Comment 20 for bug 865006

I'm not quite sure if this is related to the bug - but where is transparency calculated? On the CPU or GPU?

Too me the transparency update behaviour reminds me of the pre-compiz days fake transparency seen in Eterm, or aterm.

I even think it's hard to encounter this bug if the transparency is calculated on the GPU, because you'd need to "keep" an old texture, for transparency you usually don't for being a trivial operation on the GPU, so you avoid caching and just recalculate every frame.

I guess you would only cache it if you use the CPU for calculating transparency. But that's not a good idea, right?

However, I think the update-behaviour should be in sync with the compiz refresh cycles, because the idea must be "every frame is perfect".