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UnrealEngineUWP/Engine/Source/Runtime/Renderer/Private/DecalRenderingShared.cpp
Andrew Davidson 3ddc3a4da3 Merge up from //UE5/Dev-LargeWorldCoordinates
#rb none

[CL 16211417 by Andrew Davidson in ue5-main branch]
2021-05-05 15:07:25 -04:00

437 lines
18 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
/*=============================================================================
DecalRenderingShared.cpp
=============================================================================*/
#include "DecalRenderingShared.h"
#include "StaticBoundShaderState.h"
#include "Components/DecalComponent.h"
#include "GlobalShader.h"
#include "MaterialShaderType.h"
#include "MaterialShader.h"
#include "DebugViewModeRendering.h"
#include "ScenePrivate.h"
#include "PipelineStateCache.h"
static TAutoConsoleVariable<float> CVarDecalFadeScreenSizeMultiplier(
TEXT("r.Decal.FadeScreenSizeMult"),
1.0f,
TEXT("Control the per decal fade screen size. Multiplies with the per-decal screen size fade threshold.")
TEXT(" Smaller means decals fade less aggressively.")
);
FTransientDecalRenderData::FTransientDecalRenderData(const FScene& InScene, const FDeferredDecalProxy* InDecalProxy, float InConservativeRadius)
: DecalProxy(InDecalProxy)
, FadeAlpha(1.0f)
, ConservativeRadius(InConservativeRadius)
{
MaterialProxy = InDecalProxy->DecalMaterial->GetRenderProxy();
MaterialResource = &MaterialProxy->GetMaterialWithFallback(InScene.GetFeatureLevel(), MaterialProxy);
check(MaterialProxy && MaterialResource);
DecalBlendDesc = DecalRendering::ComputeDecalBlendDesc(InScene.GetShaderPlatform(), MaterialResource);
}
/**
* A vertex shader for projecting a deferred decal onto the scene.
*/
class FDeferredDecalVS : public FGlobalShader
{
DECLARE_SHADER_TYPE(FDeferredDecalVS,Global);
public:
static bool ShouldCompilePermutation(const FGlobalShaderPermutationParameters& Parameters)
{
return true;
}
FDeferredDecalVS( ) { }
FDeferredDecalVS(const ShaderMetaType::CompiledShaderInitializerType& Initializer)
: FGlobalShader(Initializer)
{
FrustumComponentToClip.Bind(Initializer.ParameterMap, TEXT("FrustumComponentToClip"));
}
void SetParameters(FRHICommandList& RHICmdList, const FMatrix44f& InFrustumComponentToClip)
{
FRHIVertexShader* ShaderRHI = RHICmdList.GetBoundVertexShader();
SetShaderValue(RHICmdList, ShaderRHI, FrustumComponentToClip, InFrustumComponentToClip);
}
private:
LAYOUT_FIELD(FShaderParameter, FrustumComponentToClip);
};
IMPLEMENT_SHADER_TYPE(,FDeferredDecalVS,TEXT("/Engine/Private/DeferredDecal.usf"),TEXT("MainVS"),SF_Vertex);
/**
* A pixel shader for projecting a deferred decal onto the scene.
*/
class FDeferredDecalPS : public FMaterialShader
{
DECLARE_SHADER_TYPE(FDeferredDecalPS,Material);
public:
static bool ShouldCompilePermutation(const FMaterialShaderPermutationParameters& Parameters)
{
return (Parameters.MaterialParameters.MaterialDomain == MD_DeferredDecal) &&
DecalRendering::GetBaseRenderStage(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters)) != EDecalRenderStage::None;
}
static void ModifyCompilationEnvironment(const FMaterialShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
FMaterialShader::ModifyCompilationEnvironment(Parameters, OutEnvironment);
DecalRendering::ModifyCompilationEnvironment(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters), EDecalRenderStage::None, OutEnvironment);
}
FDeferredDecalPS() {}
FDeferredDecalPS(const ShaderMetaType::CompiledShaderInitializerType& Initializer)
: FMaterialShader(Initializer)
{
SvPositionToDecal.Bind(Initializer.ParameterMap,TEXT("SvPositionToDecal"));
DecalToWorld.Bind(Initializer.ParameterMap,TEXT("DecalToWorld"));
WorldToDecal.Bind(Initializer.ParameterMap,TEXT("WorldToDecal"));
DecalOrientation.Bind(Initializer.ParameterMap,TEXT("DecalOrientation"));
DecalParams.Bind(Initializer.ParameterMap, TEXT("DecalParams"));
}
void SetParameters(FRHICommandList& RHICmdList, const FViewInfo& View, const FMaterialRenderProxy* MaterialProxy, const FDeferredDecalProxy& DecalProxy, const float FadeAlphaValue=1.0f)
{
FRHIPixelShader* ShaderRHI = RHICmdList.GetBoundPixelShader();
const FMaterialRenderProxy* MaterialProxyForRendering = MaterialProxy;
const FMaterial& Material = MaterialProxy->GetMaterialWithFallback(View.GetFeatureLevel(), MaterialProxyForRendering);
FMaterialShader::SetParameters(RHICmdList, ShaderRHI, MaterialProxyForRendering, Material, View);
FTransform ComponentTrans = DecalProxy.ComponentTrans;
FMatrix44f WorldToComponent = ComponentTrans.ToInverseMatrixWithScale();
// Set the transform from screen space to light space.
if(SvPositionToDecal.IsBound())
{
FVector2D InvViewSize = FVector2D(1.0f / View.ViewRect.Width(), 1.0f / View.ViewRect.Height());
// setup a matrix to transform float4(SvPosition.xyz,1) directly to Decal (quality, performance as we don't need to convert or use interpolator)
// new_xy = (xy - ViewRectMin.xy) * ViewSizeAndInvSize.zw * float2(2,-2) + float2(-1, 1);
// transformed into one MAD: new_xy = xy * ViewSizeAndInvSize.zw * float2(2,-2) + (-ViewRectMin.xy) * ViewSizeAndInvSize.zw * float2(2,-2) + float2(-1, 1);
float Mx = 2.0f * InvViewSize.X;
float My = -2.0f * InvViewSize.Y;
float Ax = -1.0f - 2.0f * View.ViewRect.Min.X * InvViewSize.X;
float Ay = 1.0f + 2.0f * View.ViewRect.Min.Y * InvViewSize.Y;
// todo: we could use InvTranslatedViewProjectionMatrix and TranslatedWorldToComponent for better quality
const FMatrix44f SvPositionToDecalValue =
FMatrix(
FPlane(Mx, 0, 0, 0),
FPlane( 0, My, 0, 0),
FPlane( 0, 0, 1, 0),
FPlane(Ax, Ay, 0, 1)
) * View.ViewMatrices.GetInvViewProjectionMatrix() * WorldToComponent;
SetShaderValue(RHICmdList, ShaderRHI, SvPositionToDecal, SvPositionToDecalValue);
}
// Set the transform from light space to world space
if(DecalToWorld.IsBound())
{
const FMatrix44f DecalToWorldValue = ComponentTrans.ToMatrixWithScale();
SetShaderValue(RHICmdList, ShaderRHI, DecalToWorld, DecalToWorldValue);
}
SetShaderValue(RHICmdList, ShaderRHI, WorldToDecal, WorldToComponent);
if (DecalOrientation.IsBound())
{
// can get DecalOrientation form DecalToWorld matrix, but it will require binding whole matrix and normalizing axis in the shader
SetShaderValue(RHICmdList, ShaderRHI, DecalOrientation, FVector3f(ComponentTrans.GetUnitAxis(EAxis::X)));
}
float LifetimeAlpha = 1.0f;
// Certain engine captures (e.g. environment reflection) don't have a tick. Default to fully opaque.
if (View.Family->CurrentWorldTime)
{
LifetimeAlpha = FMath::Clamp(FMath::Min(View.Family->CurrentWorldTime * -DecalProxy.InvFadeDuration + DecalProxy.FadeStartDelayNormalized, View.Family->CurrentWorldTime * DecalProxy.InvFadeInDuration + DecalProxy.FadeInStartDelayNormalized), 0.0f, 1.0f);
}
SetShaderValue(RHICmdList, ShaderRHI, DecalParams, FVector2D(FadeAlphaValue, LifetimeAlpha));
}
private:
LAYOUT_FIELD(FShaderParameter, SvPositionToDecal);
LAYOUT_FIELD(FShaderParameter, DecalToWorld);
LAYOUT_FIELD(FShaderParameter, WorldToDecal);
LAYOUT_FIELD(FShaderParameter, DecalOrientation);
LAYOUT_FIELD(FShaderParameter, DecalParams);
};
IMPLEMENT_MATERIAL_SHADER_TYPE(,FDeferredDecalPS,TEXT("/Engine/Private/DeferredDecal.usf"),TEXT("MainPS"),SF_Pixel);
class FDeferredDecalEmissivePS : public FDeferredDecalPS
{
DECLARE_SHADER_TYPE(FDeferredDecalEmissivePS, Material);
public:
static bool ShouldCompilePermutation(const FMaterialShaderPermutationParameters& Parameters)
{
return (Parameters.MaterialParameters.MaterialDomain == MD_DeferredDecal) &&
DecalRendering::IsCompatibleWithRenderStage(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters), EDecalRenderStage::Emissive);
}
static void ModifyCompilationEnvironment(const FMaterialShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
FMaterialShader::ModifyCompilationEnvironment(Parameters, OutEnvironment);
DecalRendering::ModifyCompilationEnvironment(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters), EDecalRenderStage::Emissive, OutEnvironment);
}
FDeferredDecalEmissivePS() {}
FDeferredDecalEmissivePS(const ShaderMetaType::CompiledShaderInitializerType& Initializer)
: FDeferredDecalPS(Initializer)
{}
};
IMPLEMENT_MATERIAL_SHADER_TYPE(, FDeferredDecalEmissivePS, TEXT("/Engine/Private/DeferredDecal.usf"), TEXT("MainPS"), SF_Pixel);
class FDeferredDecalAmbientOcclusionPS : public FDeferredDecalPS
{
DECLARE_SHADER_TYPE(FDeferredDecalAmbientOcclusionPS, Material);
public:
static bool ShouldCompilePermutation(const FMaterialShaderPermutationParameters& Parameters)
{
return (Parameters.MaterialParameters.MaterialDomain == MD_DeferredDecal) &&
DecalRendering::IsCompatibleWithRenderStage(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters), EDecalRenderStage::AmbientOcclusion);
}
static void ModifyCompilationEnvironment(const FMaterialShaderPermutationParameters& Parameters, FShaderCompilerEnvironment& OutEnvironment)
{
FMaterialShader::ModifyCompilationEnvironment(Parameters, OutEnvironment);
DecalRendering::ModifyCompilationEnvironment(DecalRendering::ComputeDecalBlendDesc(Parameters.Platform, Parameters.MaterialParameters), EDecalRenderStage::AmbientOcclusion, OutEnvironment);
}
FDeferredDecalAmbientOcclusionPS() {}
FDeferredDecalAmbientOcclusionPS(const ShaderMetaType::CompiledShaderInitializerType& Initializer)
: FDeferredDecalPS(Initializer)
{}
};
IMPLEMENT_MATERIAL_SHADER_TYPE(, FDeferredDecalAmbientOcclusionPS, TEXT("/Engine/Private/DeferredDecal.usf"), TEXT("MainPS"), SF_Pixel);
namespace DecalRendering
{
bool BuildVisibleDecalList(const FScene& Scene, const FViewInfo& View, EDecalRenderStage DecalRenderStage, FTransientDecalRenderDataList* OutVisibleDecals)
{
QUICK_SCOPE_CYCLE_COUNTER(BuildVisibleDecalList);
if (OutVisibleDecals)
{
OutVisibleDecals->Empty(Scene.Decals.Num());
}
// Don't draw for shader complexity mode.
// todo: Handle shader complexity mode for deferred decal.
if (View.Family->EngineShowFlags.ShaderComplexity)
{
return false;
}
const float FadeMultiplier = CVarDecalFadeScreenSizeMultiplier.GetValueOnRenderThread();
const EShaderPlatform ShaderPlatform = View.GetShaderPlatform();
const bool bIsPerspectiveProjection = View.IsPerspectiveProjection();
// Build a list of decals that need to be rendered for this view in SortedDecals
for (const FDeferredDecalProxy* DecalProxy : Scene.Decals)
{
if (!DecalProxy->DecalMaterial || !DecalProxy->DecalMaterial->IsValidLowLevelFast())
{
continue;
}
bool bIsShown = true;
if (!DecalProxy->IsShown(&View))
{
bIsShown = false;
}
const FMatrix ComponentToWorldMatrix = DecalProxy->ComponentTrans.ToMatrixWithScale();
// can be optimized as we test against a sphere around the box instead of the box itself
const float ConservativeRadius = FMath::Sqrt(
ComponentToWorldMatrix.GetScaledAxis(EAxis::X).SizeSquared() +
ComponentToWorldMatrix.GetScaledAxis(EAxis::Y).SizeSquared() +
ComponentToWorldMatrix.GetScaledAxis(EAxis::Z).SizeSquared());
// can be optimized as the test is too conservative (sphere instead of OBB)
if(ConservativeRadius < SMALL_NUMBER || !View.ViewFrustum.IntersectSphere(ComponentToWorldMatrix.GetOrigin(), ConservativeRadius))
{
bIsShown = false;
}
if (bIsShown)
{
FTransientDecalRenderData Data(Scene, DecalProxy, ConservativeRadius);
if (IsCompatibleWithRenderStage(Data.DecalBlendDesc, DecalRenderStage))
{
if (bIsPerspectiveProjection && Data.DecalProxy->FadeScreenSize != 0.0f)
{
float Distance = (View.ViewMatrices.GetViewOrigin() - ComponentToWorldMatrix.GetOrigin()).Size();
float Radius = ComponentToWorldMatrix.GetMaximumAxisScale();
float CurrentScreenSize = ((Radius / Distance) * FadeMultiplier);
// fading coefficient needs to increase with increasing field of view and decrease with increasing resolution
// FadeCoeffScale is an empirically determined constant to bring us back roughly to fraction of screen size for FadeScreenSize
const float FadeCoeffScale = 600.0f;
float FOVFactor = ((2.0f/View.ViewMatrices.GetProjectionMatrix().M[0][0]) / View.ViewRect.Width()) * FadeCoeffScale;
float FadeCoeff = Data.DecalProxy->FadeScreenSize * FOVFactor;
float FadeRange = FadeCoeff * 0.5f;
float Alpha = (CurrentScreenSize - FadeCoeff) / FadeRange;
Data.FadeAlpha = FMath::Min(Alpha, 1.0f);
}
const bool bShouldRender = Data.FadeAlpha > 0.0f;
if (bShouldRender)
{
if (!OutVisibleDecals)
{
return true;
}
OutVisibleDecals->Add(Data);
}
}
}
}
if (!OutVisibleDecals)
{
return false;
}
if (OutVisibleDecals->Num() > 0)
{
// Sort by sort order to allow control over composited result
// Then sort decals by state to reduce render target switches
// Also sort by component since Sort() is not stable
struct FCompareFTransientDecalRenderData
{
FORCEINLINE bool operator()(const FTransientDecalRenderData& A, const FTransientDecalRenderData& B) const
{
if (B.DecalProxy->SortOrder != A.DecalProxy->SortOrder)
{
return A.DecalProxy->SortOrder < B.DecalProxy->SortOrder;
}
if (B.DecalBlendDesc.bWriteNormal != A.DecalBlendDesc.bWriteNormal)
{
// bWriteNormal here has priority because we want to render decals that output normals before those could read normals.
// Also this is the only flag that can trigger a change of EDecalRenderTargetMode inside a single EDecalRenderStage, and we batch according to this.
return B.DecalBlendDesc.bWriteNormal < A.DecalBlendDesc.bWriteNormal; // < so that those outputting normal are first.
}
if (B.DecalBlendDesc.Packed != A.DecalBlendDesc.Packed)
{
// Sorting by the FDecalBlendDesc contents will reduce blend state changes.
return (int32)B.DecalBlendDesc.Packed < (int32)A.DecalBlendDesc.Packed;
}
if (B.MaterialProxy != A.MaterialProxy)
{
// Batch decals with the same material together
return B.MaterialProxy < A.MaterialProxy;
}
return (PTRINT)B.DecalProxy->Component < (PTRINT)A.DecalProxy->Component;
}
};
// Sort decals by blend mode to reduce render target switches
OutVisibleDecals->Sort(FCompareFTransientDecalRenderData());
return true;
}
return false;
}
FMatrix ComputeComponentToClipMatrix(const FViewInfo& View, const FMatrix& DecalComponentToWorld)
{
FMatrix ComponentToWorldMatrixTrans = DecalComponentToWorld.ConcatTranslation(View.ViewMatrices.GetPreViewTranslation());
return ComponentToWorldMatrixTrans * View.ViewMatrices.GetTranslatedViewProjectionMatrix();
}
void SetShader(FRHICommandList& RHICmdList, FGraphicsPipelineStateInitializer& GraphicsPSOInit, const FViewInfo& View,
const FTransientDecalRenderData& DecalData, EDecalRenderStage DecalRenderStage, const FMatrix& FrustumComponentToClip)
{
const FMaterialShaderMap* MaterialShaderMap = DecalData.MaterialResource->GetRenderingThreadShaderMap();
const EDebugViewShaderMode DebugViewMode = View.Family->GetDebugViewShaderMode();
// When in shader complexity, decals get rendered as emissive even though there might not be emissive decals.
// FDeferredDecalEmissivePS might not be available depending on the decal blend mode.
TShaderRef<FDeferredDecalPS> PixelShader;
if (DecalRenderStage == EDecalRenderStage::Emissive || DebugViewMode != DVSM_None)
{
PixelShader = TShaderRef<FDeferredDecalPS>(MaterialShaderMap->GetShader<FDeferredDecalEmissivePS>());
}
else if (DecalRenderStage == EDecalRenderStage::AmbientOcclusion)
{
PixelShader = TShaderRef<FDeferredDecalPS>(MaterialShaderMap->GetShader<FDeferredDecalAmbientOcclusionPS>());
}
else
{
PixelShader = MaterialShaderMap->GetShader<FDeferredDecalPS>();
}
TShaderMapRef<FDeferredDecalVS> VertexShader(View.ShaderMap);
{
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GetVertexDeclarationFVector4();
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.BoundShaderState.PixelShaderRHI = PixelShader.GetPixelShader();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit);
PixelShader->SetParameters(RHICmdList, View, DecalData.MaterialProxy, *DecalData.DecalProxy, DecalData.FadeAlpha);
}
// SetUniformBufferParameter() need to happen after the shader has been set otherwise a DebugBreak could occur.
// we don't have the Primitive uniform buffer setup for decals (later we want to batch)
{
auto& PrimitiveVS = VertexShader->GetUniformBufferParameter<FPrimitiveUniformShaderParameters>();
auto& PrimitivePS = PixelShader->GetUniformBufferParameter<FPrimitiveUniformShaderParameters>();
// uncomment to track down usage of the Primitive uniform buffer
// check(!PrimitiveVS.IsBound());
// check(!PrimitivePS.IsBound());
// to prevent potential shader error (UE-18852 ElementalDemo crashes due to nil constant buffer)
SetUniformBufferParameter(RHICmdList, VertexShader.GetVertexShader(), PrimitiveVS, GIdentityPrimitiveUniformBuffer);
if (DebugViewMode == DVSM_None)
{
SetUniformBufferParameter(RHICmdList, PixelShader.GetPixelShader(), PrimitivePS, GIdentityPrimitiveUniformBuffer);
}
}
VertexShader->SetParameters(RHICmdList, FrustumComponentToClip);
// Set stream source after updating cached strides
RHICmdList.SetStreamSource(0, GetUnitCubeVertexBuffer(), 0);
}
void SetVertexShaderOnly(FRHICommandList& RHICmdList, FGraphicsPipelineStateInitializer& GraphicsPSOInit, const FViewInfo& View, const FMatrix& FrustumComponentToClip)
{
TShaderMapRef<FDeferredDecalVS> VertexShader(View.ShaderMap);
GraphicsPSOInit.BoundShaderState.VertexDeclarationRHI = GetVertexDeclarationFVector4();
GraphicsPSOInit.BoundShaderState.VertexShaderRHI = VertexShader.GetVertexShader();
GraphicsPSOInit.PrimitiveType = PT_TriangleList;
SetGraphicsPipelineState(RHICmdList, GraphicsPSOInit);
VertexShader->SetParameters(RHICmdList, FrustumComponentToClip);
}
}