FRayTracingGeometryInstance | Unreal Engine 5.4 Documentation

References


Module	RHI
Header	/Engine/Source/Runtime/RHI/Public/RHIResources.h
Include	#include "RHIResources.h"

Syntax

struct FRayTracingGeometryInstance

Remarks

High level descriptor of one or more instances of a mesh in a ray tracing scene. All instances covered by this descriptor will share shader bindings, but may have different transforms and user data.

Variables

Type	Name	Description
TArrayView< const uint32 >	ActivationMask	Each geometry copy can have one bit to make it individually deactivated (removed from TLAS while maintaining hit group indexing).
bool	bApplyLocalBoundsTransform	Whether local bounds scale and center translation should be applied to the instance transform.
int32	BaseInstanceSceneDataOffset	Offsets into the scene's instance scene data buffer used to get instance transforms from GPUScene If BaseInstanceSceneDataOffset != -1, instances are assumed to be continuous.
uint32	DefaultUserData	Each geometry copy can receive a user-provided integer, which can be used to retrieve extra shader parameters or customize appearance.
ERayTracingInstanceFlags	Flags	Flags to control triangle back face culling, whether to allow any-hit shaders, etc.
FRHIRayTracingGeometry *	GeometryRHI
FShaderResourceViewRHIRef	GPUTransformsSRV	Optional buffer that stores GPU transforms. Used instead of CPU-side transform data.
TArrayView< const uint32 >	InstanceSceneDataOffsets
uint8	LayerIndex
uint8	Mask	Mask that will be tested against one provided to TraceRay() in shader code.
uint32	NumTransforms	Conservative number of instances.
TArrayView< const FMatrix >	Transforms	A single physical mesh may be duplicated many times in the scene with different transforms and user data.
TArrayView< const uint32 >	UserData

Constructors

	Type	Name	Description
	PRAGMA_DISABLE_DEPRECATION_WARNINGS	FRayTracingGeometryInstance ()
		FRayTracingGeometryInstance ( const FRayTracingGeometryInstance& )
		FRayTracingGeometryInstance ( FRayTracingGeometryInstance&& )