feat: real text metrics for label layout (DasherCore v0.2.4) - #16
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… #56) Bumps third_party/DasherCore to v0.2.4 and wires the text-size callback: the engine measures labels with the same Paint (typeface + size transform) the canvas draws opcode-5 text with, replacing the codepoints x size/2 estimate whose error compounds down the label chain and jumbles deep-zoom text. - jni_bridge: textSizeCallback marshals into Kotlin NativeBridge.onTextSize (same cached-methodID pattern as the other engine callbacks); nativeSetTextSizeCallback / nativeTextMetricsChanged bindings. - DasherCanvasView.measureGlyphText applies the canvas's exact opcode-5 size transform (x2.5, floored at 8) so measurement and drawing agree; glyphFontName changes fire textMetricsChanged. - MainActivity and the IME both install their own measurement (the NativeBridge listener is static, so the IME must not inherit the Activity's canvas). Signed-off-by: will wade <willwade@gmail.com>
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Supersedes #16 (squash-merged into its stacked base by mistake) and #18 (auto-closed by the same). One PR, two commits, net diff identical to those two combined. ## 1. Real text metrics for label layout ([DasherCore #56](dasher-project/DasherCore#56) / v0.2.4) The engine laid out node labels using a `codepoints × fontSize/2` estimate whose error compounds down the label shunting chain — deep-zoom text degenerates into jumbles (user-visible on Windows; same engine path here). Wires `dasher_set_text_size_callback` end to end: - JNI `textSizeCallback` marshals into `NativeBridge.onTextSize` (same cached-methodID pattern as the other callbacks); new `nativeSetTextSizeCallback` / `nativeTextMetricsChanged`. - `DasherCanvasView.measureGlyphText` measures with the same Paint + size transform (`×2.5, floor 8`) the canvas draws opcode-5 text with, so layout and drawing agree; font changes invalidate cached metrics. - MainActivity **and** the IME install their own measurement (static listeners — the IME must not inherit the Activity's canvas). - Submodule → DasherCore v0.2.4. ## 2. App version line in Settings → Privacy ([RFC 0016](https://github.com/dasher-project/governance/blob/main/rfcs/0016-version-in-settings.md), fixes #17) Quiet `Dasher <version>` line reading `AnalyticsService.appVersion` (`BuildConfig.VERSION_NAME`) — same value analytics reports; UI and telemetry cannot disagree. ## Testing `:app:compileDebugKotlin`, `:app:testDebugUnitTest`, `:app:assembleDebug` (native vs v0.2.4, arm64-v8a + x86_64) green locally; CI green on the superseded PRs (same code). DCO signed (both commits carried it). --------- Signed-off-by: will wade <willwade@gmail.com>
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Stacked on #14 (branches from it; merge #14 first). Implements the Android side of DasherCore #56 / v0.2.4.
What
The engine laid out node labels using a
codepoints × fontSize/2width estimate; the error compounds down the label shunting chain and deep-zoom text degenerates into jumbles (reported making long sentences untypeable on Windows; Android shares the engine path).Wires the new
dasher_set_text_size_callbackend to end:jni_bridge.cpp):textSizeCallbackmarshals into a cachedNativeBridge.onTextSize(String, int, float[]) → booleanmethod — the same pattern as clipboard/speak/message/parameter callbacks. New bindings:nativeSetTextSizeCallback,nativeTextMetricsChanged.DasherCanvasView):measureGlyphTextmeasures with the same Paint the canvas draws opcode-5 text with, including its size transform (engineSize × 2.5, floored at 8) — measuring with the raw font size would desync layout from drawing.glyphFontNamechanges now firenativeTextMetricsChangedso a font switch re-measures.NativeBridgelisteners are static, so the IME must reinstall on everycreateEngine()— otherwise it would inherit the (possibly destroyed) Activity's canvas.Caveat documented in code: the canvas's emergency normalize transform (off-screen/huge-span frames) scales geometry per-frame and can't be known at measurement time; measurement matches the normal (non-normalized) path, which is the steady state.
Submodule: DasherCore → v0.2.4.
Testing
:app:compileDebugKotlin+:app:testDebugUnitTest+:app:assembleDebug(native build vs v0.2.4, arm64-v8a + x86_64) green locally.Sibling wiring: Dasher-GTK #53; Dasher-Windows tracked in #28.
DCO signed.