--- a/gfx/layers/opengl/ThebesLayerOGL.cpp
+++ b/gfx/layers/opengl/ThebesLayerOGL.cpp
@@ -111,16 +111,17 @@ public:
   nsIntSize GetSize() {
     if (mTexImage)
       return mTexImage->GetSize();
     return nsIntSize(0, 0);
   }
 
 protected:
   virtual nsIntPoint GetOriginOffset() = 0;
+  virtual nsIntRect GetBufferRect() = 0;
 
   GLContext* gl() const { return mOGLLayer->gl(); }
 
   ThebesLayer* mLayer;
   LayerOGL* mOGLLayer;
   nsRefPtr<TextureImage> mTexImage;
   nsRefPtr<TextureImage> mTexImageOnWhite;
 };
@@ -192,45 +193,45 @@ ThebesLayerBufferOGL::RenderTo(const nsI
     }
 
     mTexImage->BeginTileIteration();
     if (mTexImageOnWhite) {
       mTexImageOnWhite->BeginTileIteration();
       NS_ASSERTION(mTexImageOnWhite->GetTileRect() == mTexImage->GetTileRect(), "component alpha textures should be the same size.");
     }
     nsIntRegion region(*renderRegion);
+
     nsIntPoint origin = GetOriginOffset();
-    region.MoveBy(-origin);           // translate into TexImage space, buffer origin might not be at texture (0,0)
-
     do {
       nsIntRect textureRect = mTexImage->GetTileRect();
-      textureRect.MoveBy(region.GetBounds().x, region.GetBounds().y);
       nsIntRegion subregion(region);
-      subregion.And(region, textureRect); // region this texture is visible in
+      textureRect.MoveBy(GetBufferRect().TopLeft());
+      subregion.And(subregion, textureRect); // region this texture is visible in
       if (subregion.IsEmpty()) {
         continue;
       }
       // Bind textures.
       TextureImage::ScopedBindTexture texBind(mTexImage, LOCAL_GL_TEXTURE0);
       TextureImage::ScopedBindTexture texOnWhiteBind(mTexImageOnWhite, LOCAL_GL_TEXTURE1);
 
       nsIntRegionRectIterator iter(subregion);
       while (const nsIntRect *iterRect = iter.Next()) {
-        nsIntRect regionRect = *iterRect;  // one rectangle of this texture's region
-        // translate into the correct place for this texture sub-region
-        nsIntRect screenRect = regionRect;
-        screenRect.MoveBy(origin);
+        nsIntRect screenRect = *iterRect;
         program->SetLayerQuadRect(screenRect);
 
-        regionRect.MoveBy(-mTexImage->GetTileRect().TopLeft()); // get region of tile
-        aManager->BindAndDrawQuadWithTextureRect(program, regionRect,
+        nsIntRect textureCoord = *iterRect;  // one rectangle of this texture's region
+        textureCoord.MoveBy(-mTexImage->GetTileRect().TopLeft()); // get region of tile
+        textureCoord.MoveBy(-origin); // get region of tile
+
+        aManager->BindAndDrawQuadWithTextureRect(program, textureCoord,
                                                  textureRect.Size(),
                                                  mTexImage->GetWrapMode());
       }
     } while (mTexImage->NextTile());
+
   }
 
   if (mTexImageOnWhite) {
     // Restore defaults
     gl()->fBlendFuncSeparate(LOCAL_GL_ONE, LOCAL_GL_ONE_MINUS_SRC_ALPHA,
                              LOCAL_GL_ONE, LOCAL_GL_ONE);
   }
 }
@@ -268,16 +269,20 @@ public:
   {
     NS_ASSERTION(gfxASurface::CONTENT_ALPHA != aType,"ThebesBuffer has color");
 
     mTexImage = CreateClampOrRepeatTextureImage(gl(), aSize, aType, aFlags);
     return mTexImage ? mTexImage->GetBackingSurface() : nsnull;
   }
 
 protected:
+  virtual nsIntRect GetBufferRect() {
+    return BufferRect();
+  }
+
   virtual nsIntPoint GetOriginOffset() {
     return BufferRect().TopLeft() - BufferRotation();
   }
 };
 
 
 // This implementation is (currently) the slow-path for when we can't
 // implement pixel retaining using thebes.  This implementation and
@@ -300,16 +305,20 @@ protected:
   enum XSide {
     LEFT, RIGHT
   };
   enum YSide {
     TOP, BOTTOM
   };
   nsIntRect GetQuadrantRectangle(XSide aXSide, YSide aYSide);
 
+  virtual nsIntRect GetBufferRect() {
+    return mBufferRect;
+  }
+
   virtual nsIntPoint GetOriginOffset() {
     return mBufferRect.TopLeft() - mBufferRotation;
   }
 
 private:
   nsIntRect mBufferRect;
   nsIntPoint mBufferRotation;
 };
@@ -759,16 +768,20 @@ public:
     NS_RUNTIMEABORT("can't BeginPaint for a shadow layer");
     return PaintState();
   }
 
   void Upload(gfxASurface* aUpdate, const nsIntRegion& aUpdated,
               const nsIntRect& aRect, const nsIntPoint& aRotation);
 
 protected:
+  virtual nsIntRect GetBufferRect() {
+    return mBufferRect;
+  }
+
   virtual nsIntPoint GetOriginOffset() {
     return mBufferRect.TopLeft() - mBufferRotation;
   }
 
 private:
   nsIntRect mBufferRect;
   nsIntPoint mBufferRotation;
 };