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Wowfunhappy ◴[] No.41803351[source]
> Tessellation enables games like The Witcher 3 to generate geometry. The M1 has hardware tessellation, but it is too limited for DirectX, Vulkan, or OpenGL. We must instead tessellate with arcane compute shaders

> Geometry shaders are an older, cruder method to generate geometry. Like tessellation, the M1 lacks geometry shader hardware so we emulate with compute.

Is this potentially a part of why Apple doesn't want to support Vulkan themselves? Because they don't want to implement common Vulkan features in hardware, which leads to less than ideal performance?

(I realize performance is still relatively fast in practice, which is awesome!)

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VHRanger ◴[] No.41803686[source]
> Is this potentially a part of why Apple doesn't want to support Vulkan? Because they don't want to implement common Vulkan features in hardware, which leads to less than ideal performance?

Yes, it's a big reason.

I tried to port the yuzu switch emulator to macos a few years ago, and you end up having to write compute shaders that emulate the geometry shaders to make that work.

Even fairly modern games like Mario Odyssey use geometry shaders.

Needless to say, I was not enough of a wizard to make this happen!

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ronsor ◴[] No.41805360[source]
Why couldn't you just use MoltenVK?
replies(1): >>41805897 #
1. slimsag ◴[] No.41805897[source]
MoltenVK doesn't support geometry shaders for ~3 years now[0]

[0] https://github.com/KhronosGroup/MoltenVK/issues/1524