> Just because it was designed to be high-performance doesn't mean it automatically wins on platform support and implementation quality.

I never asserted that. I didn't even qualify what I meant by "BEST". But, let's evaluate the qualities you mention:

> platform support

Vulkan objectively wins here, supporting Windows 7/8/10, Linux, macOS/iOS with a wrapper, Android, etc. Intel has unofficial drivers for their x86 iGPU. Qualcomm recently announced hardware support, along with ARM.

> implementation quality

Vulkan is developed as an open specification, and has a full conformance test for implementations (https://www.khronos.org/vulkan/adopters/). Many aspects of Vulkan are available on GitHub and you can submit PRs. In my experience, drivers on Linux are very good and there are frequent updates. We currently deploy Vulkan at scale in production and haven't had a single issue with reliability.

In addition, the Vulkan validation layers assist with development because they check almost all API invariants and log incorrect usage. This helps to develop programs that work correctly according to the specs.

So, from the driver stack to the client software, Vulkan, IMHO, has a quality and well thought out implementation.

In comparison to DX12, which is developed behind closed doors, we don't know the implementation quality.

I personally haven't heard about any major bugs in Vulkan drivers, but I have seen quite few DX12 demos plagued by bugs. That's my subjective opinion though.

> Direct3D 12 is at the same level as Vulkan

Vulkan is better than DX12 in terms of openness, conformance testing, development tools, platform support, etc. Performance is about the same.

Even Valve agrees: http://www.kitguru.net/components/graphic-cards/anton-shilov...

> OpenGL drivers are inconsistent and buggy.

Agreed :)

I make no argument against what you've said except you used Valve as an "appeal to authority", when they have a vested interest in promoting Vulkan (since SteamOS is based on Linux). So of course they will be persuading developers to use Vulkan over DX12, because it broadens the domain of users who can buy an individual title on Steam.

If you look up the endorsement by Valve, it's not just a straight up "Use Vulkan" but a well reasoned set of arguments and case studies by people with a lot of experience. So, this is not an "appeal to authority", but a reference to an existing body of research which supports my assertions.

By "platform support," I was not referring to the number of platforms supported by the API, but the quality of support for the API provided by the platform(s). Vulkan objectively loses to D3D and Metal here.

We absolutely know the implementation quality of D3D- you don't have to see the source to see its performance, its stability, or its adherence to the spec. On the whole, it's far more consistent and stable than OpenGL and there is no reason to believe Vulkan will change any of that as it uses the same process for specification, development, and deployment.

The Vulkan development process is very different from OpenGL. It's a significant improvement so it's not fair to make this judgement. There is significant evidence: The quality of the API, the number of platforms supported within the first 12 months of publication, the availability of source code and documentation on GitHub (including allowing contributions). These are all things which are far better than the equivalent DX model, and also, in comparison, OpenGL.

None of that directly impacts Vulkan driver implementation quality (which is not open source at all).