You can see this when browsing around Amazon with Aggressive Tile Retention on: 1. Go to http://www.amazon.com/Best-Sellers-Video-Games-PlayStation-Hardware/zgbs/videogames/14210751/ 2. Scroll to the bottom. 3. Click on the next page of results. 4. Scroll to the bottom. 5. Move the mouse around. You'll probably see stale content start repainting. <rdar://problem/13520671>
Created attachment 197194 [details] patch
Comment on attachment 197194 [details] patch View in context: https://bugs.webkit.org/attachment.cgi?id=197194&action=review > Source/WebCore/platform/graphics/ca/mac/TileController.mm:736 > + if (it->key.y() < topLeftForBounds.y() > + || it->key.y() > bottomRightForBounds.y() > + || it->key.x() < topLeftForBounds.x() > + || it->key.x() > bottomRightForBounds.x()) Would be cleaner if you copied it->key into a TileIndex variable.
http://trac.webkit.org/changeset/148102