DirectX Raytracing samples

Author: walbourn

Kits/D3D12RaytracingFallback/Include/D3D12RaytracingFallback.h

@@ -0,0 +1,172 @@
+///////////////////////////////////////////////////////////////////////////////
+//                                                                           //
+// D3D12RaytracingFallback.h                                                 //
+//                                                                           //
+// Provides a simplified interface for the DX12 Ray Tracing interface that   //
+// will use native DX12 ray tracing when available. For drivers that do not  //
+// support ray tracing, a fallback compute-shader based solution will be     //
+// used instead.                                                             //    
+//                                                                           //
+///////////////////////////////////////////////////////////////////////////////
+
+#pragma once
+#include "d3d12_1.h"
+
+struct EMULATED_GPU_POINTER
+{
+    UINT32 OffsetInBytes;
+    UINT32 DescriptorHeapIndex;
+};
+
+struct WRAPPED_GPU_POINTER
+{
+    union
+    {
+        EMULATED_GPU_POINTER EmulatedGpuPtr;
+        D3D12_GPU_VIRTUAL_ADDRESS GpuVA;
+    };
+
+    WRAPPED_GPU_POINTER operator+(UINT64 offset)
+    {
+        WRAPPED_GPU_POINTER pointer = *this;
+        pointer.GpuVA += offset;
+        return pointer;
+    }
+};
+
+typedef struct D3D12_RAYTRACING_FALLBACK_INSTANCE_DESC
+{
+    FLOAT Transform[3][4];
+    UINT InstanceID : 24;
+    UINT InstanceMask : 8;
+    UINT InstanceContributionToHitGroupIndex : 24;
+    UINT Flags : 8;
+    WRAPPED_GPU_POINTER AccelerationStructure;
+}     D3D12_RAYTRACING_FALLBACK_INSTANCE_DESC;
+
+class
+_declspec(uuid("539e5c40-df25-4c7d-81d8-6537f54306ed"))
+ID3D12RaytracingFallbackStateObject : public IUnknown
+{
+public:
+    virtual ~ID3D12RaytracingFallbackStateObject() {};
+
+    virtual void *STDMETHODCALLTYPE GetShaderIdentifier(
+        _In_  LPCWSTR pExportName) = 0;
+
+    virtual UINT64 STDMETHODCALLTYPE GetShaderStackSize(
+        _In_  LPCWSTR pExportName) = 0;
+
+    virtual UINT64 STDMETHODCALLTYPE GetPipelineStackSize(void) = 0;
+
+    virtual void STDMETHODCALLTYPE SetPipelineStackSize(
+        UINT64 PipelineStackSizeInBytes) = 0;
+
+    virtual ID3D12StateObject *GetStateObject() = 0;
+};
+
+class
+_declspec(uuid("348a2a6b-6760-4b78-a9a7-1758b6f78d46"))
+ID3D12RaytracingFallbackCommandList : public IUnknown
+{
+public:
+    virtual ~ID3D12RaytracingFallbackCommandList() {}
+
+    virtual void BuildRaytracingAccelerationStructure(
+        _In_  const D3D12_BUILD_RAYTRACING_ACCELERATION_STRUCTURE_DESC *pDesc,
+        _In_  UINT NumPostbuildInfoDescs,
+        _In_reads_opt_(NumPostbuildInfoDescs)  const D3D12_RAYTRACING_ACCELERATION_STRUCTURE_POSTBUILD_INFO_DESC *pPostbuildInfoDescs) = 0;
+
+    virtual void STDMETHODCALLTYPE EmitRaytracingAccelerationStructurePostbuildInfo(
+        _In_  const D3D12_RAYTRACING_ACCELERATION_STRUCTURE_POSTBUILD_INFO_DESC *pDesc,
+        _In_  UINT NumSourceAccelerationStructures,
+        _In_reads_(NumSourceAccelerationStructures)  const D3D12_GPU_VIRTUAL_ADDRESS *pSourceAccelerationStructureData) = 0;
+
+    virtual void STDMETHODCALLTYPE CopyRaytracingAccelerationStructure(
+        _In_  D3D12_GPU_VIRTUAL_ADDRESS DestAccelerationStructureData,
+        _In_  D3D12_GPU_VIRTUAL_ADDRESS SourceAccelerationStructureData,
+        _In_  D3D12_RAYTRACING_ACCELERATION_STRUCTURE_COPY_MODE Mode) = 0;
+
+    virtual void STDMETHODCALLTYPE SetDescriptorHeaps(
+        _In_  UINT NumDescriptorHeaps,
+        _In_reads_(NumDescriptorHeaps)  ID3D12DescriptorHeap *const *ppDescriptorHeaps) = 0;
+
+    virtual void STDMETHODCALLTYPE SetTopLevelAccelerationStructure(
+        _In_  UINT RootParameterIndex,
+        _In_  WRAPPED_GPU_POINTER  BufferLocation) = 0;
+
+    virtual void STDMETHODCALLTYPE SetPipelineState1(
+        _In_  ID3D12RaytracingFallbackStateObject *pStateObject) = 0;
+
+    virtual void STDMETHODCALLTYPE DispatchRays(
+        _In_  const D3D12_DISPATCH_RAYS_DESC *pDesc) = 0;
+};
+
+class
+_declspec(uuid("0a662ea0-ab43-423a-848f-4824ae4b25ba"))
+ID3D12RaytracingFallbackDevice : public IUnknown
+{
+public:
+    virtual ~ID3D12RaytracingFallbackDevice() {};
+
+    virtual bool UsingRaytracingDriver() = 0;
+
+    // Automatically determine how to create WRAPPED_GPU_POINTER based on UsingRaytracingDriver()
+    virtual WRAPPED_GPU_POINTER GetWrappedPointerSimple(UINT32 DescriptorHeapIndex, D3D12_GPU_VIRTUAL_ADDRESS GpuVA) = 0;
+
+    // Pre-condition: UsingRaytracingDriver() must be false
+    virtual WRAPPED_GPU_POINTER GetWrappedPointerFromDescriptorHeapIndex(UINT32 DescriptorHeapIndex, UINT32 OffsetInBytes = 0) = 0;
+
+    // Pre-condition: UsingRaytracingDriver() must be true
+    virtual WRAPPED_GPU_POINTER GetWrappedPointerFromGpuVA(D3D12_GPU_VIRTUAL_ADDRESS gpuVA) = 0;
+
+    virtual D3D12_RESOURCE_STATES GetAccelerationStructureResourceState() = 0;
+    
+    virtual UINT STDMETHODCALLTYPE GetShaderIdentifierSize(void) = 0;
+
+    virtual HRESULT STDMETHODCALLTYPE CreateStateObject(
+        const D3D12_STATE_OBJECT_DESC *pDesc,
+        REFIID riid,
+        _COM_Outptr_  void **ppStateObject) = 0;
+
+    virtual void STDMETHODCALLTYPE GetRaytracingAccelerationStructurePrebuildInfo(
+        _In_  const D3D12_BUILD_RAYTRACING_ACCELERATION_STRUCTURE_INPUTS *pDesc,
+        _Out_  D3D12_RAYTRACING_ACCELERATION_STRUCTURE_PREBUILD_INFO *pInfo) = 0;
+
+    virtual void QueryRaytracingCommandList(
+        ID3D12GraphicsCommandList *pCommandList, 
+        REFIID riid,
+        _COM_Outptr_  void **ppRaytracingCommandList) = 0;
+
+    virtual HRESULT STDMETHODCALLTYPE CreateRootSignature(
+        _In_  UINT nodeMask,
+        _In_reads_(blobLengthInBytes)  const void *pBlobWithRootSignature,
+        _In_  SIZE_T blobLengthInBytes,
+        REFIID riid,
+        _COM_Outptr_  void **ppvRootSignature) = 0;
+
+    virtual HRESULT D3D12SerializeVersionedRootSignature(
+        _In_ const D3D12_VERSIONED_ROOT_SIGNATURE_DESC* pRootSignature,
+        _Out_ ID3DBlob** ppBlob,
+        _Always_(_Outptr_opt_result_maybenull_) ID3DBlob** ppErrorBlob) = 0;
+
+    virtual HRESULT WINAPI D3D12SerializeRootSignature(
+        _In_ const D3D12_ROOT_SIGNATURE_DESC* pRootSignature,
+        _In_ D3D_ROOT_SIGNATURE_VERSION Version,
+        _Out_ ID3DBlob** ppBlob,
+        _Always_(_Outptr_opt_result_maybenull_) ID3DBlob** ppErrorBlob) = 0;
+};
+
+enum CreateRaytracingFallbackDeviceFlags
+{
+    None = 0x0,
+    ForceComputeFallback = 0x1,
+    EnableRootDescriptorsInShaderRecords = 0x2
+};
+
+HRESULT D3D12CreateRaytracingFallbackDevice(
+    _In_ ID3D12Device *pDevice, 
+    _In_ DWORD createRaytracingFallbackDeviceFlags,
+    _In_ UINT NodeMask,
+    _In_ REFIID riid,
+    _COM_Outptr_opt_ void** ppDevice);