[gtk+/client-side-windows: 262/284] Remove invalid source area from copy in move_region_on_impl

[Alexander Larsson <alexl src gnome org>]

commit 51010ca066dd3b3683d47936b9d1304753ddd7df
Author: Alexander Larsson <alexl redhat com>
Date:   Sun Feb 8 13:35:17 2009 +0100

    Remove invalid source area from copy in move_region_on_impl
    
    There is no need to copy something that is already invalid and will
    be marked as invalid in the destination anyway, so we remove this
    area from the region to copy.
---
 gdk/gdkwindow.c |   34 +++++++++++++++++++---------------
 1 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index bef015f..f87ed97 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -2571,7 +2571,8 @@ append_move_region (GdkWindowObject *impl_window,
     g_list_append (impl_window->outstanding_moves, move);
 }
 
-/* Moves bits and update area by dx/dy in impl window */
+/* Moves bits and update area by dx/dy in impl window,
+   takes ownership of region */
 static void
 move_region_on_impl (GdkWindowObject *private,
 		     GdkRegion *region, /* In impl window coords */
@@ -2585,18 +2586,12 @@ move_region_on_impl (GdkWindowObject *private,
   
   impl_window = gdk_window_get_impl_window (private);
 
-  if (1) /* Enable flicker free handling of moves. */
-    append_move_region (impl_window, region, dx, dy);
-  else
-    do_move_region_bits_on_impl (impl_window,
-				 region, dx, dy);
-    
   /* Move any old invalid regions in the copy source area by dx/dy */
   if (impl_window->update_area)
     {
       GdkRegion *update_area;
-      
       update_area = gdk_region_copy (region);
+      
       /* Convert from target to source */
       gdk_region_offset (update_area, -dx, -dy);
       gdk_region_intersect (update_area, impl_window->update_area);
@@ -2605,8 +2600,21 @@ move_region_on_impl (GdkWindowObject *private,
       /* Convert back */
       gdk_region_offset (update_area, dx, dy);
       gdk_region_union (impl_window->update_area, update_area);
+
+      /* This area of the destination is now invalid,
+	 so no need to copy to it.  */
+      gdk_region_subtract (region, update_area);
+      
       gdk_region_destroy (update_area);
     }
+  
+  if (1) /* Enable flicker free handling of moves. */
+    append_move_region (impl_window, region, dx, dy);
+  else
+    do_move_region_bits_on_impl (impl_window,
+				 region, dx, dy);
+    
+  gdk_region_destroy (region);
 }
 
 /* Flushes all outstanding changes to the window, call this
@@ -6206,7 +6214,7 @@ gdk_window_move_resize_internal (GdkWindow *window,
       /* convert from parent coords to impl */
       gdk_region_offset (copy_area, private->abs_x - private->x, private->abs_y - private->y);
 
-      move_region_on_impl (impl_window, copy_area, dx, dy);
+      move_region_on_impl (impl_window, copy_area, dx, dy); /* takes ownership of copy_area */
 
       /* Invalidate affected part in the parent window
        *  (no higher window should be affected)
@@ -6217,7 +6225,6 @@ gdk_window_move_resize_internal (GdkWindow *window,
 
       gdk_region_destroy (old_region);
       gdk_region_destroy (new_region);
-      gdk_region_destroy (copy_area);
     }
 
   if (old_native_child_region)
@@ -6402,12 +6409,11 @@ gdk_window_scroll (GdkWindow *window,
   /* convert from window coords to impl */
   gdk_region_offset (copy_area, private->abs_x, private->abs_y);
 
-  move_region_on_impl (impl_window, copy_area, dx, dy);
+  move_region_on_impl (impl_window, copy_area, dx, dy); /* takes ownership of copy_area */
    
   /* Invalidate not copied regions */
   gdk_window_invalidate_region (window, noncopy_area, TRUE);
 
-  gdk_region_destroy (copy_area);
   gdk_region_destroy (noncopy_area);
 
   if (old_native_child_region)
@@ -6474,9 +6480,7 @@ gdk_window_move_region (GdkWindow       *window,
   /* convert from window coords to impl */
   gdk_region_offset (copy_area, private->abs_x, private->abs_y);
   
-  move_region_on_impl (impl_window, copy_area, dx, dy);
-
-  gdk_region_destroy (copy_area);
+  move_region_on_impl (impl_window, copy_area, dx, dy); /* Takes ownership of copy_area */
 }
 
 /**