For a depth buffer in D3D12 that is also going to be used in a texture sampler, the creation (on an Intel HD 5500 igpu) fails. e.g. SDL_GPUTextureCreateInfo type = TEXTURE_2D, format = D32_FLOAT, usage = DEPTH_STENCIL_TARGET | SAMPLER
The error messages are:
D32_FLOAT
D3D12 ERROR: ID3D12Device::CreateShaderResourceView: The Format (0x29, R32_FLOAT) is invalid when creating a View; the
Resource was already created with a fully qualified Format, which is not castable (0x28, D32_FLOAT).
D24_UNORM
D3D12 ERROR: ID3D12Device::CreateShaderResourceView: For the resource format D24_UNORM_S8_UINT, when making a D3D view, the format name for the view can't be R24_UNORM_X8_TYPELESS.
I found this is because the texture format needs to be created as _TYPELESS, then the views (depth stencil view, shader resource view) should then be created as their respective types - e.g. texture = R32_TYPELESS, dsv = D32_FLOAT, srv = R32_FLOAT
Tested and working on:
NVidia RTX 3050 (D3D12 feature set 12_2)
Intel HD 5500 (D3D12 feature set 11_1)
We may want to extend this with additional properties in the future.
Also removed SDL_PROP_GPU_DEVICE_DEBUG_VULKAN_CONFORMANCE_STRING. If we need feature level queries we can add them in the future.
this was causing problems when i was specifying non-zero buffer slots in
`SDL_BindGPUVertexBuffers`, `SDL_GPUVertexAttribute` and
`SDL_GPUVertexBufferDescription`.
`firstSlot + 1` is simply copied over from metal and d3d12 backends.
The GPU API doesn't currently support transparent windows (transparent swapchain effects doesn't seem possible on D3D12) so we should explicitly fail so users don't expect transparency and then not get it.
Fixes https://github.com/libsdl-org/SDL/issues/12410
If the window is flagged with SDL_WINDOW_TRANSPARENT, create the associated swapchain with a composite alpha value that supports blending, if available.
Fixes transparent windows on the Vulkan backend, and prevents possible validation errors by ensuring that the composite alpha value is always a valid bit in VkSurfaceCapabilitiesKHR::supportedCompositeAlpha.