ContrastAdaptiveImageGenerator.cpp File Reference

#include "ContrastAdaptiveImageGenerator.h"
#include "StereoRenderTargetManager.h"
#include "GlobalShader.h"
#include "ShaderParameterUtils.h"
#include "RenderGraphUtils.h"
#include "RHI.h"
#include "RHIDefinitions.h"
#include "RenderTargetPool.h"
#include "SystemTextures.h"
#include "SceneRendering.h"
#include "SceneTextures.h"
#include "SceneView.h"
#include "IEyeTracker.h"
#include "IHeadMountedDisplay.h"
#include "IXRTrackingSystem.h"
#include "Engine/Engine.h"
#include "UnrealClient.h"
#include "PostProcess/PostProcessTonemap.h"
#include "DataDrivenShaderPlatformInfo.h"

Classes
class	FCalculateShadingRateImageCS
class	FRescaleVariableRateShadingCS
struct	FCASImageData
struct	FCASImageData::FCASImageSet

Namespaces
namespace	ESRITextureType
namespace	ESRIPreviewType

Functions
	IMPLEMENT_GLOBAL_SHADER (FCalculateShadingRateImageCS, "/Engine/Private/VariableRateShading/VRSShadingRateCalculate.usf", "CalculateShadingRateImage", SF_Compute)
	IMPLEMENT_GLOBAL_SHADER (FRescaleVariableRateShadingCS, "/Engine/Private/VariableRateShading/VRSShadingRateReproject.usf", "RescaleVariableRateShading", SF_Compute)
	RDG_REGISTER_BLACKBOARD_STRUCT (FCASImageData)
void	AddCreateShadingRateImagePass (FRDGBuilder &GraphBuilder, const FSceneViewFamily &ViewFamily, bool bCreateHardwareImages, bool bCreateSoftwareImages)
void	AddReprojectImageBasedVRSPass (FRDGBuilder &GraphBuilder, const FMinimalSceneTextures &SceneTextures, const FSceneViewFamily &ViewFamily, bool bReprojectSoftwareImages)

Variables
TAutoConsoleVariable< int32 >	CVarCASContrastAdaptiveShading (TEXT("r.VRS.ContrastAdaptiveShading"), 0, TEXT("Enables using Variable Rate Shading based on the luminance from the previous frame's post process output \n"), ECVF_RenderThreadSafe)
TAutoConsoleVariable< float >	CVarCASEdgeThreshold (TEXT("r.VRS.ContrastAdaptiveShading.EdgeThreshold"), 0.2, TEXT(""), ECVF_RenderThreadSafe)
TAutoConsoleVariable< float >	CVarCASConservativeEdgeThreshold (TEXT("r.VRS.ContrastAdaptiveShading.ConservativeEdgeThreshold"), 0.1, TEXT(""), ECVF_RenderThreadSafe)
TAutoConsoleVariable< float >	CVarCAS_HDR10CorrectionMultiplier (TEXT("r.VRS.ContrastAdaptiveShading.HDR10CorrectionMultiplier"), 0.55, TEXT("Approximation multiplier to account for how perceptual values are spread out in SDR vs HDR10\n"), ECVF_RenderThreadSafe)
TAutoConsoleVariable< int32 >	CVarCASPreview (TEXT("r.VRS.ContrastAdaptiveShading.Preview"), 1, TEXT("0 - off, 1 - on (default)"), ECVF_RenderThreadSafe)

Function Documentation

AddCreateShadingRateImagePass()

void AddCreateShadingRateImagePass	(	FRDGBuilder &	GraphBuilder,
		const FSceneViewFamily &	ViewFamily,
		bool	bCreateHardwareImages,
		bool	bCreateSoftwareImages
	)

AddReprojectImageBasedVRSPass()

void AddReprojectImageBasedVRSPass	(	FRDGBuilder &	GraphBuilder,
		const FMinimalSceneTextures &	SceneTextures,
		const FSceneViewFamily &	ViewFamily,
		bool	bReprojectSoftwareImages
	)

IMPLEMENT_GLOBAL_SHADER() [1/2]

IMPLEMENT_GLOBAL_SHADER	(	FCalculateShadingRateImageCS	,
		"/Engine/Private/VariableRateShading/VRSShadingRateCalculate.usf"	,
		"CalculateShadingRateImage"	,
		SF_Compute
	)

IMPLEMENT_GLOBAL_SHADER() [2/2]

IMPLEMENT_GLOBAL_SHADER	(	FRescaleVariableRateShadingCS	,
		"/Engine/Private/VariableRateShading/VRSShadingRateReproject.usf"	,
		"RescaleVariableRateShading"	,
		SF_Compute
	)

RDG_REGISTER_BLACKBOARD_STRUCT()

RDG_REGISTER_BLACKBOARD_STRUCT

(

FCASImageData

)

Variable Documentation

CVarCAS_HDR10CorrectionMultiplier

TAutoConsoleVariable< float > CVarCAS_HDR10CorrectionMultiplier(TEXT("r.VRS.ContrastAdaptiveShading.HDR10CorrectionMultiplier"), 0.55, TEXT("Approximation multiplier to account for how perceptual values are spread out in SDR vs HDR10\n"), ECVF_RenderThreadSafe)	(	TEXT("r.VRS.ContrastAdaptiveShading.HDR10CorrectionMultiplier")	,
		0.	55,
		TEXT("Approximation multiplier to account for how perceptual values are spread out in SDR vs HDR10\n")	,
		ECVF_RenderThreadSafe
	)

CVarCASConservativeEdgeThreshold

TAutoConsoleVariable< float > CVarCASConservativeEdgeThreshold(TEXT("r.VRS.ContrastAdaptiveShading.ConservativeEdgeThreshold"), 0.1, TEXT(""), ECVF_RenderThreadSafe)	(	TEXT("r.VRS.ContrastAdaptiveShading.ConservativeEdgeThreshold")	,
		0.	1,
		TEXT("")	,
		ECVF_RenderThreadSafe
	)

CVarCASContrastAdaptiveShading

TAutoConsoleVariable< int32 > CVarCASContrastAdaptiveShading(TEXT("r.VRS.ContrastAdaptiveShading"), 0, TEXT("Enables using Variable Rate Shading based on the luminance from the previous frame's post process output \n"), ECVF_RenderThreadSafe)	(	TEXT("r.VRS.ContrastAdaptiveShading")	,
		0	,
		TEXT("Enables using Variable Rate Shading based on the luminance from the previous frame's post process output \n")	,
		ECVF_RenderThreadSafe
	)

Contrast Adaptive Shading (CAS) is a Tier 2 Variable Rate Shading method which generates a shading rate image (SRI) by examining the contrast from the previous frame. An image is generated which designates lower shading rates for areas of lower contrast in which reductions are unlikely to be noticed. This image is then reprojected and rescaled in accordance with camera movement and dynamic resolution changes before being provided to the manager. CAS Parameters

CVarCASEdgeThreshold

TAutoConsoleVariable< float > CVarCASEdgeThreshold(TEXT("r.VRS.ContrastAdaptiveShading.EdgeThreshold"), 0.2, TEXT(""), ECVF_RenderThreadSafe)	(	TEXT("r.VRS.ContrastAdaptiveShading.EdgeThreshold")	,
		0.	2,
		TEXT("")	,
		ECVF_RenderThreadSafe
	)

CVarCASPreview

TAutoConsoleVariable< int32 > CVarCASPreview(TEXT("r.VRS.ContrastAdaptiveShading.Preview"), 1, TEXT("0 - off, 1 - on (default)"), ECVF_RenderThreadSafe)	(	TEXT("r.VRS.ContrastAdaptiveShading.Preview")	,
		1	,
		TEXT("0 - off, 1 - on (default)")	,
		ECVF_RenderThreadSafe
	)

Debug Settings