Metacity changes to paint ARGB window titles correctly

[Keith Packard <keithp keithp com>]

For those of you who've tried them, Metacity generates some "interesting" 
images on the screen when painting the frame for an ARGB window.

I discovered the root cause and have kludged a partial fix.

The basic problem is that Metacity shares one single "widget" to hold the 
style for every frame.  A cheap hack, which works as long as every frame 
uses the same visual and colormap, which of course they do except for ARGB 
windows.

I think the correct solution is to give each frame its own style using 
gtk_style_attach from the shared frames style.

However, the problem is that the theme drawing code all passes around the 
frames widget as a handle to the style and (separately) the GdkDrawable 
representing the individual frame itself.

Instead of rewriting all of the drawing code, I kludged things by 
replacing the style in the shared frames widget with the frame's style.  
This actually worked, but it sure looks wrong in the code.

Here's the patches; I sent necessary fixes for gdk to gtk-devel-list.
This patch is almost certainly missing code necessary to get the per-frame 
styles updated when the shared frames style is changed.  I fear attempting 
that though.

-keith

? changes
Index: src/compositor.c
===================================================================
RCS file: /cvs/gnome/metacity/src/compositor.c,v
retrieving revision 1.8
diff -u -r1.8 compositor.c
--- src/compositor.c	26 Dec 2003 02:42:38 -0000	1.8
+++ src/compositor.c	18 Jun 2004 23:09:38 -0000
@@ -194,7 +194,11 @@
   if (!(compositor->have_composite &&
         compositor->have_fixes &&
         compositor->have_render &&
-        compositor->have_damage))
+        compositor->have_damage &&
+#ifndef ENABLE_COMPOSITOR
+	0
+#endif
+	))
     {
       meta_topic (META_DEBUG_COMPOSITOR, "Failed to find all extensions needed for compositing manager, disabling compositing manager\n");
       g_assert (!compositor->enabled);
Index: src/frames.c
===================================================================
RCS file: /cvs/gnome/metacity/src/frames.c,v
retrieving revision 1.75
diff -u -r1.75 frames.c
--- src/frames.c	24 Nov 2003 18:09:47 -0000	1.75
+++ src/frames.c	18 Jun 2004 23:09:38 -0000
@@ -270,7 +270,7 @@
    * resize may not actually be needed so we always redraw
    * in case of color change.
    */
-  gtk_style_set_background (GTK_WIDGET (frames)->style,
+  gtk_style_set_background (frame->style,
                             frame->window, GTK_STATE_NORMAL);
   gdk_window_invalidate_rect (frame->window, NULL, FALSE);
   meta_core_queue_frame_resize (gdk_display,
@@ -315,7 +315,7 @@
    * resize may not actually be needed so we always redraw
    * in case of color change.
    */
-  gtk_style_set_background (GTK_WIDGET (frames)->style,
+  gtk_style_set_background (frame->style,
                             frame->window, GTK_STATE_NORMAL);
   gdk_window_invalidate_rect (frame->window, NULL, FALSE);
 }
@@ -476,12 +476,13 @@
   
   frame->window = window;
 
+  frame->style = gtk_style_attach (GTK_WIDGET(frames)->style, frame->window);
+  
   gdk_window_set_user_data (frame->window, frames);
-  gtk_style_set_background (GTK_WIDGET (frames)->style,
+  gtk_style_set_background (frame->style,
 			    frame->window, GTK_STATE_NORMAL);
 
   /* Don't set event mask here, it's in frame.c */
-  
   frame->xwindow = xwindow;
   frame->cache_style = NULL;
   frame->layout = NULL;
@@ -613,7 +614,7 @@
 
   frame = meta_frames_lookup_window (frames, xwindow);
   
-  gtk_style_set_background (widget->style, frame->window, GTK_STATE_NORMAL);
+  gtk_style_set_background (frame->style, frame->window, GTK_STATE_NORMAL);
 }
 
 static void
@@ -1734,9 +1735,14 @@
   int screen_width, screen_height;
   MetaButtonLayout button_layout;
   MetaGrabOp grab_op;
+
+  GtkStyle *save_style;
   
   widget = GTK_WIDGET (frames);
 
+  save_style = widget->style;
+  widget->style = frame->style;
+
   i = 0;
   while (i < META_BUTTON_TYPE_LAST)
     {
@@ -1888,6 +1894,8 @@
       
       ++i;
     }
+
+  widget->style = save_style;
 
   gdk_region_destroy (edges);
   g_free (areas);
Index: src/frames.h
===================================================================
RCS file: /cvs/gnome/metacity/src/frames.h,v
retrieving revision 1.27
diff -u -r1.27 frames.h
--- src/frames.h	16 Aug 2003 16:32:10 -0000	1.27
+++ src/frames.h	18 Jun 2004 23:09:38 -0000
@@ -67,6 +67,8 @@
 {
   Window xwindow;
   GdkWindow *window;
+  GtkStyle *style;
+  /* style of frame */
   MetaFrameStyle *cache_style;
   PangoLayout *layout;
   int text_height;
Index: src/ui.c
===================================================================
RCS file: /cvs/gnome/metacity/src/ui.c,v
retrieving revision 1.56
diff -u -r1.56 ui.c
--- src/ui.c	10 Jan 2004 17:16:07 -0000	1.56
+++ src/ui.c	18 Jun 2004 23:09:39 -0000
@@ -183,7 +183,7 @@
   gint attributes_mask;
   GdkWindow *window;
   GdkVisual *visual;
-  GdkColormap *cmap = gdk_screen_get_default_colormap (screen);
+  GdkColormap *cmap;
   
   /* Default depth/visual handles clients with weird visuals; they can
    * always be children of the root depth/visual obviously, but
@@ -191,13 +191,16 @@
    * visual as the client.
    */
   if (!xvisual)
+  {
     visual = gdk_screen_get_system_visual (screen);
+    cmap = gdk_colormap_ref (gdk_screen_get_default_colormap (screen));
+  }
   else
-    {
-      visual = gdk_x11_screen_lookup_visual (screen,
-                                             XVisualIDFromVisual (xvisual));
-      cmap = gdk_colormap_new (visual, FALSE);
-    }
+  {
+    visual = gdk_x11_screen_lookup_visual (screen,
+					   XVisualIDFromVisual (xvisual));
+    cmap = gdk_colormap_new (visual, FALSE);
+  }
 
   attrs.title = NULL;
 
@@ -224,6 +227,8 @@
   window =
     gdk_window_new (gdk_screen_get_root_window(screen),
 		    &attrs, attributes_mask);
+
+  g_object_unref (cmap);
 
   gdk_window_resize (window, width, height);

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