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Comment by mattnewport | Hacker News Reader

I'm not convinced the part of ray tracing implemented in hardware on the new NVidia cards (primarily bvh traversal and ray triangle intersection) is significantly more complex than things that are already implemented in hardware (rasterization, anisotropic filtering, tesselation, scheduling, compression, etc.) and those tend to be pretty solid.

I also expect the hardware ray tracing to be heavily used for offline rendering before it becomes mainstream for real time so there will be plenty of usage from demanding customers to iron out any issues.

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It's true that features of similar or greater complexity do tend to work pretty well already, but those features tend to be the ones that are practically fundamental and used everywhere. (edit: but I have hit bugs with scheduling too- and maybe tessellation and anisotropic filtering, but those cases were weird enough where it was hard to tease out the true cause.)

Ray tracing has a good shot at getting there (and probably in less than 5-10 years), and developers who can afford the suffering will hopefully pave the way, but early adopters should be very wary.

To be clear, I'm not catastrophically pessimistic. I intend to do some work with it, but I'm not under any illusions. I once encountered five distinct blocking driver bugs in the span of a single week. I just assume everything is broken until proven otherwise.

I think drivers tend to be more problematic than hardware, I'd actually expect more issues with driver implemented support for ray tracing APIs running as compute shaders than with the hardware accelerated support.

Yup, that's definitely true. It's going to be a fun transition period.

> primarily bvh traversal and ray triangle intersection

I've been waiting for a concise explanation of that the damn hardware on these cards actually does since the release announcement. Thank-you.

So meshes are still pivotal. I was hoping for something that might lend itself to accelerating rendering of other types of object representation.

You can write your own custom intersection shaders to support other types of geometry but they will run using the regular compute hardware rather than with the dedicated hardware for the ray triangle intersection. I believe they will still benefit from the bvh traversal hardware.

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