Posted by gouessej on Dec 31, 2013; 9:25am
URL: https://forum.jogamp.org/picking-tp4031052p4031092.html

ul wrote

You claim that doing things on the GPU cannot be faster than doing it on the CPU. Of course it can! That's why we've had dedicated graphics hardware for a long time and that's why these cards are now being opened up to make their massive parallelism available for general computing.

For a so rudimentary operation (a ray triangle intersection test), I'm not sure it is really faster when done in a shader but if you succeed to split the job correctly to really benefit of parallelism, why not?

ul wrote

So with all due respect, if you want to claim superiority of your oldfashioned hierarchical "software" approach of yesteryear the burden of proof is on you. I'm not going to waste any time with this lost cause. Good luck.

I don't understand your claim. Bounding volumes and hierarchical methods have nothing to do with the "software" approach. I remind you that hierarchical occlusion culling and geometry shaders can be used to compute shadow volumes:
http://http.developer.nvidia.com/GPUGems3/gpugems3_ch11.html
This example uses a binary bounding-volume hierarchy (BVH) of axis-aligned bounding boxes (AABBs). Moreover, occlusion culling, backface culling and frustum culling (with BVH) can be used with deferred shading:
http://gamedev.stackexchange.com/a/66284
How is it old fashioned?

ul wrote

I've understood that you prefer to discuss your pet ideas but my interest in this really is just the OpenGL porting issue. Thanks.

But some people here gave you some pieces of information about the way you could implement that:
- tessellation shaders
- transform feedback
- discard rasterization
- maybe use the primitive id