#include "LumenScreenProbeGather.h"
#include "RendererPrivate.h"
#include "ScenePrivate.h"
#include "SceneUtils.h"
#include "PipelineStateCache.h"
#include "ShaderParameterStruct.h"
#include "PixelShaderUtils.h"
#include "LumenShortRangeAO.h"

Classes
class	FScreenSpaceShortRangeAOCS

Namespaces
namespace	LumenShortRangeAO

Functions
FAutoConsoleVariableRef	CVarLumenShortRangeAOSlopeCompareToleranceScale (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.SlopeCompareToleranceScale"), GLumenShortRangeAOSlopeCompareToleranceScale, TEXT("Scales the slope threshold that screen space traces use to determine whether there was a hit."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenMaxShortRangeAOMultibounceAlbedo (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.MaxMultibounceAlbedo"), GLumenMaxShortRangeAOMultibounceAlbedo, TEXT("Maximum albedo used for the AO multi-bounce approximation. Useful for forcing near-white albedo to have some occlusion."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	GVarLumenShortRangeAOHairStrandsVoxelTrace (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HairVoxelTrace"), GLumenShortRangeAOHairStrandsVoxelTrace, TEXT("Whether to trace against hair voxel structure for hair casting shadow onto opaques."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	GVarShortRangeAOHairStrandsScreenTrace (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HairScreenTrace"), GLumenShortRangeAOHairStrandsScreenTrace, TEXT("Whether to trace against hair depth for hair casting shadow onto opaques."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOScreenSpaceHorizonSearch (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch"), GLumenShortRangeAOScreenSpaceHorizonSearch, TEXT("1: Search the depth buffer along view space slices for the occluded horizon."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.VisibilityBitmask"), GLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask, TEXT("Whether to use a visibility bitmask for the horizon search instead of min/max horizon angles. This method has the potential to handle thin occluders better because it doesn't assume a continuous depth buffer."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOScreenSpaceHorizonSearchHZB (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.HZB"), GLumenShortRangeAOScreenSpaceHorizonSearchHZB, TEXT("Whether to use the Hierarchical ZBuffer instead of SceneDepth for occlusion. HZB is slightly faster to sample, especially with a larger AO radius, but loses detail on grass and thin occluders since it is half res depth."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOSliceCount (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.SliceCount"), GLumenShortRangeAOSliceCount, TEXT("Number of view space slices to search per pixel. This is a primary scalability control for Horizon ShortRangeAO."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOStepsPerSlice (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.StepsPerSlice"), GLumenShortRangeAOStepsPerSlice, TEXT("Number of horizon searching steps per view space slice. This is a primary scalability control for Horizon ShortRangeAO."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOForegroundSampleRejectDistanceFraction (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.ForegroundSampleRejectDistanceFraction"), GLumenShortRangeAOForegroundSampleRejectDistanceFraction, TEXT("Controls the Z distance away from the current pixel where neighboring pixels will be considered foreground and have their occlusion rejected, as a fraction of pixel depth."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeAOForegroundSampleRejectPower (TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.ForegroundSampleRejectPower"), GLumenShortRangeAOForegroundSampleRejectPower, TEXT("Controls how strongly foreground occluders contribute to final occlusion."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeGlobalIllumination (TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI"), GLumenShortRangeGlobalIllumination, TEXT("Whether to calculate and apply Short Range Global Illumination, on top of Ambient Occlusion. Experimental feature, not ready for production. "), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeGIHistoryDepthTestRelativeThickness (TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.HistoryDepthTestRelativeThickness"), GLumenShortRangeGIHistoryDepthTestRelativeThickness, TEXT("Distance between HZB trace hit and previous frame scene depth from which to allow hits, as a relative depth threshold."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeGIMaxScreenFraction (TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.MaxScreenFraction"), GLumenShortRangeGIMaxScreenFraction, TEXT("Trace distance for GI as a fraction of the screen size."), ECVF_Scalability\|ECVF_RenderThreadSafe)

FAutoConsoleVariableRef	CVarLumenShortRangeGIMaxRayIntensity (TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.MaxRayIntensity"), GLumenShortRangeGIMaxRayIntensity, TEXT("Maximum intensity of a single sample. Used to clamp fireflies, also loses lighting energy."), ECVF_Scalability\|ECVF_RenderThreadSafe)

bool	LumenShortRangeAO::ShouldApplyDuringIntegration ()

bool	LumenShortRangeAO::UseBentNormal ()

EPixelFormat	LumenShortRangeAO::GetTextureFormat ()

uint32	LumenShortRangeAO::GetRequestedDownsampleFactor ()

uint32	LumenShortRangeAO::GetDownsampleFactor ()

bool	LumenShortRangeAO::UseTemporal ()

float	LumenShortRangeAO::GetTemporalNeighborhoodClampScale ()

float	LumenShortRangeAO::GetFoliageOcclusionStrength ()

	IMPLEMENT_GLOBAL_SHADER (FScreenSpaceShortRangeAOCS, "/Engine/Private/Lumen/LumenScreenSpaceBentNormal.usf", "ScreenSpaceShortRangeAOCS", SF_Compute)

FLumenScreenSpaceBentNormalParameters	ComputeScreenSpaceShortRangeAO (FRDGBuilder &GraphBuilder, const FScene *Scene, const FViewInfo &View, const FLumenSceneFrameTemporaries &FrameTemporaries, const FSceneTextures &SceneTextures, FRDGTextureRef LightingChannelsTexture, const FBlueNoise &BlueNoise, FVector2f MaxScreenTraceFraction, float ScreenTraceNoFallbackThicknessScale, ERDGPassFlags ComputePassFlags)

Variables
float	GLumenShortRangeAOSlopeCompareToleranceScale = .5f

float	GLumenMaxShortRangeAOMultibounceAlbedo = .5f

int32	GLumenShortRangeAOHairStrandsVoxelTrace = 1

int32	GLumenShortRangeAOHairStrandsScreenTrace = 0

int32	GLumenShortRangeAOScreenSpaceHorizonSearch = 1

int32	GLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask = 0

int32	GLumenShortRangeAOScreenSpaceHorizonSearchHZB = 1

int32	GLumenShortRangeAOSliceCount = 2

int32	GLumenShortRangeAOStepsPerSlice = 3

float	GLumenShortRangeAOForegroundSampleRejectDistanceFraction = .3f

float	GLumenShortRangeAOForegroundSampleRejectPower = 1.0f

int32	GLumenShortRangeGlobalIllumination = 0

float	GLumenShortRangeGIHistoryDepthTestRelativeThickness = 0.0005f

float	GLumenShortRangeGIMaxScreenFraction = .1f

float	GLumenShortRangeGIMaxRayIntensity = 5.0f

Function Documentation

◆ ComputeScreenSpaceShortRangeAO()

FLumenScreenSpaceBentNormalParameters ComputeScreenSpaceShortRangeAO	(	FRDGBuilder &	GraphBuilder,
		const FScene *	Scene,
		const FViewInfo &	View,
		const FLumenSceneFrameTemporaries &	FrameTemporaries,
		const FSceneTextures &	SceneTextures,
		FRDGTextureRef	LightingChannelsTexture,
		const FBlueNoise &	BlueNoise,
		FVector2f	MaxScreenTraceFraction,
		float	ScreenTraceNoFallbackThicknessScale,
		ERDGPassFlags	ComputePassFlags
	)

◆ CVarLumenMaxShortRangeAOMultibounceAlbedo()

FAutoConsoleVariableRef CVarLumenMaxShortRangeAOMultibounceAlbedo	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.MaxMultibounceAlbedo")	,
		GLumenMaxShortRangeAOMultibounceAlbedo	,
		TEXT("Maximum albedo used for the AO multi-bounce approximation. Useful for forcing near-white albedo to have some occlusion.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOForegroundSampleRejectDistanceFraction()

FAutoConsoleVariableRef CVarLumenShortRangeAOForegroundSampleRejectDistanceFraction	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.ForegroundSampleRejectDistanceFraction")	,
		GLumenShortRangeAOForegroundSampleRejectDistanceFraction	,
		TEXT("Controls the Z distance away from the current pixel where neighboring pixels will be considered foreground and have their occlusion rejected, as a fraction of pixel depth.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOForegroundSampleRejectPower()

FAutoConsoleVariableRef CVarLumenShortRangeAOForegroundSampleRejectPower	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.ForegroundSampleRejectPower")	,
		GLumenShortRangeAOForegroundSampleRejectPower	,
		TEXT("Controls how strongly foreground occluders contribute to final occlusion.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOScreenSpaceHorizonSearch()

FAutoConsoleVariableRef CVarLumenShortRangeAOScreenSpaceHorizonSearch	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch")	,
		GLumenShortRangeAOScreenSpaceHorizonSearch	,
		TEXT("1: Search the depth buffer along view space slices for the occluded horizon.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOScreenSpaceHorizonSearchHZB()

FAutoConsoleVariableRef CVarLumenShortRangeAOScreenSpaceHorizonSearchHZB	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.HZB")	,
		GLumenShortRangeAOScreenSpaceHorizonSearchHZB	,
		TEXT("Whether to use the Hierarchical ZBuffer instead of SceneDepth for occlusion. HZB is slightly faster to sample, especially with a larger AO radius, but loses detail on grass and thin occluders since it is half res depth.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask()

FAutoConsoleVariableRef CVarLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.VisibilityBitmask")	,
		GLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask	,
		TEXT("Whether to use a visibility bitmask for the horizon search instead of min/max horizon angles. This method has the potential to handle thin occluders better because it doesn't assume a continuous depth buffer.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOSliceCount()

FAutoConsoleVariableRef CVarLumenShortRangeAOSliceCount	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.SliceCount")	,
		GLumenShortRangeAOSliceCount	,
		TEXT("Number of view space slices to search per pixel. This is a primary scalability control for Horizon ShortRangeAO.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOSlopeCompareToleranceScale()

FAutoConsoleVariableRef CVarLumenShortRangeAOSlopeCompareToleranceScale	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.SlopeCompareToleranceScale")	,
		GLumenShortRangeAOSlopeCompareToleranceScale	,
		TEXT("Scales the slope threshold that screen space traces use to determine whether there was a hit.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeAOStepsPerSlice()

FAutoConsoleVariableRef CVarLumenShortRangeAOStepsPerSlice	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HorizonSearch.StepsPerSlice")	,
		GLumenShortRangeAOStepsPerSlice	,
		TEXT("Number of horizon searching steps per view space slice. This is a primary scalability control for Horizon ShortRangeAO.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeGIHistoryDepthTestRelativeThickness()

FAutoConsoleVariableRef CVarLumenShortRangeGIHistoryDepthTestRelativeThickness	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.HistoryDepthTestRelativeThickness")	,
		GLumenShortRangeGIHistoryDepthTestRelativeThickness	,
		TEXT("Distance between HZB trace hit and previous frame scene depth from which to allow hits, as a relative depth threshold.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeGIMaxRayIntensity()

FAutoConsoleVariableRef CVarLumenShortRangeGIMaxRayIntensity	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.MaxRayIntensity")	,
		GLumenShortRangeGIMaxRayIntensity	,
		TEXT("Maximum intensity of a single sample. Used to clamp fireflies, also loses lighting energy.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeGIMaxScreenFraction()

FAutoConsoleVariableRef CVarLumenShortRangeGIMaxScreenFraction	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI.MaxScreenFraction")	,
		GLumenShortRangeGIMaxScreenFraction	,
		TEXT("Trace distance for GI as a fraction of the screen size.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ CVarLumenShortRangeGlobalIllumination()

FAutoConsoleVariableRef CVarLumenShortRangeGlobalIllumination	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeGI")	,
		GLumenShortRangeGlobalIllumination	,
		TEXT("Whether to calculate and apply Short Range Global Illumination, on top of Ambient Occlusion. Experimental feature, not ready for production. ")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ GVarLumenShortRangeAOHairStrandsVoxelTrace()

FAutoConsoleVariableRef GVarLumenShortRangeAOHairStrandsVoxelTrace	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HairVoxelTrace")	,
		GLumenShortRangeAOHairStrandsVoxelTrace	,
		TEXT("Whether to trace against hair voxel structure for hair casting shadow onto opaques.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ GVarShortRangeAOHairStrandsScreenTrace()

FAutoConsoleVariableRef GVarShortRangeAOHairStrandsScreenTrace	(	TEXT("r.Lumen.ScreenProbeGather.ShortRangeAO.HairScreenTrace")	,
		GLumenShortRangeAOHairStrandsScreenTrace	,
		TEXT("Whether to trace against hair depth for hair casting shadow onto opaques.")	,
		ECVF_Scalability\|	ECVF_RenderThreadSafe
	)

◆ IMPLEMENT_GLOBAL_SHADER()

IMPLEMENT_GLOBAL_SHADER	(	FScreenSpaceShortRangeAOCS	,
		"/Engine/Private/Lumen/LumenScreenSpaceBentNormal.usf"	,
		"ScreenSpaceShortRangeAOCS"	,
		SF_Compute
	)

Variable Documentation

◆ GLumenMaxShortRangeAOMultibounceAlbedo

float GLumenMaxShortRangeAOMultibounceAlbedo = .5f

◆ GLumenShortRangeAOForegroundSampleRejectDistanceFraction

float GLumenShortRangeAOForegroundSampleRejectDistanceFraction = .3f

◆ GLumenShortRangeAOForegroundSampleRejectPower

float GLumenShortRangeAOForegroundSampleRejectPower = 1.0f

◆ GLumenShortRangeAOHairStrandsScreenTrace

int32 GLumenShortRangeAOHairStrandsScreenTrace = 0

◆ GLumenShortRangeAOHairStrandsVoxelTrace

int32 GLumenShortRangeAOHairStrandsVoxelTrace = 1

◆ GLumenShortRangeAOScreenSpaceHorizonSearch

int32 GLumenShortRangeAOScreenSpaceHorizonSearch = 1

◆ GLumenShortRangeAOScreenSpaceHorizonSearchHZB

int32 GLumenShortRangeAOScreenSpaceHorizonSearchHZB = 1

◆ GLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask

int32 GLumenShortRangeAOScreenSpaceHorizonSearchVisibilityBitmask = 0

◆ GLumenShortRangeAOSliceCount

int32 GLumenShortRangeAOSliceCount = 2

◆ GLumenShortRangeAOSlopeCompareToleranceScale

float GLumenShortRangeAOSlopeCompareToleranceScale = .5f

◆ GLumenShortRangeAOStepsPerSlice

int32 GLumenShortRangeAOStepsPerSlice = 3

◆ GLumenShortRangeGIHistoryDepthTestRelativeThickness

float GLumenShortRangeGIHistoryDepthTestRelativeThickness = 0.0005f

◆ GLumenShortRangeGIMaxRayIntensity

float GLumenShortRangeGIMaxRayIntensity = 5.0f

◆ GLumenShortRangeGIMaxScreenFraction

float GLumenShortRangeGIMaxScreenFraction = .1f

◆ GLumenShortRangeGlobalIllumination

int32 GLumenShortRangeGlobalIllumination = 0

Classes

Namespaces

Functions

Variables