[OtherShrezzing]

I don’t think the authors are being wilfully deceptive in any way, but Blender Cycles on a gpu of that quality could absolutely render every scene in this paper in less than 4s per frame. There are very modest tech demo scenes with low complexity, and they’ve set blender to cycle through 4k iterations per pixel - which seems non-sensible as Blender would hit something close to its output after a couple of hundred cycles, and then burn gpu cycles for the next 3800 cycles making no improvements.

I think they’ve inadvertently included Blender’s instantiation phase in the overall rendering time, while not including the transformer instantiation.

I’d be interested to see the time to render the second frame for each system. My hunch is that Blender would be a lot more performant.

I do think the papers results are fascinating in general, but there’s some nuance in the way they’ve configured and timed Blender.

[jsheard]

Also of note is that the RenderFormer tests and Blender tests were done on the same Nvidia A100, which sounds sensible at first glance, but doesn't really make sense because Nvidia's big-iron compute cards (like the A100) lack the raytracing acceleration units present on the rest of their range. The A100 is just the wrong tool for the job here, you'd get vastly better Blender-performance-per-dollar from an Nvidia RTX card.

Blenders benchmark database doesn't have any results for the A100, but even the newer H100 gets smoked by (relatively) cheap consumer hardware.

  Nvidia H100 NVL        -  5,597.13
  GeForce RTX 3090 Ti    -  5,604.69
  Apple M3 Ultra (80C)   -  7,319.21
  GeForce RTX 4090       - 11,082.51
  GeForce RTX 5090       - 15,022.02
  RTX PRO 6000 Blackwell - 16,336.54

[rcxdude]

Yeah, you would generally set blender to have some low minimum number of cycles, maybe have some adaptive noise target, and use a denoising model, especially for preview or draft renders.

[ttoinou]

But rendering engines have been optimized for years and this is a research paper. Probably this technique will also be optimized for years and provide a 10x speedup again

[qayxc]

Sure, but algorithmic complexity beats linear factors, so unless they somehow manage to get from O(N²) to O(log N) for triangle count, this technique cannot ever even come close to established traditional approaches; no matter the linear improvement.