Files
UnrealEngine/Engine/Source/Runtime/Renderer/Private/DistanceFieldLightingPost.cpp
2025-05-18 13:04:45 +08:00

624 lines
30 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
/*=============================================================================
DistanceFieldLightingPost.cpp
=============================================================================*/
#include "DistanceFieldLightingPost.h"
#include "PostProcess/PostProcessing.h"
#include "PostProcess/SceneFilterRendering.h"
#include "DistanceFieldLightingShared.h"
#include "DistanceFieldAmbientOcclusion.h"
#include "CompositionLighting/PostProcessAmbientOcclusion.h"
#include "PipelineStateCache.h"
#include "ScenePrivate.h"
#include "SceneProxies/SkyLightSceneProxy.h"
#include "DataDrivenShaderPlatformInfo.h"
int32 GAOUseHistory = 1;
FAutoConsoleVariableRef CVarAOUseHistory(
TEXT("r.AOUseHistory"),
GAOUseHistory,
TEXT("Whether to apply a temporal filter to the distance field AO, which reduces flickering but also adds trails when occluders are moving."),
ECVF_RenderThreadSafe
);
int32 GAOClearHistory = 0;
FAutoConsoleVariableRef CVarAOClearHistory(
TEXT("r.AOClearHistory"),
GAOClearHistory,
TEXT(""),
ECVF_RenderThreadSafe
);
int32 GAOHistoryStabilityPass = 1;
FAutoConsoleVariableRef CVarAOHistoryStabilityPass(
TEXT("r.AOHistoryStabilityPass"),
GAOHistoryStabilityPass,
TEXT("Whether to gather stable results to fill in holes in the temporal reprojection. Adds some GPU cost but improves temporal stability with foliage."),
ECVF_RenderThreadSafe
);
float GAOHistoryWeight = .85f;
FAutoConsoleVariableRef CVarAOHistoryWeight(
TEXT("r.AOHistoryWeight"),
GAOHistoryWeight,
TEXT("Amount of last frame's AO to lerp into the final result. Higher values increase stability, lower values have less streaking under occluder movement."),
ECVF_RenderThreadSafe
);
float GAOHistoryDistanceThreshold = 30;
FAutoConsoleVariableRef CVarAOHistoryDistanceThreshold(
TEXT("r.AOHistoryDistanceThreshold"),
GAOHistoryDistanceThreshold,
TEXT("World space distance threshold needed to discard last frame's DFAO results. Lower values reduce ghosting from characters when near a wall but increase flickering artifacts."),
ECVF_RenderThreadSafe
);
float GAOViewFadeDistanceScale = .7f;
FAutoConsoleVariableRef CVarAOViewFadeDistanceScale(
TEXT("r.AOViewFadeDistanceScale"),
GAOViewFadeDistanceScale,
TEXT("Distance over which AO will fade out as it approaches r.AOMaxViewDistance, as a fraction of r.AOMaxViewDistance."),
ECVF_RenderThreadSafe
);
bool UseAOHistoryStabilityPass()
{
extern int32 GDistanceFieldAOQuality;
return GAOHistoryStabilityPass && GDistanceFieldAOQuality >= 2;
}
bool ShouldCompileDFLightingPostShaders(EShaderPlatform ShaderPlatform)
{
return ShouldCompileDistanceFieldShaders(ShaderPlatform);
}
BEGIN_SHADER_PARAMETER_STRUCT(FGeometryAwareUpsampleParameters, )
SHADER_PARAMETER_RDG_TEXTURE(Texture2D, DistanceFieldNormalTexture)
SHADER_PARAMETER_SAMPLER(SamplerState, DistanceFieldNormalSampler)
SHADER_PARAMETER_RDG_TEXTURE(Texture2D, BentNormalAOTexture)
SHADER_PARAMETER_SAMPLER(SamplerState, BentNormalAOSampler)
SHADER_PARAMETER(FScreenTransform, UVToScreenPos)
SHADER_PARAMETER(FVector4f, BentNormalBufferAndTexelSize)
SHADER_PARAMETER(FVector2f, DistanceFieldGBufferTexelSize)
SHADER_PARAMETER(FVector2f, DistanceFieldGBufferJitterOffset)
SHADER_PARAMETER(FVector2f, JitterOffset)
SHADER_PARAMETER(float, DistanceFadeScale)
END_SHADER_PARAMETER_STRUCT()
FGeometryAwareUpsampleParameters SetupGeometryAwareUpsampleParameters(const FViewInfo& View, FRDGTextureRef DistanceFieldNormal, FRDGTextureRef DistanceFieldAOBentNormal)
{
extern FVector2f GetJitterOffset(const FViewInfo& View);
FVector2f const JitterOffsetValue = GetJitterOffset(View);
const FIntPoint DownsampledBufferSize = GetBufferSizeForAO(View);
const FVector2f BaseLevelTexelSizeValue(1.0f / DownsampledBufferSize.X, 1.0f / DownsampledBufferSize.Y);
extern FIntPoint GetBufferSizeForConeTracing(const FViewInfo& View);
const FIntPoint ConeTracingBufferSize = GetBufferSizeForConeTracing(View);
const FVector4f BentNormalBufferAndTexelSizeValue(ConeTracingBufferSize.X, ConeTracingBufferSize.Y, 1.0f / ConeTracingBufferSize.X, 1.0f / ConeTracingBufferSize.Y);
extern float GAOViewFadeDistanceScale;
const float DistanceFadeScaleValue = 1.0f / ((1.0f - GAOViewFadeDistanceScale) * GetMaxAOViewDistance());
const FIntRect AOViewRect = FIntRect(FIntPoint::ZeroValue, FIntPoint::DivideAndRoundDown(View.ViewRect.Size(), GAODownsampleFactor));
FGeometryAwareUpsampleParameters ShaderParameters;
ShaderParameters.DistanceFieldNormalTexture = DistanceFieldNormal;
ShaderParameters.DistanceFieldNormalSampler = TStaticSamplerState<SF_Point, AM_Clamp, AM_Clamp, AM_Clamp>::GetRHI();
ShaderParameters.BentNormalAOTexture = DistanceFieldAOBentNormal;
ShaderParameters.BentNormalAOSampler = TStaticSamplerState<SF_Bilinear, AM_Clamp, AM_Clamp, AM_Clamp>::GetRHI();
ShaderParameters.UVToScreenPos = FScreenTransform::ChangeTextureBasisFromTo(FScreenPassTextureViewport(DownsampledBufferSize, AOViewRect), FScreenTransform::ETextureBasis::TextureUV, FScreenTransform::ETextureBasis::ScreenPosition);
ShaderParameters.BentNormalBufferAndTexelSize = BentNormalBufferAndTexelSizeValue;
ShaderParameters.DistanceFieldGBufferTexelSize = BaseLevelTexelSizeValue;
ShaderParameters.DistanceFieldGBufferJitterOffset = BaseLevelTexelSizeValue * JitterOffsetValue;
ShaderParameters.JitterOffset = JitterOffsetValue;
ShaderParameters.DistanceFadeScale = DistanceFadeScaleValue;
return ShaderParameters;
}
class FUpdateHistoryDepthRejectionPS : public FGlobalShader
{
public:
DECLARE_GLOBAL_SHADER(FUpdateHistoryDepthRejectionPS);
SHADER_USE_PARAMETER_STRUCT(FUpdateHistoryDepthRejectionPS, FGlobalShader);
BEGIN_SHADER_PARAMETER_STRUCT(FParameters, )
SHADER_PARAMETER_STRUCT_REF(FViewUniformShaderParameters, View)
SHADER_PARAMETER_STRUCT_INCLUDE(FSceneTextureShaderParameters, SceneTextures)
SHADER_PARAMETER_STRUCT_INCLUDE(FAOParameters, AOParameters)
SHADER_PARAMETER_STRUCT_INCLUDE(FGeometryAwareUpsampleParameters, GeometryAwareUpsampleParameters)
SHADER_PARAMETER_RDG_TEXTURE(Texture2D, BentNormalHistoryTexture)
SHADER_PARAMETER_SAMPLER(SamplerState, BentNormalHistorySampler)
SHADER_PARAMETER_RDG_TEXTURE(Texture2D, VelocityTexture)
SHADER_PARAMETER_SAMPLER(SamplerState, VelocityTextureSampler)
SHADER_PARAMETER(FVector4f, HistoryScreenPositionScaleBias)
SHADER_PARAMETER(FVector4f, HistoryUVMinMax)
SHADER_PARAMETER(float, HistoryWeight)
SHADER_PARAMETER(float, HistoryDistanceThreshold)
SHADER_PARAMETER(float, UseHistoryFilter)
RENDER_TARGET_BINDING_SLOTS()
END_SHADER_PARAMETER_STRUCT()
static bool ShouldCompilePermutation(const FGlobalShaderPermutationParameters& Parameters)
{
return ShouldCompileDFLightingPostShaders(Parameters.Platform);
}
static void ModifyCompilationEnvironment(const FGlobalShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
OutEnvironment.SetDefine(TEXT("DOWNSAMPLE_FACTOR"), GAODownsampleFactor);
}
};
IMPLEMENT_GLOBAL_SHADER(FUpdateHistoryDepthRejectionPS, "/Engine/Private/DistanceFieldLightingPost.usf", "UpdateHistoryDepthRejectionPS", SF_Pixel);
class FFilterHistoryPS : public FGlobalShader
{
public:
DECLARE_GLOBAL_SHADER(FFilterHistoryPS);
SHADER_USE_PARAMETER_STRUCT(FFilterHistoryPS, FGlobalShader);
BEGIN_SHADER_PARAMETER_STRUCT(FParameters, )
SHADER_PARAMETER_STRUCT_REF(FViewUniformShaderParameters, View)
SHADER_PARAMETER_STRUCT_INCLUDE(FSceneTextureShaderParameters, SceneTextures)
SHADER_PARAMETER_RDG_TEXTURE(Texture2D, BentNormalAOTexture)
SHADER_PARAMETER_SAMPLER(SamplerState, BentNormalAOSampler)
SHADER_PARAMETER(FVector2f, BentNormalAOTexelSize)
SHADER_PARAMETER(FVector2f, MaxSampleBufferUV)
SHADER_PARAMETER(float, HistoryWeight)
RENDER_TARGET_BINDING_SLOTS()
END_SHADER_PARAMETER_STRUCT()
class FManuallyClampUV : SHADER_PERMUTATION_BOOL("MANUALLY_CLAMP_UV");
using FPermutationDomain = TShaderPermutationDomain<FManuallyClampUV>;
static bool ShouldCompilePermutation(const FGlobalShaderPermutationParameters& Parameters)
{
return ShouldCompileDFLightingPostShaders(Parameters.Platform);
}
static void ModifyCompilationEnvironment(const FGlobalShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
OutEnvironment.SetDefine(TEXT("DOWNSAMPLE_FACTOR"), GAODownsampleFactor);
}
};
IMPLEMENT_GLOBAL_SHADER(FFilterHistoryPS, "/Engine/Private/DistanceFieldLightingPost.usf", "FilterHistoryPS", SF_Pixel);
class FGeometryAwareUpsamplePS : public FGlobalShader
{
public:
DECLARE_GLOBAL_SHADER(FGeometryAwareUpsamplePS);
SHADER_USE_PARAMETER_STRUCT(FGeometryAwareUpsamplePS, FGlobalShader);
BEGIN_SHADER_PARAMETER_STRUCT(FParameters, )
SHADER_PARAMETER_STRUCT_REF(FViewUniformShaderParameters, View)
SHADER_PARAMETER_STRUCT_INCLUDE(FAOParameters, AOParameters)
SHADER_PARAMETER_STRUCT_INCLUDE(FGeometryAwareUpsampleParameters, GeometryAwareUpsampleParameters)
RENDER_TARGET_BINDING_SLOTS()
END_SHADER_PARAMETER_STRUCT()
static bool ShouldCompilePermutation(const FGlobalShaderPermutationParameters& Parameters)
{
return ShouldCompileDFLightingPostShaders(Parameters.Platform);
}
static void ModifyCompilationEnvironment(const FGlobalShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
OutEnvironment.SetDefine(TEXT("DOWNSAMPLE_FACTOR"), GAODownsampleFactor);
}
};
IMPLEMENT_SHADER_TYPE(,FGeometryAwareUpsamplePS, TEXT("/Engine/Private/DistanceFieldLightingPost.usf"), TEXT("GeometryAwareUpsamplePS"), SF_Pixel);
void AllocateOrReuseAORenderTarget(FRDGBuilder& GraphBuilder, const FViewInfo& View, FRDGTextureRef& Texture, const TCHAR* Name, EPixelFormat Format, ETextureCreateFlags Flags)
{
if (!Texture)
{
const FIntPoint BufferSize = GetBufferSizeForAO(View);
const FRDGTextureDesc Desc = FRDGTextureDesc::Create2D(BufferSize, Format, FClearValueBinding::None, Flags | TexCreate_ShaderResource | TexCreate_RenderTargetable | TexCreate_UAV);
Texture = GraphBuilder.CreateTexture(Desc, Name);
AddClearUAVPass(GraphBuilder, GraphBuilder.CreateUAV(Texture), FLinearColor::Black);
}
}
void GeometryAwareUpsample(FRDGBuilder& GraphBuilder, const FViewInfo& View, FRDGTextureRef DistanceFieldAOBentNormal, FRDGTextureRef DistanceFieldNormal, FRDGTextureRef BentNormalInterpolation, const FDistanceFieldAOParameters& Parameters)
{
auto* PassParameters = GraphBuilder.AllocParameters<FGeometryAwareUpsamplePS::FParameters>();
PassParameters->View = View.ViewUniformBuffer;
PassParameters->AOParameters = DistanceField::SetupAOShaderParameters(Parameters);
PassParameters->GeometryAwareUpsampleParameters = SetupGeometryAwareUpsampleParameters(View, DistanceFieldNormal, BentNormalInterpolation ? BentNormalInterpolation : GSystemTextures.GetWhiteDummy(GraphBuilder));
PassParameters->RenderTargets[0] = FRenderTargetBinding(DistanceFieldAOBentNormal, ERenderTargetLoadAction::ELoad);
auto VertexShader = View.ShaderMap->GetShader<FPostProcessVS>();
auto PixelShader = View.ShaderMap->GetShader<FGeometryAwareUpsamplePS>();
ClearUnusedGraphResources(PixelShader, PassParameters);
GraphBuilder.AddPass(
RDG_EVENT_NAME("GeometryAwareUpsample"),
PassParameters,
ERDGPassFlags::Raster,
[PassParameters, VertexShader, PixelShader, &View](FRDGAsyncTask, FRHICommandList& RHICmdList)
{
const FIntPoint AOBufferSize = GetBufferSizeForAO(View);
const FIntPoint AOViewSize = View.ViewRect.Size() / GAODownsampleFactor;
RHICmdList.SetViewport(0, 0, 0.0f, AOViewSize.X, AOViewSize.Y, 1.0f);
FGraphicsPipelineStateInitializer GraphicsPSOInit;
RHICmdList.ApplyCachedRenderTargets(GraphicsPSOInit);
GraphicsPSOInit.RasterizerState = TStaticRasterizerState<FM_Solid, CM_None>::GetRHI();
GraphicsPSOInit.DepthStencilState = TStaticDepthStencilState<false, CF_Always>::GetRHI();
GraphicsPSOInit.BlendState = TStaticBlendState<>::GetRHI();
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GFilterVertexDeclaration.VertexDeclarationRHI;
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit, 0);
SetShaderParameters(RHICmdList, PixelShader, PixelShader.GetPixelShader(), *PassParameters);
DrawRectangle(
RHICmdList,
0, 0,
AOViewSize.X, AOViewSize.Y,
0, 0,
AOViewSize.X, AOViewSize.Y,
AOViewSize,
AOBufferSize,
VertexShader);
});
}
bool DistanceFieldAOUseHistory(const FViewInfo& View)
{
// Disable AO history for cube map captures to save memory. AO history (DistanceFieldAOHistoryRT) is sized to the scene texture extents, meaning
// the size is proportional to the front buffer resolution, regardless of the resolution of the cube map capture itself. This then gets multiplied
// by 6 for cube map faces. This totals around 25 MB at 1080p or 100 MB at 4K resolution.
//
// JHOERNER_TODO: Ideally, the code would be rewritten so DistanceFieldAOHistoryRT is sized to the view rectangle, rather than scene texture extents.
// The goal of scene texture extents is to reuse render target memory on platforms like PC, by making all scene renders use the same sized render
// targets for things like gbuffers. This advantage doesn't apply to temporal history buffers, since these persist across frames and are unique per
// scene view state, and never shared. As an example, temporal volumetric cloud buffers (VolumetricCloudRenderTarget) are scaled to the view rect,
// and so don't involve a similar memory waste.
//
// I did investigate fixing the memory waste myself, and started attempting it, but it's an involved process due to the number of places in the code
// you'd need to touch. I figured it would be better if someone that has worked with the code before did the changes, to make sure nothing relevant
// was missed, and hopefully they'd be able to visually tell if it was working correctly.
//
// At a basic level, you'd modify UpdateHistory below so instead of using "View.GetSceneTexturesConfig().Extent" to determine the history dimensions,
// you'd use the view rect (multiple places in that function). You'd eliminate "HistoryScreenPositionScaleBiasValue" and "HistoryUVMinMaxValue" scale
// and clamping factors when reading from the history in shaders. The input scene textures (VelocityTexture, etc) would still be in scene texture
// space, so there would be a mix of UV math going on, depending on what textures you were sampling from.
//
// If it was just the shaders in UpdateHistory, I'd give it a shot, but there are additional shaders referencing "BentNormalAOTexture", including from
// DistanceFieldAOShared.ush and DistanceFieldLightingPost.usf. You'd need to update all the shaders, and possibly add extra parameters to make
// information available about the resolution of the history (can't use View.BufferSizeAndInvSize). Any typos could cause artifacts which will only
// be visually obvious if you set up a synthetic test where the scene texture extents don't match the view rect (you should be able to accomplish
// this for debug purposes by modifying FSceneTextureExtentState::Compute to add some padding to the scene textures).
//
return GAOUseHistory && !View.bIsSceneCaptureCube;
}
void UpdateHistory(
FRDGBuilder& GraphBuilder,
const FViewInfo& View,
const TCHAR* BentNormalHistoryRTName,
const FSceneTextures& SceneTextures,
FRDGTextureRef VelocityTexture,
FRDGTextureRef DistanceFieldNormal,
FRDGTextureRef BentNormalInterpolation,
/** Contains last frame's history, if non-NULL. This will be updated with the new frame's history. */
FIntRect* DistanceFieldAOHistoryViewRect,
TRefCountPtr<IPooledRenderTarget>* BentNormalHistoryState,
/** Output of Temporal Reprojection for the next step in the pipeline. */
FRDGTextureRef& BentNormalHistoryOutput,
const FDistanceFieldAOParameters& Parameters)
{
const FRDGSystemTextures& SystemTextures = FRDGSystemTextures::Get(GraphBuilder);
const FIntPoint AOBufferSize = GetBufferSizeForAO(View);
const FIntPoint AOViewSize = View.ViewRect.Size() / GAODownsampleFactor;
if (BentNormalHistoryState && DistanceFieldAOUseHistory(View))
{
if (*BentNormalHistoryState
&& !View.bCameraCut
&& !View.bPrevTransformsReset
&& !GAOClearHistory
// If the scene render targets reallocate, toss the history so we don't read uninitialized data
&& (*BentNormalHistoryState)->GetDesc().Extent == AOBufferSize)
{
FRDGTextureRef BentNormalHistoryTexture = GraphBuilder.RegisterExternalTexture(*BentNormalHistoryState);
ETextureCreateFlags HistoryPassOutputFlags = ETextureCreateFlags(UseAOHistoryStabilityPass() ? GFastVRamConfig.DistanceFieldAOHistory : TexCreate_None);
// Reuse a render target from the pool with a consistent name, for vis purposes
FRDGTextureRef NewBentNormalHistory = nullptr;
AllocateOrReuseAORenderTarget(GraphBuilder, View, NewBentNormalHistory, BentNormalHistoryRTName, PF_FloatRGBA, HistoryPassOutputFlags);
{
FIntRect PrevHistoryViewRect = *DistanceFieldAOHistoryViewRect;
auto* PassParameters = GraphBuilder.AllocParameters<FUpdateHistoryDepthRejectionPS::FParameters>();
PassParameters->View = View.ViewUniformBuffer;
PassParameters->SceneTextures = SceneTextures.GetSceneTextureShaderParameters(View.FeatureLevel);;
PassParameters->AOParameters = DistanceField::SetupAOShaderParameters(Parameters);
PassParameters->GeometryAwareUpsampleParameters = SetupGeometryAwareUpsampleParameters(View, DistanceFieldNormal, BentNormalInterpolation);
PassParameters->BentNormalHistoryTexture = BentNormalHistoryTexture;
PassParameters->BentNormalHistorySampler = TStaticSamplerState<SF_Bilinear, AM_Clamp, AM_Clamp, AM_Clamp>::GetRHI();
PassParameters->VelocityTexture = GetIfProduced(VelocityTexture, SystemTextures.Black);
PassParameters->VelocityTextureSampler = TStaticSamplerState<SF_Bilinear, AM_Clamp, AM_Clamp, AM_Clamp>::GetRHI();
PassParameters->HistoryWeight = GAOHistoryWeight;
PassParameters->HistoryDistanceThreshold = GAOHistoryDistanceThreshold;
PassParameters->UseHistoryFilter = UseAOHistoryStabilityPass() ? 1.0f : 0.0f;
{
const float InvBufferSizeX = 1.0f / AOBufferSize.X;
const float InvBufferSizeY = 1.0f / AOBufferSize.Y;
const FVector4f HistoryScreenPositionScaleBiasValue(
PrevHistoryViewRect.Width() * InvBufferSizeX / +2.0f,
PrevHistoryViewRect.Height() * InvBufferSizeY / (-2.0f * GProjectionSignY),
(PrevHistoryViewRect.Height() / 2.0f + PrevHistoryViewRect.Min.Y) * InvBufferSizeY,
(PrevHistoryViewRect.Width() / 2.0f + PrevHistoryViewRect.Min.X) * InvBufferSizeX);
// Pull in the max UV to exclude the region which will read outside the viewport due to bilinear filtering
const FVector4f HistoryUVMinMaxValue(
(PrevHistoryViewRect.Min.X + 0.5f) * InvBufferSizeX,
(PrevHistoryViewRect.Min.Y + 0.5f) * InvBufferSizeY,
(PrevHistoryViewRect.Max.X - 0.5f) * InvBufferSizeX,
(PrevHistoryViewRect.Max.Y - 0.5f) * InvBufferSizeY);
PassParameters->HistoryScreenPositionScaleBias = HistoryScreenPositionScaleBiasValue;
PassParameters->HistoryUVMinMax = HistoryUVMinMaxValue;
}
PassParameters->RenderTargets[0] = FRenderTargetBinding(NewBentNormalHistory, ERenderTargetLoadAction::ELoad);
TShaderMapRef<FPostProcessVS> VertexShader(View.ShaderMap);
TShaderMapRef<FUpdateHistoryDepthRejectionPS> PixelShader(View.ShaderMap);
ClearUnusedGraphResources(PixelShader, PassParameters);
GraphBuilder.AddPass(
RDG_EVENT_NAME("UpdateHistory"),
PassParameters,
ERDGPassFlags::Raster,
[PassParameters, VertexShader, PixelShader, &View, AOBufferSize, AOViewSize]
(FRDGAsyncTask, FRHICommandList& RHICmdList)
{
RHICmdList.SetViewport(0, 0, 0.0f, AOViewSize.X, AOViewSize.Y, 1.0f);
FGraphicsPipelineStateInitializer GraphicsPSOInit;
RHICmdList.ApplyCachedRenderTargets(GraphicsPSOInit);
GraphicsPSOInit.RasterizerState = TStaticRasterizerState<FM_Solid, CM_None>::GetRHI();
GraphicsPSOInit.DepthStencilState = TStaticDepthStencilState<false, CF_Always>::GetRHI();
GraphicsPSOInit.BlendState = TStaticBlendState<>::GetRHI();
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GFilterVertexDeclaration.VertexDeclarationRHI;
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit, 0);
SetShaderParameters(RHICmdList, PixelShader, PixelShader.GetPixelShader(), *PassParameters);
DrawRectangle(
RHICmdList,
0, 0,
AOViewSize.X, AOViewSize.Y,
0, 0,
AOViewSize.X, AOViewSize.Y,
AOViewSize,
AOBufferSize,
VertexShader);
});
}
if (UseAOHistoryStabilityPass())
{
const FRDGTextureDesc& HistoryDesc = BentNormalHistoryTexture->Desc;
// Reallocate history if buffer sizes have changed
if (HistoryDesc.Extent != AOBufferSize)
{
GRenderTargetPool.FreeUnusedResource(*BentNormalHistoryState);
*BentNormalHistoryState = nullptr;
// Update the view state's render target reference with the new history
AllocateOrReuseAORenderTarget(GraphBuilder, View, BentNormalHistoryTexture, BentNormalHistoryRTName, PF_FloatRGBA);
}
const bool bManuallyClampUV = View.ViewRect.Min != FIntPoint::ZeroValue || View.ViewRect.Max != AOBufferSize;
FFilterHistoryPS::FPermutationDomain PermutationVector;
PermutationVector.Set<FFilterHistoryPS::FManuallyClampUV>(bManuallyClampUV);
auto VertexShader = View.ShaderMap->GetShader<FPostProcessVS>();
auto PixelShader = View.ShaderMap->GetShader<FFilterHistoryPS>(PermutationVector);
FVector2f MaxSampleBufferUV(
(AOViewSize.X - 0.5f - GAODownsampleFactor) / AOBufferSize.X,
(AOViewSize.Y - 0.5f - GAODownsampleFactor) / AOBufferSize.Y);
auto* PassParameters = GraphBuilder.AllocParameters<FFilterHistoryPS::FParameters>();
PassParameters->View = View.ViewUniformBuffer;
PassParameters->SceneTextures = SceneTextures.GetSceneTextureShaderParameters(View.FeatureLevel);;
PassParameters->BentNormalAOTexture = NewBentNormalHistory;
PassParameters->BentNormalAOSampler = TStaticSamplerState<SF_Bilinear, AM_Clamp, AM_Clamp, AM_Clamp>::GetRHI();
PassParameters->BentNormalAOTexelSize = FVector2f(1.0f / AOBufferSize.X, 1.0f / AOBufferSize.Y);
PassParameters->MaxSampleBufferUV = MaxSampleBufferUV;
PassParameters->HistoryWeight = GAOHistoryWeight;
PassParameters->RenderTargets[0] = FRenderTargetBinding(BentNormalHistoryTexture, ERenderTargetLoadAction::ELoad);
ClearUnusedGraphResources(PixelShader, PassParameters);
GraphBuilder.AddPass(
RDG_EVENT_NAME("UpdateHistoryStability"),
PassParameters,
ERDGPassFlags::Raster,
[PassParameters, VertexShader, PixelShader, &View, AOBufferSize, AOViewSize]
(FRDGAsyncTask, FRHICommandList& RHICmdList)
{
RHICmdList.SetViewport(0, 0, 0.0f, AOViewSize.X, AOViewSize.Y, 1.0f);
FGraphicsPipelineStateInitializer GraphicsPSOInit;
RHICmdList.ApplyCachedRenderTargets(GraphicsPSOInit);
GraphicsPSOInit.RasterizerState = TStaticRasterizerState<FM_Solid, CM_None>::GetRHI();
GraphicsPSOInit.DepthStencilState = TStaticDepthStencilState<false, CF_Always>::GetRHI();
GraphicsPSOInit.BlendState = TStaticBlendState<>::GetRHI();
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GFilterVertexDeclaration.VertexDeclarationRHI;
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit, 0);
SetShaderParameters(RHICmdList, PixelShader, PixelShader.GetPixelShader(), *PassParameters);
DrawRectangle(
RHICmdList,
0, 0,
AOViewSize.X, AOViewSize.Y,
0, 0,
AOViewSize.X, AOViewSize.Y,
AOViewSize ,
AOBufferSize,
VertexShader);
});
GraphBuilder.QueueTextureExtraction(BentNormalHistoryTexture, BentNormalHistoryState);
BentNormalHistoryOutput = BentNormalHistoryTexture;
}
else
{
// Update the view state's render target reference with the new history
GraphBuilder.QueueTextureExtraction(NewBentNormalHistory, BentNormalHistoryState);
BentNormalHistoryOutput = NewBentNormalHistory;
}
}
else
{
// Use the current frame's upscaled mask for next frame's history
FRDGTextureRef DistanceFieldAOBentNormal = nullptr;
AllocateOrReuseAORenderTarget(GraphBuilder, View, DistanceFieldAOBentNormal, TEXT("PerViewDistanceFieldBentNormalAO"), PF_FloatRGBA, GFastVRamConfig.DistanceFieldAOHistory);
GeometryAwareUpsample(GraphBuilder, View, DistanceFieldAOBentNormal, DistanceFieldNormal, BentNormalInterpolation, Parameters);
GraphBuilder.QueueTextureExtraction(DistanceFieldAOBentNormal, BentNormalHistoryState);
BentNormalHistoryOutput = DistanceFieldAOBentNormal;
}
DistanceFieldAOHistoryViewRect->Min = FIntPoint::ZeroValue;
DistanceFieldAOHistoryViewRect->Max = View.ViewRect.Size() / FIntPoint(GAODownsampleFactor, GAODownsampleFactor);
}
else
{
// Temporal reprojection is disabled or there is no view state - just upscale
FRDGTextureRef DistanceFieldAOBentNormal = nullptr;
AllocateOrReuseAORenderTarget(GraphBuilder, View, DistanceFieldAOBentNormal, TEXT("PerViewDistanceFieldBentNormalAO"), PF_FloatRGBA, GFastVRamConfig.DistanceFieldAOHistory);
GeometryAwareUpsample(GraphBuilder, View, DistanceFieldAOBentNormal, DistanceFieldNormal, BentNormalInterpolation, Parameters);
BentNormalHistoryOutput = DistanceFieldAOBentNormal;
}
}
class FDistanceFieldAOUpsamplePS : public FGlobalShader
{
public:
DECLARE_GLOBAL_SHADER(FDistanceFieldAOUpsamplePS);
SHADER_USE_PARAMETER_STRUCT(FDistanceFieldAOUpsamplePS, FGlobalShader);
BEGIN_SHADER_PARAMETER_STRUCT(FParameters, )
SHADER_PARAMETER_STRUCT_REF(FViewUniformShaderParameters, View)
SHADER_PARAMETER_STRUCT_INCLUDE(FSceneTextureShaderParameters, SceneTextures)
SHADER_PARAMETER_STRUCT_INCLUDE(FDFAOUpsampleParameters, DFAOUpsampleParameters)
SHADER_PARAMETER(float, MinIndirectDiffuseOcclusion)
RDG_TEXTURE_ACCESS(DistanceFieldAOBentNormal, ERHIAccess::SRVGraphics)
RENDER_TARGET_BINDING_SLOTS()
END_SHADER_PARAMETER_STRUCT()
class FModulateToSceneColorDim : SHADER_PERMUTATION_BOOL("MODULATE_SCENE_COLOR");
using FPermutationDomain = TShaderPermutationDomain<FModulateToSceneColorDim>;
static bool ShouldCompilePermutation(const FGlobalShaderPermutationParameters& Parameters)
{
return ShouldCompileDFLightingPostShaders(Parameters.Platform);
}
};
IMPLEMENT_GLOBAL_SHADER(FDistanceFieldAOUpsamplePS, "/Engine/Private/DistanceFieldLightingPost.usf", "AOUpsamplePS", SF_Pixel);
void UpsampleBentNormalAO(
FRDGBuilder& GraphBuilder,
const FViewInfo& View,
const FSceneTextures& SceneTextures,
FRDGTextureRef SceneColorTexture,
FRDGTextureRef DistanceFieldAOBentNormal,
bool bModulateSceneColor,
bool bModulateToScreenSpaceAO)
{
FScene* Scene = (FScene*)View.Family->Scene;
RDG_GPU_MASK_SCOPE(GraphBuilder, View.GPUMask);
auto* PassParameters = GraphBuilder.AllocParameters<FDistanceFieldAOUpsamplePS::FParameters>();
PassParameters->View = View.ViewUniformBuffer;
PassParameters->SceneTextures = SceneTextures.GetSceneTextureShaderParameters(View.FeatureLevel);;
PassParameters->DFAOUpsampleParameters = DistanceField::SetupAOUpsampleParameters(View, DistanceFieldAOBentNormal ? DistanceFieldAOBentNormal : GSystemTextures.GetWhiteDummy(GraphBuilder));
PassParameters->MinIndirectDiffuseOcclusion = Scene->SkyLight ? Scene->SkyLight->MinOcclusion : 0;
PassParameters->RenderTargets[0] = FRenderTargetBinding(SceneColorTexture, ERenderTargetLoadAction::ELoad);
PassParameters->DistanceFieldAOBentNormal = DistanceFieldAOBentNormal;
TShaderMapRef<FPostProcessVS> VertexShader(View.ShaderMap);
FDistanceFieldAOUpsamplePS::FPermutationDomain PermutationVector;
PermutationVector.Set<FDistanceFieldAOUpsamplePS::FModulateToSceneColorDim>(bModulateSceneColor || bModulateToScreenSpaceAO);
TShaderMapRef<FDistanceFieldAOUpsamplePS> PixelShader(View.ShaderMap, PermutationVector);
GraphBuilder.AddPass(
RDG_EVENT_NAME("UpsampleAO"),
PassParameters,
ERDGPassFlags::Raster,
[VertexShader, PixelShader, PassParameters, &View, DistanceFieldAOBentNormal, bModulateSceneColor, bModulateToScreenSpaceAO](FRDGAsyncTask, FRHICommandList& RHICmdList)
{
RHICmdList.SetViewport(View.ViewRect.Min.X, View.ViewRect.Min.Y, 0.0f, View.ViewRect.Max.X, View.ViewRect.Max.Y, 1.0f);
FGraphicsPipelineStateInitializer GraphicsPSOInit;
RHICmdList.ApplyCachedRenderTargets(GraphicsPSOInit);
GraphicsPSOInit.RasterizerState = TStaticRasterizerState<FM_Solid, CM_None>::GetRHI();
GraphicsPSOInit.DepthStencilState = TStaticDepthStencilState<false, CF_Always>::GetRHI();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
if (bModulateSceneColor || bModulateToScreenSpaceAO)
{
GraphicsPSOInit.BlendState = TStaticBlendState<CW_RGB, BO_Add, BF_DestColor, BF_Zero, BO_Add, BF_Zero, BF_One>::GetRHI();
}
else
{
GraphicsPSOInit.BlendState = TStaticBlendState<>::GetRHI();
}
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GFilterVertexDeclaration.VertexDeclarationRHI;
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader();
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit, 0);
SetShaderParameters(RHICmdList, PixelShader, PixelShader.GetPixelShader(), *PassParameters);
const int32 DownsampleFactor = bModulateToScreenSpaceAO ? 1.f : GAODownsampleFactor;
DrawRectangle(
RHICmdList,
0, 0,
View.ViewRect.Width(), View.ViewRect.Height(),
View.ViewRect.Min.X / DownsampleFactor, View.ViewRect.Min.Y / DownsampleFactor,
View.ViewRect.Width() / DownsampleFactor, View.ViewRect.Height() / DownsampleFactor,
FIntPoint(View.ViewRect.Width(), View.ViewRect.Height()),
GetBufferSizeForAO(View),
VertexShader);
});
}