OpenGL Overload: Implementing OpenGL Over Vulkan

[Azrael5]

vulkan would limit legacy hardware?

[triangle]

Why does it need more than one backend? There already is a Metal -> Vulkan compatibility layer (MoltenVK), but if the idea is to remove this for performance I guess it is understandable. But DX12?! Most drivers that support DX12 are also supporting Vulkan... Would the DX12 backend be used over the Vulkan backend on a Windows 10 that also supports Vulkan? It just sounds kind of stupid from my point of view.

[Zan Lynx]

Why does it need more than one backend? There already is a Metal -> Vulkan compatibility layer (MoltenVK), but if the idea is to remove this for performance I guess it is understandable. But DX12?! Most drivers that support DX12 are also supporting Vulkan... Would the DX12 backend be used over the Vulkan backend on a Windows 10 that also supports Vulkan? It just sounds kind of stupid from my point of view.

That would actually provide the interesting situation of DirectX 12 support on Windows XP and 7.

[computerquip]

Why does it need more than one backend? There already is a Metal -> Vulkan compatibility layer (MoltenVK), but if the idea is to remove this for performance I guess it is understandable. But DX12?! Most drivers that support DX12 are also supporting Vulkan... Would the DX12 backend be used over the Vulkan backend on a Windows 10 that also supports Vulkan? It just sounds kind of stupid from my point of view.

Metal because no Vulkan on macOS and DX12 for porting purposes (supposedly for consoles?) or for benchmark purposes.

[andrebrait]

That would actually provide the interesting situation of DirectX 12 support on Windows XP and 7.

He meant backend, not frontend. DX12 on Windows XP and 7 would require a DX12 frontend with the Vulkan backend.

The app talks to the frontend and the library talks to the backend. So, an OpenGL app would be able to run on any platform with a Vulkan driver. A DX12 backend would provide a way for an OpenGL app to run on a platform with a DX12 driver, but like he said, that would be sorta redundant since a Vulkan backend would already exist.

The DX12 backend is really a curious thing because, as he pointed, drivers that support DX12 also support Vulkan. I think focusing on the Vulkan backend (except for Metal and even then, only focusing on Metal after finishing the Vulkan backend) would be the proper thing to do.