> Wine already can do DX9 pretty good. I would assume that performance would be low-hanging fruit. OpenGL and DirectX work quite differently, so translating th

> Wine already can do DX9 pretty good. I would assume that performance would be low-hanging fruit. OpenGL and DirectX work quite differently, so translating the calls of one to the other should involve quite a bit of work/CPU cycles. Vulkan, being closer to metal, should be a more straightforward translation target. Example: HLSL-to-GLSL is likely a difficult problem, where HLSL-to-SPIR-V is probably much simpler. > Who cares about DX9 nowadays? Lots of games still support it. In addition this layer could be used for future work in DX11/DX12, instead of the (per my above argument) more complex OpenGL translator.