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Caustic graphics is a company which claims to have solved most problems related to incoherent memory access when ray-tracing secondary rays (gosh, that’s a sentence, but the claim is even more impressive). While nobody knows so far how they do it, PC Perspective has released an article which explains a bit more what they do. Interesting read, even though I have doubts that this is really the future (which I see in hybrid ray-tracing algorithms, where the ray-tracing is part of the shader execution — and primary rays are still handled by rasterization).
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