openlayers/openlayers — pull request #702 by ahocevar (2012-10-04 18:21:50+00:00)
Title: Tile image cache and tile queue improvements

We now reuse tile images by maintaining a cache of image elements with a
LRU expiry policy. The tile queue is bypassed for images that are available
in the cache, so they can be rendered immediately. And the tile queue
itself loads more than just one image at a time now.

Performance improvements are achieved by using requestAnimationFrame when
a tile's visibility changes, and by not starting with a blank image when
creating a new tile image. It seems that even Firefox does not show a
loading placeholder when the tile is made visible in an animation.