Supported shader barycentric coords on OpenGL, Vulkan and Metal

[jay3d]

Fragment shader barycentric coords support following this spec: https://registry.khronos.org/vulkan/specs/1.3-extensions/man/html/VK_KHR_fragment_shader_barycentric.html

I have modified some 3rdparty sources for this to work and I have made PRs of those to their respected repositories:
KhronosGroup/glslang#3198
KhronosGroup/SPIRV-Cross#2137
So when the above gets approved and merged, it will be already here.

[bkaradzic]

👍 Looks good! I'm just going to wait for glslang and SPIRV-Cross to accept it.

[bkaradzic]

You shouldn't be using merge into this branch, rather rebase, so that your changes always appear as the top.

[jay3d]

You shouldn't be using merge into this branch, rather rebase, so that your changes always appear as the top.

I can? It's good to know for next time, thanks! :)

[bkaradzic]

You can even fix this branch by removing undesired merges so that only new changes appear, and then force pushing it.

[bkaradzic]

Any luck with this being accepted in glslang?

[jay3d]

Any luck with this being accepted in glslang?

The spirv-cross part was fixed, but glslang won't work properly and it will remain a hack because of glslang architecture itself.
A better pathway in my guess would be to adopt DXC (slang is still very meh in my tests even worse than spirv-cross/glslang) since the support now is mature, and an alternative path can be added for Metal which can use https://developer.apple.com/metal/shader-converter/ I had success using it with bgfx in my internal branch along with DXC. But I need more time completing DXC integration in bgfx.