TCachingMeshSDF | Unreal Engine 5.2 Documentation

API > API/Runtime > API/Runtime/GeometryCore > API/Runtime/GeometryCore/Implicit

References


Module	GeometryCore
Header	/Engine/Source/Runtime/GeometryCore/Public/Implicit/CachingMeshSDF.h
Include	#include "Implicit/CachingMeshSDF.h"

Syntax

template<class TriangleMeshType>  
class TCachingMeshSDF

Remarks

This is variant of TSweepingMeshSDF that does lazy evaluation of actual Distances, using mesh spatial data structure. This is much faster if we are doing continuation-method marching cubes as only values on surface will be computed!

Compute discretely-sampled (I.e. gridded) signed distance field for a mesh only within a narrow band of the surface (within MaxDistQueryDist = MaxOffsetDistance + (2 * CellSize * FMathf::Sqrt2))

This code is based on the implementation found at https://github.com/christopherbatty/SDFGen

Variables

Type	Name	Description
int	ApproxMaxCellsPerDimension	If the number of cells in any dimension may exceed this, CellSize will be automatically increased to keep cell count reasonable.
bool	bComputeSigns	Should we try to compute signs? if not, Grid remains unsigned
bool	bUseParallel	Most of this parallelizes very well, makes a huge speed difference.
bool	bWantClosestTriGrid	Implementation computes the triangle closest to each Grid cell, can return this Grid if desired (only reason not to is avoid hanging onto memory)
bool	bWantIntersectionsGrid	Grid of per-cell crossing or parity counts.
TFunction< bool(void)>	CancelF	If this function returns true, we should abort calculation
float	CellSize
FDenseGrid3i	ClosestTriGrid
FVector3d	ExpandBounds	Bounds of Grid will be expanded this much in positive and negative directions.
FDenseGrid3f	Grid
FVector3f	GridOrigin
EInsideModes	InsideMode
FDenseGrid3i	IntersectionsGrid
double	MaxDistQueryDist
float	MaxOffsetDistance	Max distance away from surface that we might need to evaluate
const TriangleMeshType *	Mesh
const TMeshAABBTree3< TriangleMeshType > *	Spatial
float	UpperBoundDistance

Constructors

	Type	Name	Description
		TCachingMeshSDF ( float CellSizeIn )
		TCachingMeshSDF ( const TriangleMeshType* MeshIn, float CellSizeIn, const TMeshAABBTree3< TriangleMeshType >* SpatialIn, bool bAutoBuild )

Functions

Type	Name	Description
float	At ( int I, int J, int K )
FVector3f	CellCenter ( int I, int J, int K )
void	CleanupUnwanted ()
FVector3i	Dimensions ()
const FDenseGrid3i &	GetClosestTriGrid ()
const FDenseGrid3f &	GetGrid ()	SDF Grid available after calling Compute()
const FVector3f &	GetGridOrigin ()	Origin of the SDF Grid, in same coordinates as mesh
const FDenseGrid3i &	GetIntersectionsGrid ()
float	GetValue ( FVector3i Idx )
void	Initialize ()
TTriLinearGridInterpolant< TCachingMeshSDF >	MakeInterpolant ()
int	Orientation ( double X1, double Y1, double X2, double Y2, double& TwiceSignedArea )	Calculate twice signed area of triangle (0,0)-(X1,Y1)-(X2,Y2) return an SOS-determined sign (-1, +1, or 0 only if it's a truly degenerate triangle)
bool	PointInTriangle2d ( double X0, double Y0, double X1, double Y1, double X2, double Y2, double X3, double Y3, double& A, double& B, double& C )	Robust test of (X0,Y0) in the triangle (X1,Y1)-(X2,Y2)-(X3,Y3) if true is returned, the barycentric coordinates are set in A,B,C.
bool	Validate ()