Fix SDL_TEXTINPUT ignoring Shift/Caps Lock for letter keys#742
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The TEXTINPUT event generated in generateKeyEvent() uses the raw SDL keycode (`keysym.sym & 0xff`) as the text character. For letter keys a-z, this always produces the lowercase character regardless of whether Shift or Caps Lock is active. Real SDL2 generates TEXTINPUT through the OS input method, which applies modifier state to produce the correct case. Games that derive character input from SDL_TEXTINPUT (e.g. ScummVM's obtainUnicode() which peeks the event queue for TEXTINPUT before falling back to the Shift-based mapKey() path) receive the wrong character for Shift+letter / Caps+letter combinations. The fix checks keysym.mod (already correctly populated by xkeyboardToSDLMod since commit 5deef26) for KMOD_SHIFT or KMOD_CAPS, and applies the standard uppercase transformation (c &= ~0x20) to letters a-z before writing the TEXTINPUT text. This is complementary to issue clementgallet#405 (Shift+Click) — that fix addressed the mod field on SDL_KEYDOWN events; this addresses the text content of SDL_TEXTINPUT events, which is a separate code path. Only ASCII letters are handled; non-letter shifted characters (Shift+1 → '!') would require a full keyboard layout lookup and are left for a future change.
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Summary
generateKeyEvent()ininputevents.cppgeneratesSDL_TEXTINPUTevents using the raw SDL keycode (keysym.sym & 0xff), which always produces lowercase for letter keys regardless of modifier state. Real SDL2 generates TEXTINPUT through the OS input method, which applies Shift/Caps Lock.This breaks games that derive character input from
SDL_TEXTINPUTrather than fromSDL_KEYDOWN+ modifier flags — for example, ScummVM'sobtainUnicode()peeks the event queue for TEXTINPUT and uses it directly, bypassing its own Shift→uppercase fallback path.Fix
When
keysym.modhasKMOD_SHIFTorKMOD_CAPSset, applyc &= ~0x20to letters a–z before writing the TEXTINPUT text. This matches real SDL2 behavior for ASCII letters.Only letters are handled; non-letter shifted characters (e.g. Shift+1 →
!) would require a keyboard layout lookup and are left for a future change.Relation to #405
Issue #405 (Shift+Click) was fixed by commits
5deef26(mod field on SDL_KEYDOWN) and422018a(X11/XCB modifier state). Those fixes address modifier flags on key events — this PR addresses the text content ofSDL_TEXTINPUTevents, which is a separate code path that the earlier fixes don't reach.