backport bug #3332 (win32 deadkeys) patch:

https://bugzilla.libsdl.org/show_bug.cgi?id=3332 Eric Wasylishen <ewasylishen@gmail.com>
libsdl-org · Mar 24, 2018 · d70a3a6 · d70a3a6
1 parent 2743d4e
commit d70a3a6
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diff --git a/src/events/SDL_keyboard.c b/src/events/SDL_keyboard.c
@@ -334,8 +334,16 @@ int SDL_KeyboardInit(void)
 	/* Done.  Whew. */
 	return(0);
 }
+
+#ifdef _WIN32
+extern void WIN_ResetDeadKeys(void);
+#endif
+
 void SDL_KeyboardQuit(void)
 {
+#ifdef _WIN32
+	WIN_ResetDeadKeys();
+#endif
 }
 
 /* We lost the keyboard, so post key up messages for all pressed keys */
@@ -362,6 +370,11 @@ int SDL_EnableUNICODE(int enable)
 	if ( enable >= 0 ) {
 		SDL_TranslateUNICODE = enable;
 	}
+#ifdef _WIN32
+	if (enable != old_mode) {
+		WIN_ResetDeadKeys();
+	}
+#endif
 	return(old_mode);
 }
 

diff --git a/src/video/windib/SDL_dibevents.c b/src/video/windib/SDL_dibevents.c
@@ -583,6 +583,37 @@ static int SDL_MapVirtualKey(int scancode, int vkey)
 	return mvke?mvke:vkey;
 }
 
+#ifndef MAPVK_VK_TO_VSC
+#define MAPVK_VK_TO_VSC 0
+#endif
+void
+WIN_ResetDeadKeys(void)
+{
+    /*
+    if a deadkey has been typed, but not the next character (which the deadkey might modify),
+    this tries to undo the effect pressing the deadkey.
+    see: http://archives.miloush.net/michkap/archive/2006/09/10/748775.html
+    */
+    BYTE keyboardState[256];
+    WCHAR buffer[16];
+    UINT keycode, scancode, i;
+    int result;
+
+    GetKeyboardState(keyboardState);
+    keycode = VK_SPACE;
+    scancode = MapVirtualKey(keycode, MAPVK_VK_TO_VSC);
+    if (scancode == 0) {
+        return; /* the keyboard doesn't have this key */
+    }
+
+    for (i = 0; i < 5; i++) {
+        result = SDL_ToUnicode(keycode, scancode, keyboardState, (LPWSTR)buffer, 16, 0);
+        if (result > 0) {
+            return; /* success */
+        }
+    }
+}
+
 static SDL_keysym *TranslateKey(WPARAM vkey, UINT scancode, SDL_keysym *keysym, int pressed)
 {
 	/* Set the keysym information */