Unreal Engine 5 Ray Tracing Tier 1.0 Support

Created On22/12/2023

Updated On22/12/2023

byDarknessFX

Changes for enable Emulated Ray Tracing with Nvidia GTX (Pascal) GPUs in Unreal Engine (tested with UE5.3.2).

File \Engine\Source\Runtime\D3D12RHI\Private\D3D12Adapter.cpp

					&& FDataDrivenShaderPlatformInfo::GetSupportsRayTracing(GMaxRHIShaderPlatform)
					&& !FParse::Param(FCommandLine::Get(), TEXT("noraytracing")))
				{
					UE_LOG(LogD3D12RHI, Log, TEXT("D3D12 ray tracing tier 1.0 is supported."));

					GRHISupportsRayTracing = RHISupportsRayTracing(GMaxRHIShaderPlatform);
					GRHISupportsRayTracingShaders = GRHISupportsRayTracing && RHISupportsRayTracingShaders(GMaxRHIShaderPlatform);

					if (D3D12Caps5.RaytracingTier >= D3D12_RAYTRACING_TIER_1_1
						&& RootDevice7)
					{

// @Line 1148, comment and replace log entry:
						//UE_LOG(LogD3D12RHI, Log, TEXT("Ray tracing is disabled because D3D12 ray tracing tier 1.1 is required but only tier 1.0 is supported."));
            UE_LOG(LogD3D12RHI, Log, TEXT("Ray tracing tier 1.1 features are disabled (GTX Pascal)."));

File \Engine\Source\Runtime\D3D12RHI\Private\Windows\WindowsD3D12Device.cpp