Coverage Buffer Occlusion Culling

[JeffR]

So I spotted this neat little article that goes over utilizing a C-Buffer a la Crytek's method for occlusion culling and as an alternative to straight up Software Occlusion Culling.

Interesting on it's own for sure, but double so in that it uses T3D for his engine of choice:

http://www.gamedev.net/page/resources/_/technical/graphics-programming-and-theory/coverage-buffer-as-main-occlusion-culling-technique-r4103

[Timmy]

Good find :mrgreen: Do take note of what the user raspo says in the comments section (former Crytek guy).

[buckmaster]

Haha awesome. We should probably contact this person and see if they're interested in contributing their code!

[andrewmac]

Neat. I've been pursuing the idea of software occlusion culling for a bit now. I started a library I call SoftOcclude, based on intels work, to accomplish exactly this. Repo Link: https://github.com/andr3wmac/SoftOcclude

In the library, occludees are software rasterized to create a depth buffer completely on the CPU side without stalling the GPU. Then occluders are bounding box rasterized and tested against the depth buffer on the CPU ( same method as his ). Really, the only difference is where you get the depth buffer to test against. It would be trivial to adapt the library to use a supplied depth buffer instead of rasterizing one itself.

If anyone is interested in pursing this on the T3D side, let me know, I can help. I'm working on the library for Torque 6 usage, but it's very universal. Eventually it will be SSE optimized and threaded, which should be able to produce even better numbers than what he's getting, even if you're using the previous frames depth buffer instead of rasterizing a new one.

[JeffR]

@andrewmac

Yeah, I remember you working on the SoftOcclude stuff before. i think it'd definitely be worth further work and eventual integration if possible, as good, fast occlusion can be a pretty huge boon to performance.