TIP#171 implementation - sanity for <MouseWheel> event handling!

3 files changed, 28 insertions, 16 deletions

diff --git a/ChangeLog b/ChangeLog
index 7295f6b..67c6f3f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2008-12-28  Donal K. Fellows  <dkf@users.sf.net>
 
+	TIP #171 IMPLEMENTATION
+
+	* win/tkWinX.c (GenerateXEvent): Redirect <MouseWheel> to the window
+	that contains the mouse.
+	* generic/tkEvent.c (InvokeFocusHandlers): Do not direct <MouseWheel>
+	through the focus mechanism.
+
 	* generic/tkImgPNG.c (ReadIDAT): Corrected code to transfer blocks of
 	compressed data into the Tcl_ZlibStream. Allows the reading of all
 	images from PngSuite set. Thanks to Michael Kirkham for fix/testing.
diff --git a/generic/tkEvent.c b/generic/tkEvent.c
index e3f925d..13e1304 100644
--- a/generic/tkEvent.c
+++ b/generic/tkEvent.c
@@ -12,7 +12,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tkEvent.c,v 1.37 2008/11/08 18:44:39 dkf Exp $
+ * RCS: @(#) $Id: tkEvent.c,v 1.38 2008/12/28 22:59:47 dkf Exp $
  */
 
 #include "tkInt.h"
@@ -247,16 +247,10 @@ InvokeFocusHandlers(
     }
 
     /*
-     * MouseWheel events are not focus specific on Mac OS X.
+     * Only key-related events are directed according to the focus.
      */
 
-#ifdef MAC_OSX_TK
-#define FOCUS_DIRECTED_EVENT_MASK (KeyPressMask|KeyReleaseMask)
-#else
-#define	FOCUS_DIRECTED_EVENT_MASK (KeyPressMask|KeyReleaseMask|MouseWheelMask)
-#endif
-
-    if (mask & FOCUS_DIRECTED_EVENT_MASK) {
+    if (mask & (KeyPressMask|KeyReleaseMask)) {
 	(*winPtrPtr)->dispPtr->lastEventTime = eventPtr->xkey.time;
 	*winPtrPtr = TkFocusKeyEvent(*winPtrPtr, eventPtr);
 	if (*winPtrPtr == NULL) {
diff --git a/win/tkWinX.c b/win/tkWinX.c
index 160e141..4609a94 100644
--- a/win/tkWinX.c
+++ b/win/tkWinX.c
@@ -10,7 +10,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tkWinX.c,v 1.59 2008/12/10 05:02:52 das Exp $
+ * RCS: @(#) $Id: tkWinX.c,v 1.60 2008/12/28 22:59:47 dkf Exp $
  */
 
 /*
@@ -1006,10 +1006,26 @@ GenerateXEvent(
     LPARAM lParam)
 {
     XEvent event;
-    TkWindow *winPtr = (TkWindow *)Tk_HWNDToWindow(hwnd);
+    TkWindow *winPtr;
     ThreadSpecificData *tsdPtr = (ThreadSpecificData *)
 	    Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData));
 
+    if (message == WM_MOUSEWHEEL) {
+	POINTS rootPoint = MAKEPOINTS(lParam);
+	POINT pos;
+
+	/*
+	 * Redirect mousewheel events to the window containing the cursor.
+	 * That feels much less strange to users, and is how all the other
+	 * platforms work.
+	 */
+
+	pos.x = rootPoint.x;
+	pos.y = rootPoint.y;
+	hwnd = WindowFromPoint(pos);
+    }
+
+    winPtr = (TkWindow *) Tk_HWNDToWindow(hwnd);
     if (!winPtr || winPtr->window == None) {
 	return;
     }
@@ -1107,11 +1123,6 @@ GenerateXEvent(
 	break;
 
     case WM_MOUSEWHEEL:
-	/*
-	 * The mouse wheel event is closer to a key event than a mouse event
-	 * in that the message is sent to the window that has focus.
-	 */
-
     case WM_CHAR:
     case WM_UNICHAR:
     case WM_SYSKEYDOWN: