Fix MV Scene_Boot hang: measureText was font-agnostic, breaking Graphics.isFontLoaded - #1152
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…ics.isFontLoaded MV's classic font-ready check (Scene_Boot.isGameFontLoaded, via Graphics.isFontLoaded) measures '40px GameFont, sans-serif' against '40px sans-serif' and waits for the two widths to diverge. Our measureText (mruby-mvjs/src/mvcanvas.cxx) backed every font shorthand with the same loaded game font regardless of the requested family, so those two measurements were always identical and the check never passed -- Scene_Boot would hang until its own 20s timeout and throw "Error: Failed to load GameFont", on any project whose corescript takes this path rather than the newer FontFaceSet path our document.fonts stand-in already covers. Found against a real, downloaded RPG Maker MV release (an Enigma Virtual Box-packed single-file distributable, unpacked with evbunpack to reach its www/ project) that never got past Scene_Boot. Fixed by having measureText/fillText/strokeText parse whether the font shorthand actually names "GameFont" and route anything else through the same rough per-character estimate already used when no game font is loaded at all -- guaranteed to differ from the real metrics. Verified: the same real game now reaches Scene_Title, New Game and Scene_Map. data/Lunatic-Core and data/mv-sample both happen to use a corescript build that takes the FontFaceSet path already, which is why this stayed hidden until a different real release exercised the older one. Adds a regression test in mruby-mvjs/test/canvas_test.rb (asserts the exact fallback value for a non-"GameFont" shorthand, independent of whether a real font happens to be loaded in the test environment) and documents the root cause in docs/TODO.md's M5 section. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01RmARb1uB2F9rXRg6tQsGgR
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CI's clang-format pre-commit hook reflows the font_text_width signature and a comment block differently than my by-hand wrapping. Reformatted to the tool's own output (verified locally: clang-format -i now produces no diff). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01RmARb1uB2F9rXRg6tQsGgR
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Summary
Scene_Boot.isGameFontLoaded, viaGraphics.isFontLoaded) measures'40px GameFont, sans-serif'against'40px sans-serif'and waits for the two widths to diverge. OurmeasureText(mruby-mvjs/src/mvcanvas.cxx) backed every font shorthand with the same loaded game font regardless of the requested family, so those two measurements were always identical and the check never passed —Scene_Bootwould hang until its own 20s timeout and throwError: Failed to load GameFont, on any project whose corescript takes this path rather than the newer FontFaceSet path ourdocument.fontsstand-in already covers.evbunpackto reach itswww/project) that never got pastScene_Boot.measureText/fillText/strokeTextparse whether the font shorthand actually names"GameFont"and route anything else through the same rough per-character estimate already used when no game font is loaded at all — guaranteed to differ from the real metrics.data/Lunatic-Coreanddata/mv-sampleboth happen to use a corescript build that takes the FontFaceSet path already, which is why this stayed hidden until a different real release exercised the older one.Test plan
Scene_Boot → Scene_Title → New Game → Scene_Map(previously stuck atScene_Bootforever)rake test(mrbtest): 1842 OK, 0 KO, 0 Crash — includes a new regression test inmruby-mvjs/test/canvas_test.rbthat asserts the exact fallback value for a non-"GameFont"shorthand, independent of whether a real font happens to be loaded in the test environmentLunatic-Coreandmz-sample: all still green, no regressions🤖 Generated with Claude Code
https://claude.ai/code/session_01RmARb1uB2F9rXRg6tQsGgR
Generated by Claude Code