UE::Geometry::FMeshTriEdgeID Struct Reference

#include <InfoTypes.h>

Public Member Functions
	FMeshTriEdgeID ()
	FMeshTriEdgeID (int32 TriangleIDIn, int32 EdgeIndexIn)
	FMeshTriEdgeID (uint32 EncodedEdgeKey)
uint32	Encoded () const

Public Attributes
unsigned	TriEdgeIndex: 2
unsigned	TriangleID: 30

Detailed Description

FMeshTriEdgeID identifies an edge in a triangle mesh based on the triangle ID/Index and the "edge index" 0/1/2 in the triangle. If the ordered triangle vertices are [A,B,C], then [A,B]=0, [B,C]=1, and [C,A]=2.

This type of edge identifier is applicable on any indexed mesh, even if the mesh does not store explicit edge IDs.

Values are stored unsigned, so it is currently not possible to store an "invalid" edge identifier as a FMeshTriEdgeID (0xFFFFFFFF could potentially be used as such an identifier).

The TriangleID is stored in 30 bits, while FDynamicMesh3 stores (valid) triangle IDs in 31 bits. So, only ~1 billion triangles are allowed in a mesh when using FMeshTriEdgeID, vs ~2 billion in FDynamicMesh3. This limit has not been encountered in practice, to date.

Note that cycling or permuting the vertices of a triangle will change these indices.

Constructor & Destructor Documentation

FMeshTriEdgeID() [1/3]

UE::Geometry::FMeshTriEdgeID::FMeshTriEdgeID ( )

inline

FMeshTriEdgeID() [2/3]

UE::Geometry::FMeshTriEdgeID::FMeshTriEdgeID ( int32  TriangleIDIn, int32  EdgeIndexIn  )

inline

Construct a FMeshTriEdgeID for the given TriangleID and Edge Index in range

Parameters

EdgeIndexIn

index in range 0,1,2

FMeshTriEdgeID() [3/3]

UE::Geometry::FMeshTriEdgeID::FMeshTriEdgeID ( uint32  EncodedEdgeKey )

inlineexplicit

Decode an encoded FMeshTriEdgeID from a packed uint32 created by the Encoded() function

Member Function Documentation

Encoded()

uint32 UE::Geometry::FMeshTriEdgeID::Encoded ( ) const

inline

Returns

the (TriangleID, TriEdgeIndex) values packed into a 32 bit integer

Member Data Documentation

TriangleID

unsigned UE::Geometry::FMeshTriEdgeID::TriangleID

The index of the mesh Triangle

TriEdgeIndex

unsigned UE::Geometry::FMeshTriEdgeID::TriEdgeIndex

The 0/1/2 index of the edge in the triangle's tuple of edges

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The documentation for this struct was generated from the following file:

• Engine/Source/Runtime/GeometryCore/Public/DynamicMesh/InfoTypes.h