I really think the future here is in MoltenVK becoming the default cross platform GPU API
For everyone mad about Metal, remember:
A. Metal came 2 years before Vulkan.
B. Microsoft does their own proprietary API with DirectX.
C. Metal is a high-level language, Vulkan is low-level. Apple wants you to use a high-level language so they have more flexibility in optimizing the low-level for you now and in the future, which Vulkan closes off more.
D. Metal runs on iOS, iPadOS, and tvOS as well, not just macOS. It's a graphics API for all Apple platforms.
E. Because of D, talent for Metal is much more likely to be found with mobile game developers than AAA studios.
F. Game engines actually support Metal - Unity, Unreal, LWJGL, the most common engines run on Metal fine. Don't use Metal as a scapegoat.
Ok so where is the reason Apple can't add Vulkan support to Mac OS?
I don't understand why they would.
They don't control the API - not what is in it, the direction it is going, nor when it is updated. That means they can't integrate it tightly with their OSs. Not from a tech standpoint and not from a release standpoint.
Supporting it in MacOS would mean just having a team working for Khronos, implementing Vulkan on top of MacOS's actual graphics API, Metal, and releasing when they could.
It would seem much better if some other group -- one with an actual stake or interest in it -- would take this on. Not sure who that would be because there doesn't seem to be a good enough reason for any group to do it.
Most game engines probably want to go directly on top of Metal -- they already provide an abstraction layer and probably don't want to have an intermediate one.
GPU makers, even at the best of times, have never been interested, and, of course, they can look forward to zero Mac business in the near future, so that isn't going to change.
Not sure who else there possibly is.
Proper support for Vulkan would not be an abstraction layer. Metal is not the language of the hardware, GPUs operate on assembly like instructions. These are not publicly documented or AFAIK exposed on Mac OS so only Apple would be capable of creating a proper Vulkan driver.
> They don't control the API - not what is in it, the direction it is going, nor when it is updated. That means they can't integrate it tightly with their OSs. Not from a tech standpoint and not from a release standpoint.
What if I told you I can transfer a file between my Mac and PC using software built into Mac OS from a standard controlled by Microsoft.
> Supporting it in MacOS would mean just having a team working for Khronos, implementing Vulkan on top of MacOS's actual graphics API, Metal, and releasing when they could.
This is like saying because Mac and Safari support HTML 5 its like the dev team is working for W3C. Khronos group is a standards organization not generally the implementer.
> Not sure who that would be because there doesn't seem to be a good enough reason for any group to do it.
https://github.com/KhronosGroup/MoltenVK
Plenty of "native" Mac games can't be bothered to utilize Metal directly and just use this instead. This generally results in less than optimal performance or efficiency.
> GPU makers, even at the best of times, have never been interested, and, of course, they can look forward to zero Mac business in the near future, so that isn't going to change.
GPU makers are plenty interested because it sells GPUs and it is exactly how its done on Windows. Back when Nvidia worked on Mac OS they implemented CUDA and OpenGL on Mac.