d3d12: Report other capabilities

[jp7677]

For Turing+ only.

I'm tempted to report those two also for Turing+.
Since there are no NvAPI_D3D12 equivalents to NvAPI_D3D11_RSSetExclusiveScissorRects or NvAPI_D3D11_RSSetViewportsPixelShadingRates I guess those capabilities refer to D3D12 core functionalities, but should do some research into it first.
Reporting those probably makes no difference in practice.

[Saancreed]

bVariablePixelRateShadingSupported is simple enough I think, afaict this refers to feature that's accessible using ID3D12GraphicsCommandList5::RSSetShadingRate. Though I'd recommend checking if VK_KHR_fragment_shading_rate extension has been enabled on underlying VkDevice.

bExclusiveScissorRectsSupported looks a bit tougher though. It sounds like something that is exposed by VK_NV_scissor_exclusive extension in Vulkan but vkd3d-proton doesn't use it and I don't see a way to access a feature like this neither in D3D12 core API nor in NVAPI D3D12 extensions. Maybe it would be safer to keep reporting false here.

[jp7677]

bVariablePixelRateShadingSupported is simple enough I think, afaict this refers to feature that's accessible using ID3D12GraphicsCommandList5::RSSetShadingRate. Though I'd recommend checking if VK_KHR_fragment_shading_rate extension has been enabled on underlying VkDevice.

Good suggestion. Did that, which should result in the same.

bExclusiveScissorRectsSupported looks a bit tougher though. It sounds like something that is exposed by VK_NV_scissor_exclusive extension in Vulkan but vkd3d-proton doesn't use it and I don't see a way to access a feature like this neither in D3D12 core API nor in NVAPI D3D12 extensions. Maybe it would be safer to keep reporting false here.

I couldn't find anything related to d3d12 either, this hints in your direction https://developer.nvidia.com/vulkan-turing though. Returning false seems sensible.

[Saancreed]

One warning but it's not necessarily something we need to act on.

[Saancreed]

In the incredibly unlikely scenario that we are running this code alongside some ancient version of vkd3d-proton (or usage of the ext is disabled via VKD3D_DISABLE_EXTENSIONS), the safer choice would be to check which extensions were actually enabled on the logical device instead. That would look something like

Com<ID3D12DXVKInteropDevice> device;
if (SUCCEEDED(pDevice->QueryInterface(IID_PPV_ARGS(&device)))) {
    std::vector<const char*> extensions;
    UINT count;
    if (SUCCEEDED(device->GetDeviceExtensions(&count, nullptr))) {
        extensions.resize(count);
        if (SUCCEEDED(device->GetDeviceExtensions(&count, extensions.data())))
            pGraphicsCaps->bVariablePixelRateShadingSupported = std::any_of(extensions.begin(), extensions.end(), [](auto ext) { return ext == std::string_view{VK_KHR_FRAGMENT_SHADING_RATE_EXTENSION_NAME}; });
    }
}

but it's fairly disgusting and probably overcomplicated for such a rare corner-case, so if you are fine with this small risk then let's just leave a comment that would explain potential mismatch and ignore the problem for now.