Why to disable compile vulkan on windows

[zhouhang95]

I only want to use dx12 on win, how to disable compile vulkan.

[cwfitzgerald]

We currently do not allow you to remove backends at runtime, only add rarely-supported ones. We might in some potential future version, but not now.

[zhouhang95]

Not at runtime, at compile.

[zhouhang95]

ash make bin size big, on windows only using DX12 is ok.

[grovesNL]

@zhouhang95 I think @cwfitzgerald meant to say "compile-time" instead of "runtime" in that comment. There is no way to remove backends at compile-time right now.