From Compiz

This patch will make XGL faster overall, it will make animations more smooth and resizing will be improved.

The Patch

--- xserver/composite/compalloc.c~	2006-12-21 17:31:33.000000000 +0100
+++ xserver/composite/compalloc.c	2006-12-21 17:33:58.000000000 +0100
@@ -486,12 +486,23 @@
 	
 	ValidateGC(&pPixmap->drawable, pGC);
 	dixChangeGC (serverClient, pGC, GCSubwindowMode, &val, NULL);
+	
+	#if 1 /* ugly hack to avoid frame buffer reads */
+	   val = 0;
+	   dixChangeGC (serverClient, pGC, GCForeground, &val, NULL);
+	
+	   {
+	       xRectangle rect = { 0, 0, w, h };
+	       (*pGC->ops->PolyFillRect) (&pPixmap->drawable, pGC, 1, &rect);
+	   }
+	#else 
 	(*pGC->ops->CopyArea) (&pParent->drawable,
 			       &pPixmap->drawable,
 			       pGC,
 			       x - pParent->drawable.x,
 			       y - pParent->drawable.y,
 			       w, h, 0, 0);
+        #endif
 	FreeScratchGC (pGC);
     }
     return pPixmap;

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