gl_rasterizer: Use NV_vertex_buffer_unified_memory for vertex buffer robustness
Switch games are allowed to bind less data than what they use in a vertex buffer, the expected behavior here is that these values are read as zero. At the moment of writing this only D3D12, OpenGL and NVN through NV_vertex_buffer_unified_memory support vertex buffer with a size limit. In theory this could be emulated on Vulkan creating a new VkBuffer for each (handle, offset, length) tuple and binding the expected data to it. This is likely going to be slow and memory expensive when used on the vertex buffer and we have to do it on all draws because we can't know without analyzing indices when a game is going to read vertex data out of bounds. This is not a problem on OpenGL's BufferAddressRangeNV because it takes a length parameter, unlike Vulkan's CmdBindVertexBuffers that only takes buffers and offsets (the length is implicit in VkBuffer). It isn't a problem on D3D12 either, because D3D12_VERTEX_BUFFER_VIEW on IASetVertexBuffers takes SizeInBytes as a parameter (although I am not familiar with robustness on D3D12). Currently this only implements buffer ranges for vertex buffers, although indices can also be affected. A KHR_robustness profile is not created, but Nvidia's driver reads out of bound vertex data as zero anyway, this might have to be changed in the future. - Fixes SMO random triangles when capturing an enemy, getting hit, or looking at the environment on certain maps.
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