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[Ivan]

Post them if you got them.

[Will Vale]

I don't have any resources but I have used this technique for a couple of things, so if you have any specific questions I might be able to help

[mcc]

I don't know if this is the appropriate place to talk about this, but something that drives me absolutely nuts is polygon sorting in the presence of polygons with alpha.

Like maybe I know how to go about sorting my draws front-to-back, but if there's a chance something semitransparent might get drawn, then you need to go back-to-front...

Could a smart occlusion culling type system work around this?

[Will Vale]

Sorting for alpha is annoying The simplest solution is to go in two steps:

1) Draw large opaque objects front to back (for good Z rejection performance)

1.5) (optionally) Draw skybox (saves shading a lot of pixels)

2) Draw alpha objects back to front.

I remember also getting decent results just drawing back to front, with alpha surfaces in a model (like windshields) statically sorted to the end of that particular model. Not quite so good for performance but nice and simple.

Cheers,

Will

[Zaphos]

There's a post on optimizations related to alpha sorting on christer ericson's blog: http://realtimecollisiondetection.net/blog/?p=91

Also here is an occlusion culling link about using it for pixel perfect collision detection ... probably not what anyone was looking for ... http://blogs.msdn.com/shawnhar/archive/2008/12/31/pixel-perfect-collision-detection-using-gpu-occlusion-queries.aspx