A Blag About Graphics and Programming

Somehow managed to get virtual depth cube maps to work. No fetch4, no fancy filtering, simply render to a D3DFMT_D24X8 texture and automagically get the shadowing term with a tex2Dproj().
The results:
Simple D3DFMT_R32F cubemap: 64fps;
Virtual D3DFMT_R32F cubemap: 62fps;
Virtual depth cube map: 69fps;

I think I'm doing the double-speed Z rendering, but on the other hand, the final pixel shader is more complicated, I guess that's why the performance increase is so small.
One interesting thing, my ATI hd2600 does perform some kind of shadow filtering when Linear filtering is enabled for the depth map. So you get a bit of speed and a bit better image quality.
The annoying thing is that even though you are rendering only to the depth buffer, you still need a color buffer which is the same size as the depth buffer (in my case- 1536x1024).


And here's the performance on my gf6200:
Simple D3DFMT_R32F cubemap: 17fps;
Virtual D3DFMT_R32F cubemap: 16fps;
Virtual depth cube map: 16fps;
Impressive

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