Flash deals with this issue by cacheing any object that has a complex filter (like a drop shadow) applied to it as a bitmap. This works pretty well, but can lea

Flash deals with this issue by cacheing any object that has a complex filter (like a drop shadow) applied to it as a bitmap. This works pretty well, but can lead to serious memory hogging. Effects like drop-shadows and blurs are notoriously CPU-intensive (and we don't even have arbitrarily-shaped drop shadows yet!). There's no way to do them very effectively without moving onto the GPU. Hopefully that'll happen soon. Or the CSS filters spec gets broad support, in which case there will be a built-in drop-shadow shader.