Autotiler

Turn a small terrain template into a complete autotile tileset: the 47-tile blob set or a 16-tile dual grid, ready for Godot 4, Tiled or any engine. Free, open source, and it runs offline.

Get it: desktop apps for macOS, Windows and Linux · web version (nothing to install) · itch.io

Features

• Two template formats in: the Autotiler 13-tile template (5×3 tiles) and the RPG Maker A2 floor autotile (2×3, as in VX Ace, MV and MZ). The template kind and tile size are detected from the image. Any tile size from 2 px works (the dual grid needs an even size).
• Four layouts out: Godot 3×3 minimal (12×4, the layout from the Godot docs), Autotiler v1 (11×5), GameMaker 47 (8×6) and a 16-tile dual grid (4×4, for the TileMapDual addon).
• Exports:
  • Godot 4: a TileSet .tres with a terrain set, the peering bits of all 47 tiles and full-tile collisions. The texture path is relative, so the files work in any folder of your project.
  • Tiled: a .tsx tileset with a Wang set, for the terrain brush.
  • PNG: optionally with a JSON map of each tile's neighbour mask, for custom engines.
  • Godot 3 (legacy): an autotile with the 3×3 minimal bitmask.
• Preview: grid, quarter, peering-bit and collision overlays. An inspector shows each tile's neighbours and bitmask (hover a tile, or focus the tileset and use the arrow keys).
• Test map: paint and erase with the tileset, or fill the map randomly or with every combination. Tiles are picked the way Godot's terrain painter picks them.
• Workflow: open, drag and drop or paste the template. Copy the result back to the clipboard. The app also has examples, blank colour-coded templates, and converts templates between 13-tile and RPG Maker A2.
• Live updates: in the desktop app (and in Chrome or Edge on the web) you can export straight into a folder. Autotiler watches the template and re-exports when you save it, so an edit in Aseprite shows up in Godot.
• Tested: golden-image tests keep the output pixel-exact. The Godot 4 export is checked by painting every terrain combination in headless Godot 4.7.

Templates

Every output tile is assembled from four quarters. Each quarter shows one of five pieces, depending on its neighbours. A template draws each piece at least once:

Autotiler 13-tile (5×3)	RPG Maker A2 (2×3)
A 3×3 island (outer corners, edges and fill) plus a 2×2 block whose centre holds the inner corners. The two bottom-right cells aren't used.	The top-left tile is RPG Maker's palette thumbnail and isn't used. The top-right tile holds the inner corners, and the 2×2 block below is the island.

Colours in the blank templates: 🟥 outer corner · 🟦 horizontal edge · 🟩 vertical edge · 🟨 inner corner · ⬜ fill. Download them from the app's Blank template menu, paint over them and open the result. The app dims the cells it doesn't read, and it warns about empty pieces.

The examples make good starting points too: a meadow, a pond, side-view grassy ground, cobblestone and lava, at 16 px, with 24 and 32 px versions and an RPG Maker A2 meadow. They're rendered by scripts/make-examples.ts, which draws every piece from its distance to the terrain edge, so all 47 tiles join seamlessly.

Using the tileset

Godot 4

1. Pick Godot 4 and export into your project. In the desktop app, choose the folder once: the app shows its res:// path, and every later export is one click.
2. Select a TileMapLayer and load the .tres as its Tile Set.
3. In the TileMap panel, open Terrains, select the terrain and paint (Rect, Path or Connect mode).

For crisp pixel art, set Project Settings → Rendering → Textures → Canvas Textures → Default Texture Filter to Nearest. Or turn on Force nearest filtering before exporting (Godot 4.2+).

Dual grid

Pick the Dual grid layout and export a PNG for TileMapDual. Its tiles use TileMapDual's standard 4×4 order. The same layout exports to Tiled as a corner Wang set.

Tiled

Add the exported .tsx to your map (Map → Add External Tileset…), then paint with the Terrain Brush and the tileset's terrain set.

Other engines

Export the PNG with JSON tile map turned on. For every tile, the JSON lists its position and its 8-bit neighbour mask: N = 1, NE = 2, E = 4, SE = 8, S = 16, SW = 32, W = 64, NW = 128. A corner only counts when both sides next to it are set. For the dual grid it lists the filled corners instead (TL = 1, TR = 2, BL = 4, BR = 8).

RPG Maker

Open a 13-tile template, choose Save as RPG Maker A2, and paste the 2×3 block into an A2 slot of your tileset. It works the other way too, if you want to take A2 art to Godot.

Godot 3

The Godot 3 export writes the PNG, a .png.import with filtering off and an autotile .tres with the 3×3 minimal bitmask and collisions.

Installing

• macOS 13 or later (one universal build for Apple Silicon and Intel). The app is ad-hoc signed but not notarized, so macOS blocks it the first time. Open it once, then go to System Settings → Privacy & Security and click Open Anyway. On macOS 13 and 14 you can also right-click the app and choose Open.
• Windows 10 and 11: the -setup.exe or the .msi. Both need WebView2, which Windows 11 includes; the installer adds it on Windows 10 when it's missing.
• Linux: the .AppImage, .deb or .rpm, with WebKitGTK 4.1. If the window stays blank on an NVIDIA GPU, start the app with WEBKIT_DISABLE_DMABUF_RENDERER=1.
• Web: any current browser. Firefox and Safari download the files (several files come as a .zip), while Chrome and Edge can also write into a folder and reload the template when it changes.

Development

You need Node.js 24 or later and pnpm (the version is pinned in package.json; corepack enable picks it up). The desktop app also needs Rust and the Tauri prerequisites for your OS.

pnpm install
pnpm dev            # web app on http://localhost:5173
pnpm desktop:dev    # desktop app with hot reload
pnpm check          # formatting, lint, type check and unit tests
pnpm test:e2e       # Playwright smoke tests in Chromium and WebKit
pnpm desktop:build  # native bundles in src-tauri/target/release/bundle

Folder	What's in it
src/core	The tileset engine: templates, layouts, generation and exporters. Plain TypeScript with no DOM, React or Node APIs (lint-enforced), so it runs in the browser, the desktop app and Node.
src/app	The React UI. platform/ holds the web and desktop (Tauri) implementations of files, dialogs and settings.
src-tauri	The desktop shell (Tauri 2).
tests	Golden images, the headless Godot check and the Playwright tests.
scripts	make-examples.ts (the example templates and their previews), release.ts (pnpm release-version), update-golden.ts (after an intended output change, review the diff) and screenshots.ts (README images).

The Godot check runs as part of pnpm test when a Godot 4 binary is found (GODOT_BIN, /Applications/Godot.app or godot on the PATH). Otherwise it's skipped.

Releasing: list the changes under ## Unreleased at the top of CHANGELOG.md, then run pnpm release-version patch (or minor, major, or an exact X.Y.Z; --dry-run shows what it would do). It checks that main is clean and up to date, runs pnpm check, sets the version in package.json, src-tauri/Cargo.toml and Cargo.lock, dates the changelog section, then commits and tags vX.Y.Z. Push both (or pass --push) and the release workflow builds every platform into a draft GitHub Release; publishing the draft also pushes the builds to itch.io, once the ITCH_GAME variable and BUTLER_API_KEY secret are set. The web version deploys from main to GitHub Pages.

Feedback

Ideas and requests are welcome in the roadmap thread and in issues.

License

MIT