nsViewManager :: Refresh

Created explicit pointers to offscreen and onscreen rendering contexts.
Stop passing NS_COPYBITS_TO_BACK_BUFFER flag.

view/src/nsView.cpp

@@ -674,7 +674,7 @@ NS_IMETHODIMP nsView :: Paint(nsIRenderingContext& rc, const nsRect& rect,
               NS_RELEASE(blender);
               NS_RELEASE(dx);
 
-              rc.CopyOffScreenBits(surf, 0, 0, brect, NS_COPYBITS_XFORM_DEST_VALUES | NS_COPYBITS_TO_BACK_BUFFER);
+              rc.CopyOffScreenBits(surf, 0, 0, brect, NS_COPYBITS_XFORM_DEST_VALUES);
             }
 
             rc.DestroyDrawingSurface(surf);

view/src/nsViewManager.cpp

@@ -391,6 +391,10 @@ NS_IMETHODIMP nsViewManager :: ResetScrolling(void)
 void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, nsIRegion *region, PRUint32 aUpdateFlags)
 {
   nsRect              wrect;
+  nsIRenderingContext *onscreencx = nsnull;  // on screen 
+  nsIRenderingContext *offscreencx = nsnull; // secondary buffer
+  // the localcx points to the (offscreencx) if double buffering, 
+  // otherwise it points to (onscreencx)
   nsIRenderingContext *localcx = nsnull;
   nsDrawingSurface    ds = nsnull;
 
@@ -414,13 +418,16 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, nsI
   if (nsnull == aContext)
   {
     localcx = CreateRenderingContext(*aView);
+    onscreencx = localcx;
 
     //couldn't get rendering context. this is ok at init time atleast
     if (nsnull == localcx)
       return;
   }
-  else
+  else {
     localcx = aContext;
+    onscreencx = aContext;
+  }
 
   if (aUpdateFlags & NS_VMREFRESH_DOUBLE_BUFFER)
   {
@@ -432,7 +439,9 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, nsI
     wrect.x = wrect.y = 0;
 
     NS_RELEASE(widget);
-
+ 
+    localcx = CreateRenderingContext(*aView);
+    offscreencx = localcx;
     ds = GetDrawingSurface(*localcx, wrect);
   }
 
@@ -450,13 +459,15 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, nsI
 
   if ((aUpdateFlags & NS_VMREFRESH_DOUBLE_BUFFER) && ds)
 #ifdef NEW_COMPOSITOR
-    localcx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, 0);
+    onscreencx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, 0);
 #else
-    localcx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, NS_COPYBITS_USE_SOURCE_CLIP_REGION);
+    onscreencx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, NS_COPYBITS_USE_SOURCE_CLIP_REGION);
 #endif
 
-  if (localcx != aContext)
-    NS_RELEASE(localcx);
+  if (onscreencx != aContext)
+    NS_RELEASE(onscreencx);
+
+  NS_IF_RELEASE(offscreencx);
 
   // Subtract the area we just painted from the dirty region
   if ((nsnull != region) && !region->IsEmpty())
@@ -478,6 +489,10 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, nsI
 void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, const nsRect *rect, PRUint32 aUpdateFlags)
 {
   nsRect              wrect, brect;
+  nsIRenderingContext *onscreencx = nsnull;  // on screen 
+  nsIRenderingContext *offscreencx = nsnull; // secondary buffer
+  // the localcx points to the (offscreencx) if double buffering, 
+  // otherwise it points to (onscreencx)
   nsIRenderingContext *localcx = nsnull;
   nsDrawingSurface    ds = nsnull;
 
@@ -500,16 +515,20 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, con
     aUpdateFlags &= ~NS_VMREFRESH_DOUBLE_BUFFER;
 #endif
 
+
   if (nsnull == aContext)
   {
     localcx = CreateRenderingContext(*aView);
+    onscreencx = localcx;
 
     //couldn't get rendering context. this is ok if at startup
     if (nsnull == localcx)
       return;
   }
-  else
+  else {
     localcx = aContext;
+    onscreencx = aContext;
+  }
 
   if (aUpdateFlags & NS_VMREFRESH_DOUBLE_BUFFER)
   {
@@ -523,6 +542,9 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, con
 
     NS_RELEASE(widget);
 
+      //Create a new rendering context for the background buffer.
+    localcx = CreateRenderingContext(*aView);
+    offscreencx = localcx;
     ds = GetDrawingSurface(*localcx, wrect);
   }
 
@@ -538,21 +560,24 @@ void nsViewManager :: Refresh(nsIView *aView, nsIRenderingContext *aContext, con
 #ifdef NEW_COMPOSITOR
   {
 #ifdef XP_MAC
-    localcx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, 0);
+    onscreencx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, 0);
 #else
 #ifdef XP_UNIX
-    localcx->SetClipRect(trect, nsClipCombine_kReplace, result);
+    onscreencx->SetClipRect(trect, nsClipCombine_kReplace, result);
 #endif //unix
-    localcx->CopyOffScreenBits(ds, brect.x, brect.y, brect, 0);
+    onscreencx->CopyOffScreenBits(ds, brect.x, brect.y, brect, 0);
 #endif //mac
   }
 #else
-    localcx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, NS_COPYBITS_USE_SOURCE_CLIP_REGION);
+    onscreencx->CopyOffScreenBits(ds, wrect.x, wrect.y, wrect, NS_COPYBITS_USE_SOURCE_CLIP_REGION);
 #endif
 
 
-  if (localcx != aContext)
-    NS_RELEASE(localcx);
+  if (onscreencx != aContext)
+    NS_RELEASE(onscreencx);
+
+  NS_IF_RELEASE(offscreencx);
+
 
   // Subtract the area we just painted from the dirty region
   nsIRegion *dirtyRegion;
@@ -1082,7 +1107,7 @@ void nsViewManager :: RenderViews(nsIView *aRootView, nsIRenderingContext& aRC,
             mBlueCX->Translate(localrect.x, localrect.y);
 
             //buffer swap.
-            aRC.CopyOffScreenBits(gOffScreen, 0, 0, localrect, NS_COPYBITS_XFORM_DEST_VALUES | NS_COPYBITS_TO_BACK_BUFFER);
+            aRC.CopyOffScreenBits(gOffScreen, 0, 0, localrect, NS_COPYBITS_XFORM_DEST_VALUES);
           }
           else
           {