_TSAN) set_tests_properties(laige-render_tests gl_context render_thread matrices iso_depth_key iso_depth_table camera iso_camera projection iso_picking depth_sort batcher sprite_draw sprite_frames - render_counters tilemap tilemap_anim parallax particle_render PROPERTIES + render_counters tilemap tilemap_anim parallax particle_render font + PROPERTIES ENVIRONMENT - "TSAN_OPTIONS=halt_on_error=1;LAIGE_BUDGETS_PATH=${CMAKE_SOURCE_DIR}/budgets.json") + "TSAN_OPTIONS=halt_on_error=1;LAIGE_BUDGETS_PATH=${CMAKE_SOURCE_DIR}/budgets.json;LAIGE_TEST_FONT_PATH=${CMAKE_SOURCE_DIR}/tests/laige-render/assets/vera.ttf") endif() if(LAIGE_ASAN) @@ -465,10 +485,12 @@ if(LAIGE_ASAN) # stays fully active (the smoke still performs its GL work under # the sanitizer). The test-level ENVIRONMENT replaces the job-level # ASAN_OPTIONS (GitHub workflow), so mirror its options here. + # The unfiltered entry runs the Font* suites too (M2-TEXT-01), so the + # replacement environment carries the test-font path as well. set_tests_properties(laige-render_tests gl_context render_thread sprite_draw render_counters PROPERTIES ENVIRONMENT - "ASAN_OPTIONS=abort_on_error=1:halt_on_error=1:detect_leaks=0:log_path=${CMAKE_SOURCE_DIR}/asan-reports/asan") + "ASAN_OPTIONS=abort_on_error=1:halt_on_error=1:detect_leaks=0:log_path=${CMAKE_SOURCE_DIR}/asan-reports/asan;LAIGE_TEST_FONT_PATH=${CMAKE_SOURCE_DIR}/tests/laige-render/assets/vera.ttf") endif() # The offscreen smoke creates a real (software) context + FBO; give a @@ -512,3 +534,7 @@ set_tests_properties(parallax PROPERTIES TIMEOUT 60) set_tests_properties(iso_depth_table PROPERTIES TIMEOUT 120) set_tests_properties(depth_sort PROPERTIES TIMEOUT 120) set_tests_properties(particle_render PROPERTIES TIMEOUT 120) +# The `font` entry rasterizes the full Latin-1 range of the test font +# a few times (create + determinism re-creates) — small work, 60s is +# generous headroom, like the other pure-data entries. +set_tests_properties(font PROPERTIES TIMEOUT 60) diff --git a/tests/laige-render/assets/README.md b/tests/laige-render/assets/README.md new file mode 100644 index 0000000..4501def --- /dev/null +++ b/tests/laige-render/assets/README.md @@ -0,0 +1,29 @@ +# laige-render test assets + +Committed test assets for `tests/laige-render`. Test assets are inputs, +not engine code: the test executables read them at run time (the path +is handed over the CTest `ENVIRONMENT`, e.g. `LAIGE_TEST_FONT_PATH` — +see `tests/laige-render/CMakeLists.txt`), never at configure time. + +## vera.ttf + +**Bitstream Vera Sans** (regular), 65 932 bytes — the committed test +font for the M2-TEXT-01 font atlas suites (`font_tests.cpp`). + +- **License:** SIL Open Font License 1.1 (OFL 1.1) — the license under + which Bitstream Inc. released the Vera font family in 2003; the + canonical license text is at (OFL 1.1 + is a free license with no copyleft and no attribution condition at + embedding; the font file itself carries the copyright line + `Copyright (c) 2003 by Bitstream, Inc.`). +- **Why this font:** the engine's own test asset (no system font is + trusted — P0 runners differ in their font packages, NFR-8.8: the + build and the tests must be reproducible in-tree). It is small + (66 KB), a complete TrueType font with the full default Latin-1 + glyph set (32..255), and stable byte-for-byte (committed under the + repo's `text=auto eol=lf` attributes; the binary is never + transformed). +- **Use:** the M2-TEXT-01 suites pin their metric goldens against THIS + file at `fontSize = 16`; a replacement asset changes the goldens + (the test file records the measured values — re-pin in the same + change). diff --git a/tests/laige-render/assets/vera.ttf b/tests/laige-render/assets/vera.ttf new file mode 100644 index 0000000..58cd6b5 Binary files /dev/null and b/tests/laige-render/assets/vera.ttf differ diff --git a/tests/laige-render/font_tests.cpp b/tests/laige-render/font_tests.cpp new file mode 100644 index 0000000..0d39889 --- /dev/null +++ b/tests/laige-render/font_tests.cpp @@ -0,0 +1,682 @@ +// laige-render bitmap font atlas tests (M2-TEXT-01): the configured +// font + glyph range rasterized ONCE at scene set-up into a fixed-size +// 8-bit alpha atlas + per-glyph metrics (advance, bearing, line height) +// — in laige/render/font.h. +// +// Pure engine data (no GL context, no GL environment needed): every +// suite runs in every local tree and in CI. The metric goldens are +// MEASURED against the committed test font (tests/laige-render/assets/ +// vera.ttf — Bitstream Vera Sans, OFL 1.1, see the assets/ README) at +// fontSize 16: the font is a committed in-tree asset (P0 runners differ +// in their font packages, NFR-8.8 — no system font is trusted), so the +// values are stable for the life of the asset. The determinism contract +// is IN-PROCESS (same font bytes + options → identical atlas bytes; +// presentation-only float, ARCH-009 — the cross-platform bit-identity +// scope of the M2-PROJ-01/ISO-03 transforms), printed as the +// machine-greppable `font-atlas-determinism` line (docs/testing.md §4). +// +// No budget gate: the step's roadmap scope has no standalone +// budgets.json entry (the atlas is built once at scene set-up — the +// per-frame text cost lands with M2-TEXT-02, part of the composite 50k +// render-CPU budget, M2-PERF-01). +// +// The font bytes come from the LAIGE_TEST_FONT_PATH env var (set by +// the `font` and unfiltered `laige-render_tests` CTest entries — see +// tests/laige-render/CMakeLists.txt). + +#include "laige/render/font.h" + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "gtest/gtest.h" +#include "laige/alloc_watch.h" +#include "laige/errors.h" +#include "laige/logging.h" +#include "laige_test_seed.h" + +namespace { + +using laige::render::GlyphAtlas; +using laige::render::GlyphMetrics; +using laige::render::kFontEmptyGlyphMetrics; +using laige::render::kFontFallbackCode; +using laige::ErrorCode; + +// --------------------------------------------------------------------------- +// The committed test font (tests/laige-render/assets/vera.ttf — the +// LAIGE_TEST_FONT_PATH env var, CTest ENVIRONMENT). +// --------------------------------------------------------------------------- + +std::vector loadFont() { + // The cross-platform env read (tests/support/laige_test_seed.h — MSVC + // deprecates plain getenv under /WX, C4996). + const std::string path = laige::testing::ReadEnvVar("LAIGE_TEST_FONT_PATH"); + if (path.empty()) { + ADD_FAILURE() << "LAIGE_TEST_FONT_PATH is not set (CTest ENVIRONMENT " + "contract — see tests/laige-render/CMakeLists.txt)"; + return {}; + } + // The cross-platform open (fopen_s on MSVC — C4996; a read-only asset + // needs no _SH_DENYNO sharing, so the secure open is the plain form). + std::FILE* f = nullptr; +#if defined(_MSC_VER) + if (fopen_s(&f, path.c_str(), "rb") != 0) { + ADD_FAILURE() << "Cannot open the test font: " << path; + return {}; + } +#else + f = std::fopen(path.c_str(), "rb"); + if (f == nullptr) { + ADD_FAILURE() << "Cannot open the test font: " << path; + return {}; + } +#endif + std::fseek(f, 0, SEEK_END); + const long size = std::ftell(f); + std::fseek(f, 0, SEEK_SET); + std::vector bytes(static_cast(size)); + const std::size_t got = std::fread(bytes.data(), 1, bytes.size(), f); + std::fclose(f); + if (got != bytes.size()) { + ADD_FAILURE() << "Short read of the test font: " << path; + return {}; + } + return bytes; +} + +GlyphAtlas makeDefaultAtlas() { + std::vector font = loadFont(); + auto r = GlyphAtlas::create(font, GlyphAtlas::Options{}); + if (!r.ok()) { + std::fprintf(stderr, "makeDefaultAtlas: create failed\n"); + std::abort(); + } + return std::move(r).takeValue(); +} + +std::vector makeDefaultBytes() { + std::vector font = loadFont(); + auto r = GlyphAtlas::create(font, GlyphAtlas::Options{}); + if (!r.ok()) { + std::fprintf(stderr, "makeDefaultBytes: create failed\n"); + std::abort(); + } + const GlyphAtlas atlas = std::move(r).takeValue(); + return std::vector(atlas.atlas().begin(), atlas.atlas().end()); +} + +// FNV-1a 64 over a byte span (the machine-greppable fingerprint +// convention, docs/testing.md §4 — the particlesFnv1a64 pattern). +std::uint64_t atlasFnv1a64(const std::uint8_t* bytes, std::size_t n) { + std::uint64_t h = 0xcbf29ce484222325ull; // FNV offset basis (FNV-1a spec) + for (std::size_t i = 0; i < n; ++i) { + h ^= static_cast(bytes[i]); + h *= 0x10000001b3ull; // FNV prime (FNV-1a spec) + } + return h; +} + +// --------------------------------------------------------------------------- +// Log capture (the tilemap_tests MemorySink pattern) +// --------------------------------------------------------------------------- + +class MemorySink : public laige::log::Sink { + public: + struct Entry { + laige::log::Severity severity{}; + std::string subsystem; + std::string event; + std::string message; + }; + + void emit(const laige::log::LogRecord& record) override { + Entry e; + e.severity = record.severity; + e.subsystem = record.subsystem; + e.event = record.event; + e.message = record.message; + entries.push_back(std::move(e)); + } + void flush() override {} + + std::vector entries; +}; + +MemorySink* installCaptureSink() { + auto sink = std::make_unique(); + MemorySink* ptr = sink.get(); + laige::log::LoggerOptions opts; + opts.sink = std::move(sink); + opts.rateLimiting = false; + if (!laige::log::Logger::instance().init(std::move(opts)).ok()) { + ADD_FAILURE() << "Logger::init (capture sink) failed"; + std::abort(); + } + return ptr; +} + +void restoreLogger() { + laige::log::LoggerOptions defaults; + if (!laige::log::Logger::instance().init(std::move(defaults)).ok()) { + ADD_FAILURE() << "Logger::init (restore default sink) failed"; + } +} + +} // namespace + +// --------------------------------------------------------------------------- +// FontCreate — the create validation matrix (first failure wins), the +// untrusted-font boundary (SCALE-004), the stopped state, the capacity +// guard, and the move semantics +// --------------------------------------------------------------------------- + +TEST(FontCreate, OptionsValidation) { + std::vector font = loadFont(); + MemorySink* sink = installCaptureSink(); + struct Case { + GlyphAtlas::Options options; + const char* name; + }; + const std::vector cases = { + {GlyphAtlas::Options{.atlasWidth = 0}, "atlasWidth zero"}, + {GlyphAtlas::Options{.atlasWidth = laige::render::kFontMaxAtlasDimension + 1}, + "atlasWidth above the domain"}, + {GlyphAtlas::Options{.atlasHeight = 0}, "atlasHeight zero"}, + {GlyphAtlas::Options{.atlasHeight = laige::render::kFontMaxAtlasDimension + 1}, + "atlasHeight above the domain"}, + {GlyphAtlas::Options{.fontSize = 0}, "fontSize zero"}, + {GlyphAtlas::Options{.fontSize = laige::render::kFontMaxFontSize + 1}, + "fontSize above the domain"}, + {GlyphAtlas::Options{.glyphFirst = 100, .glyphLast = 99}, + "glyphFirst above glyphLast"}, + {GlyphAtlas::Options{.glyphLast = laige::render::kFontMaxGlyphCode + 1}, + "glyphLast above the Unicode ceiling"}, + {GlyphAtlas::Options{.glyphFirst = 0, .glyphLast = laige::render::kFontMaxGlyphCount}, + "glyph range above the size bound"}, + }; + for (const Case& c : cases) { + auto r = GlyphAtlas::create(font, c.options); + EXPECT_TRUE(r.isError()) << c.name; + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::InvalidArgument) << c.name; + } + } + EXPECT_EQ(sink->entries.size(), 0u); // no log — the create precedent + restoreLogger(); +} + +TEST(FontCreate, EmptyOrTruncatedFont) { + MemorySink* sink = installCaptureSink(); + const std::vector empty; + auto r = GlyphAtlas::create(empty, GlyphAtlas::Options{}); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::MalformedInput); + } + // A buffer shorter than the header + table directory guard (12 + // bytes) — rejected before any stb read (SCALE-004). + const std::vector shortBuf(10, 0xAB); + r = GlyphAtlas::create(shortBuf, GlyphAtlas::Options{}); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::MalformedInput); + } + // A valid font cut inside the table directory: the guard rejects it + // (the directory is longer than the buffer) — never read past. + std::vector font = loadFont(); + auto rCut = GlyphAtlas::create( + std::span(font.data(), 16), + GlyphAtlas::Options{}); + EXPECT_TRUE(rCut.isError()); + if (rCut.isError()) { + EXPECT_EQ(rCut.error(), ErrorCode::MalformedInput); + } + // Exactly one structured Error per rejection (LOG-002). + const std::size_t errors = static_cast(std::count_if( + sink->entries.begin(), sink->entries.end(), + [](const MemorySink::Entry& e) { + return e.severity == laige::log::Severity::Error && + e.subsystem == "font" && e.event == "font_invalid"; + })); + EXPECT_EQ(errors, 3u); + restoreLogger(); +} + +// Patches the hhea table's ascent/descent (big-endian i16 at offsets +// 4/6 within the table — the table the pinned stb's +// stbtt_ScaleForPixelHeight reads) to make the font's vertical metrics +// degenerate (the SCALE-004 guard's test input). +bool patchHheaMetrics(std::vector& font, std::int16_t ascent, + std::int16_t descent) { + if (font.size() < 12) { + return false; + } + const std::uint32_t numTables = + (static_cast(font[4]) << 8) | + static_cast(font[5]); + for (std::uint32_t i = 0; i < numTables; ++i) { + const std::size_t e = 12 + 16 * i; + if (e + 16 > font.size()) { + return false; + } + if (font[e] == 'h' && font[e + 1] == 'h' && font[e + 2] == 'e' && + font[e + 3] == 'a') { + const std::uint32_t off = + (static_cast(font[e + 8]) << 24) | + (static_cast(font[e + 9]) << 16) | + (static_cast(font[e + 10]) << 8) | + static_cast(font[e + 11]); + if (off + 8 > font.size()) { + return false; + } + const std::uint16_t a = static_cast(ascent); + font[off + 4] = static_cast(a >> 8); + font[off + 5] = static_cast(a & 0xFF); + const std::uint16_t d = static_cast(descent); + font[off + 6] = static_cast(d >> 8); + font[off + 7] = static_cast(d & 0xFF); + return true; + } + } + return false; +} + +TEST(FontCreate, DegenerateVerticalMetrics) { + MemorySink* sink = installCaptureSink(); + std::vector font = loadFont(); + // ascent == descent → the pixel-height scale is inf → MalformedInput. + ASSERT_TRUE(patchHheaMetrics(font, 1000, 1000)); + auto r = GlyphAtlas::create(font, GlyphAtlas::Options{}); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::MalformedInput); + } + // descent > ascent → the scale is negative → MalformedInput. + ASSERT_TRUE(patchHheaMetrics(font, 1000, 2000)); + r = GlyphAtlas::create(font, GlyphAtlas::Options{}); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::MalformedInput); + } + const std::size_t errors = static_cast(std::count_if( + sink->entries.begin(), sink->entries.end(), + [](const MemorySink::Entry& e) { + return e.severity == laige::log::Severity::Error && + e.subsystem == "font" && e.event == "font_invalid"; + })); + EXPECT_EQ(errors, 2u); + restoreLogger(); +} + +TEST(FontCreate, NotAFont) { + MemorySink* sink = installCaptureSink(); + const std::vector garbage(64, 0xFF); + auto r = GlyphAtlas::create(garbage, GlyphAtlas::Options{}); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::MalformedInput); + } + EXPECT_EQ(sink->entries.size(), 1u); + if (!sink->entries.empty()) { + EXPECT_EQ(sink->entries.front().subsystem, "font"); + EXPECT_EQ(sink->entries.front().event, "font_invalid"); + EXPECT_EQ(sink->entries.front().severity, laige::log::Severity::Error); + } + restoreLogger(); +} + +TEST(FontCreate, StoppedState) { + GlyphAtlas atlas; + EXPECT_FALSE(atlas.valid()); + EXPECT_EQ(atlas.glyph('A'), nullptr); + EXPECT_TRUE(atlas.atlas().empty()); + EXPECT_EQ(atlas.atlasWidth(), 0u); + EXPECT_EQ(atlas.atlasHeight(), 0u); + EXPECT_EQ(atlas.fontSize(), 0u); + EXPECT_EQ(atlas.lineHeight(), 0u); + EXPECT_EQ(atlas.glyphFirst(), 0u); + EXPECT_EQ(atlas.glyphLast(), 0u); +} + +TEST(FontCreate, CapacityFull) { + std::vector font = loadFont(); + MemorySink* sink = installCaptureSink(); + // 8 x 8 cannot hold a 16 px glyph (its ink is taller than the atlas). + GlyphAtlas::Options small; + small.atlasWidth = 8; + small.atlasHeight = 8; + auto r = GlyphAtlas::create(font, small); + EXPECT_TRUE(r.isError()); + if (r.isError()) { + EXPECT_EQ(r.error(), ErrorCode::BudgetExhausted); + } + const std::size_t errors = static_cast(std::count_if( + sink->entries.begin(), sink->entries.end(), + [](const MemorySink::Entry& e) { + return e.severity == laige::log::Severity::Error && + e.subsystem == "font" && e.event == "atlas_full"; + })); + EXPECT_EQ(errors, 1u); + restoreLogger(); +} + +TEST(FontCreate, SuccessIntrospection) { + MemorySink* sink = installCaptureSink(); + const GlyphAtlas atlas = makeDefaultAtlas(); + EXPECT_TRUE(atlas.valid()); + EXPECT_EQ(atlas.atlasWidth(), laige::render::kFontDefaultAtlasWidth); + EXPECT_EQ(atlas.atlasHeight(), laige::render::kFontDefaultAtlasHeight); + EXPECT_EQ(atlas.fontSize(), laige::render::kFontDefaultFontSize); + EXPECT_EQ(atlas.glyphFirst(), laige::render::kFontDefaultGlyphFirst); + EXPECT_EQ(atlas.glyphLast(), laige::render::kFontDefaultGlyphLast); + EXPECT_EQ(atlas.atlas().size(), + static_cast(laige::render::kFontDefaultAtlasWidth) * + static_cast(laige::render::kFontDefaultAtlasHeight)); + // Exactly one Info on the set-up path (LOG-002; the lookup path logs + // nothing). + const std::size_t infos = static_cast(std::count_if( + sink->entries.begin(), sink->entries.end(), + [](const MemorySink::Entry& e) { + return e.severity == laige::log::Severity::Info && + e.subsystem == "font" && e.event == "atlas_created"; + })); + EXPECT_EQ(infos, 1u); + restoreLogger(); +} + +TEST(FontCreate, MoveSemantics) { + auto r = GlyphAtlas::create(loadFont(), GlyphAtlas::Options{}); + ASSERT_TRUE(r.ok()); + GlyphAtlas live = std::move(r).takeValue(); + EXPECT_TRUE(live.valid()); + GlyphAtlas stopped; + stopped = std::move(live); + EXPECT_TRUE(stopped.valid()); + EXPECT_FALSE(live.valid()); // moved-from is the stopped state + EXPECT_EQ(live.glyph('A'), nullptr); + EXPECT_NE(stopped.glyph('A'), nullptr); // the moved-into atlas is intact + GlyphAtlas third = std::move(stopped); + EXPECT_TRUE(third.valid()); + EXPECT_FALSE(stopped.valid()); + EXPECT_EQ(stopped.glyph('A'), nullptr); + EXPECT_NE(third.glyph('A'), nullptr); +} + +// --------------------------------------------------------------------------- +// FontMetrics — the documented units (px at 1x) pinned against the +// committed test font (Vera Sans, fontSize 16) +// --------------------------------------------------------------------------- + +TEST(FontMetrics, AsciiGoldens) { + const GlyphAtlas atlas = makeDefaultAtlas(); + // Space (U+0020): no ink, a positive advance (the fallback glyph). + const GlyphMetrics* space = atlas.glyph(' '); + ASSERT_NE(space, nullptr); + EXPECT_EQ(space->advance, 4); + EXPECT_EQ(space->width, 0); + EXPECT_EQ(space->height, 0); + EXPECT_EQ(space->bearingX, 0); + EXPECT_EQ(space->bearingY, 0); + // 'M' (U+004D): a wide uppercase, full height of the caps line. + const GlyphMetrics* m = atlas.glyph('M'); + ASSERT_NE(m, nullptr); + EXPECT_EQ(m->advance, 12); + EXPECT_EQ(m->width, 10); + EXPECT_EQ(m->height, 11); + EXPECT_EQ(m->bearingX, 1); + EXPECT_EQ(m->bearingY, 11); + // 'a' (U+0061): a lowercase with a left overhang-free box. + const GlyphMetrics* a = atlas.glyph('a'); + ASSERT_NE(a, nullptr); + EXPECT_EQ(a->advance, 8); + EXPECT_EQ(a->width, 8); + EXPECT_EQ(a->height, 9); + EXPECT_EQ(a->bearingX, 0); + EXPECT_EQ(a->bearingY, 8); + // 'W' (U+0057): the widest Latin-1 uppercase. + const GlyphMetrics* w = atlas.glyph('W'); + ASSERT_NE(w, nullptr); + EXPECT_EQ(w->advance, 14); + EXPECT_EQ(w->width, 14); + EXPECT_EQ(w->height, 11); + EXPECT_EQ(w->bearingX, 0); + EXPECT_EQ(w->bearingY, 11); + // '.' (U+002E): a small ink with a left bearing (the overhang-free + // dot sits one texel right of the pen). + const GlyphMetrics* dot = atlas.glyph('.'); + ASSERT_NE(dot, nullptr); + EXPECT_EQ(dot->advance, 4); + EXPECT_EQ(dot->width, 2); + EXPECT_EQ(dot->height, 2); + EXPECT_EQ(dot->bearingX, 1); + EXPECT_EQ(dot->bearingY, 2); +} + +TEST(FontMetrics, DescenderAndAdvance) { + const GlyphAtlas atlas = makeDefaultAtlas(); + // 'g' (U+0067): a descender — the ink bottom lies BELOW the baseline, + // i.e. height > bearingY (the documented relation), while the top + // still sits above it. + const GlyphMetrics* g = atlas.glyph('g'); + ASSERT_NE(g, nullptr); + EXPECT_GT(g->height, g->bearingY); + EXPECT_GT(g->bearingY, 0); + // Every A..z Latin-1 glyph of the test font advances the pen + // (positive advance — the documented metric domain for this set). + for (std::uint32_t code = 'A'; code <= 'z'; ++code) { + const GlyphMetrics* m = atlas.glyph(code); + ASSERT_NE(m, nullptr); + EXPECT_GT(m->advance, 0) << "code " << code; + } +} + +TEST(FontMetrics, LineHeightIsPixelHeight) { + const GlyphAtlas atlas = makeDefaultAtlas(); + // The stbtt pixel-height convention: the font's ascent + descent is + // scaled to exactly the configured pixel height (font.h preamble). + EXPECT_EQ(atlas.lineHeight(), atlas.fontSize()); + EXPECT_EQ(atlas.lineHeight(), laige::render::kFontDefaultFontSize); +} + +// --------------------------------------------------------------------------- +// FontDeterminism — same font bytes + options → identical atlas bytes +// (the roadmap Verify property; presentation-only float, ARCH-009, so +// the scope is in-process / same-build) +// --------------------------------------------------------------------------- + +TEST(FontDeterminism, IdenticalBytes) { + const std::vector b1 = makeDefaultBytes(); + const std::vector b2 = makeDefaultBytes(); + EXPECT_EQ(b1.size(), b2.size()); + EXPECT_EQ(std::equal(b1.begin(), b1.end(), b2.begin()), true); + const GlyphAtlas a1 = makeDefaultAtlas(); + const GlyphAtlas a2 = makeDefaultAtlas(); + for (std::uint32_t code = a1.glyphFirst(); code <= a1.glyphLast(); ++code) { + const GlyphMetrics* m1 = a1.glyph(code); + const GlyphMetrics* m2 = a2.glyph(code); + ASSERT_NE(m1, nullptr); + ASSERT_NE(m2, nullptr); + EXPECT_EQ(*m1, *m2) << "code " << code; // GlyphMetrics is a value + } + // The machine-greppable fingerprint (docs/testing.md §4 — no pinned + // value: the determinism contract is in-process, the hash records the + // build's output for run-to-run comparison). + std::printf("font-atlas-determinism font=vera.ttf size=%u glyphs=%u " + "atlas=%ux%u fnv1a=0x%016llx\n", + static_cast(a1.fontSize()), + static_cast(a1.glyphLast() - a1.glyphFirst() + 1), + static_cast(a1.atlasWidth()), + static_cast(a1.atlasHeight()), + static_cast( + atlasFnv1a64(b1.data(), b1.size()))); +} + +TEST(FontDeterminism, SizeDiverges) { + std::vector font = loadFont(); + auto r1 = GlyphAtlas::create(font, GlyphAtlas::Options{}); + ASSERT_TRUE(r1.ok()); + GlyphAtlas::Options big = GlyphAtlas::Options{}; + big.fontSize = 32; + auto r2 = GlyphAtlas::create(font, big); + ASSERT_TRUE(r2.ok()); + const GlyphAtlas a1 = std::move(r1).takeValue(); + const GlyphAtlas a2 = std::move(r2).takeValue(); + EXPECT_NE(atlasFnv1a64(a1.atlas().data(), a1.atlas().size()), + atlasFnv1a64(a2.atlas().data(), a2.atlas().size())); + EXPECT_NE(a1.glyph('M')->width, a2.glyph('M')->width); +} + +TEST(FontDeterminism, RangeDiverges) { + std::vector font = loadFont(); + auto r1 = GlyphAtlas::create(font, GlyphAtlas::Options{}); + ASSERT_TRUE(r1.ok()); + GlyphAtlas::Options narrow = GlyphAtlas::Options{}; + narrow.glyphFirst = 'A'; + narrow.glyphLast = 'z'; + auto r2 = GlyphAtlas::create(font, narrow); + ASSERT_TRUE(r2.ok()); + const GlyphAtlas a1 = std::move(r1).takeValue(); + const GlyphAtlas a2 = std::move(r2).takeValue(); + // 'A' is the FIRST glyph in the narrow range (placed at the origin), + // but not in the default range — the packing differs, the bytes + // differ; 'A's OWN metrics are unchanged (same font, same size). + EXPECT_NE(a1.glyph('A')->atlasX, a2.glyph('A')->atlasX); + EXPECT_EQ(a1.glyph('A')->width, a2.glyph('A')->width); + EXPECT_EQ(a1.glyph('A')->bearingX, a2.glyph('A')->bearingX); +} + +// --------------------------------------------------------------------------- +// FontFallback — the documented missing-glyph contract (never a crash, +// never a silent glyph) +// --------------------------------------------------------------------------- + +TEST(FontFallback, InRangeMissingGlyph) { + const GlyphAtlas atlas = makeDefaultAtlas(); + // Two codepoints the test font does not carry (C1 control points, + // inside the default Latin-1 range): stbtt maps unknown codepoints to + // glyph 0 (the font's .notdef) — identical SHAPE metrics (measured + // against the test font: an 8 x 13 box, advance 8), separate cells + // (each codepoint owns its own atlas cell). + const GlyphMetrics* m1 = atlas.glyph(0x0081); + const GlyphMetrics* m2 = atlas.glyph(0x009F); + ASSERT_NE(m1, nullptr); + ASSERT_NE(m2, nullptr); + EXPECT_EQ(m1->advance, 8); + EXPECT_EQ(m1->bearingX, 0); + EXPECT_EQ(m1->bearingY, 10); + EXPECT_EQ(m1->width, 8); + EXPECT_EQ(m1->height, 13); + EXPECT_EQ(m1->advance, m2->advance); + EXPECT_EQ(m1->bearingX, m2->bearingX); + EXPECT_EQ(m1->bearingY, m2->bearingY); + EXPECT_EQ(m1->width, m2->width); + EXPECT_EQ(m1->height, m2->height); + EXPECT_NE(m1->atlasX, m2->atlasX); +} + +TEST(FontFallback, OutOfRangeIsSpace) { + const GlyphAtlas atlas = makeDefaultAtlas(); + // A code just outside the configured range (the default range ends at + // U+00FF) and one far outside it (an emoji): both fall back to the + // documented U+0020 space slot. + const GlyphMetrics* space = atlas.glyph(kFontFallbackCode); + ASSERT_NE(space, nullptr); + EXPECT_EQ(*atlas.glyph(0x0100), *space); + EXPECT_EQ(*atlas.glyph(0x1F600), *space); +} + +TEST(FontFallback, NoSpaceInRangeIsZeroMetric) { + std::vector font = loadFont(); + GlyphAtlas::Options letters; + letters.glyphFirst = 'A'; + letters.glyphLast = 'z'; + auto r = GlyphAtlas::create(font, letters); + ASSERT_TRUE(r.ok()); + const GlyphAtlas atlas = std::move(r).takeValue(); + // The configured range has no space: the out-of-range fallback is the + // zero metric (the documented contract). + EXPECT_EQ(*atlas.glyph(0x100), kFontEmptyGlyphMetrics); + EXPECT_EQ(*atlas.glyph('A'), *atlas.glyph('A')); // sanity: in-range +} + +TEST(FontFallback, StoppedReturnsNull) { + GlyphAtlas atlas; // the stopped state + EXPECT_EQ(atlas.glyph('A'), nullptr); + EXPECT_EQ(atlas.glyph(0x1F600), nullptr); +} + +// --------------------------------------------------------------------------- +// FontAtlas — the atlas invariants: the packing fits the fixed atlas, +// and the ink is present (the rasterizer actually drew) +// --------------------------------------------------------------------------- + +TEST(FontAtlas, CellsFitAtlas) { + const GlyphAtlas atlas = makeDefaultAtlas(); + const std::uint32_t W = atlas.atlasWidth(); + const std::uint32_t H = atlas.atlasHeight(); + for (std::uint32_t code = atlas.glyphFirst(); code <= atlas.glyphLast(); + ++code) { + const GlyphMetrics* m = atlas.glyph(code); + ASSERT_NE(m, nullptr); + if (m->width > 0 && m->height > 0) { + EXPECT_LE(m->atlasX + static_cast(m->width), W) + << "code " << code; + EXPECT_LE(m->atlasY + static_cast(m->height), H) + << "code " << code; + } + } +} + +TEST(FontAtlas, InkIsPresent) { + const GlyphAtlas atlas = makeDefaultAtlas(); + const std::span a = atlas.atlas(); + const std::size_t total = a.size(); + std::size_t nonZero = 0; + std::uint8_t maxCover = 0; + for (std::uint8_t v : a) { + if (v != 0) { + ++nonZero; + } + if (v > maxCover) { + maxCover = v; + } + } + // The Latin-1 ink occupies a small fraction of the 1024 x 1024 + // atlas (most texels are transparent margin), and at least one texel + // is full coverage (a solid stem at 16 px). + EXPECT_GT(nonZero, 100u); + EXPECT_LT(nonZero, total / 4); + EXPECT_EQ(maxCover, 255u); +} + +// --------------------------------------------------------------------------- +// FontZeroAlloc — the per-lookup path allocates nothing (PERF-003: the +// render read path is a pure table lookup) +// --------------------------------------------------------------------------- + +TEST(FontZeroAlloc, LookupZeroAlloc) { + const GlyphAtlas atlas = makeDefaultAtlas(); + laige::allocWatchArm(); + std::int64_t sum = 0; + for (std::uint32_t i = 0; i < 1000; ++i) { + const GlyphMetrics* inRange = atlas.glyph( + atlas.glyphFirst() + i % (atlas.glyphLast() - atlas.glyphFirst() + 1)); + const GlyphMetrics* fallback = atlas.glyph(0x0100 + i); + if (inRange != nullptr) { + sum += inRange->advance; + } + if (fallback != nullptr) { + sum += fallback->advance; + } + } + const laige::AllocWatchReading reading = laige::allocWatchRead(); + EXPECT_EQ(reading.allocs, 0u); + EXPECT_GT(sum, 0); // the lookups actually happened +}