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by raphlinus·4y ago·view on hn ↗

I don't really agree. I think it's completely valid to explore a GPU architecture in which rasterization is done in software, with a perhaps a bit of support in the ISA. That's what they've done here, and they do demonstrate running OpenGL ES.

The value of this approach depends on the workload. If it's mostly rasterizing large triangles with simple shaders, then a hardware rasterizer buys you a lot. However, as triangles get smaller, a pure software rasterizer can win (as demonstrated by Nanite). And as you spend more time in shaders, the relative amount of overhead from software rasterization decreases; this was shown in the cudaraster paper[1].

Overall, if we can get simpler hardware with more of a focus on compute power, I think that's a good thing, and I think it's completely fine to call that a GPU.

[1]: https://research.nvidia.com/publication/high-performance-sof...

This is essentially where Sony was trying to go with their Cell architecture in the PS3. Only at the very end did they realize that they actually needed a GPU that can do rasterization in hardware. In fact, a lot of games actually did graphics workloads on the SPEs to help out the pretty weak GPU. The concept can definitely work, especially if the driver takes care of all the programmable bits and exposes a more classical graphics pipeline to the host.