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FDynamicMeshEditor

[FDynamicMeshEditor](API\Runtime\GeometryCore\FDynamicMeshEditor) implements low-level mesh editing operations.

API > API/Runtime > API/Runtime/GeometryCore

FDynamicMeshEditor implements low-level mesh editing operations. These operations can be used to construct higher-level operations. For example an Extrude operation could be implemented via DuplicateTriangles() and StitchLoopMinimal().

   
Name FDynamicMeshEditor
Type class
Header File /Engine/Source/Runtime/GeometryCore/Public/DynamicMeshEditor.h
Include Path #include "DynamicMeshEditor.h"

Syntax

class FDynamicMeshEditor

Constructors

Name Remarks Include Path Unreal Specifiers

FDynamicMeshEditor ( FDynamicMesh3* MeshIn
)

   DynamicMeshEditor.h  

Structs

Name Remarks
FLoopPairSet Pair of associated vertex and edge loops.

Enums

Public

Name Remarks
EDuplicateTriBehavior In ReinsertSubmesh, a problem can arise where the mesh we are inserting has duplicate triangles of the base mesh.

Variables

Public

Name Type Remarks Include Path Unreal Specifiers
Mesh FDynamicMesh3 * The mesh we will be editing DynamicMeshEditor.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

bool AddTriangleFan_OrderedVertexLoop ( int CenterVertex,
const TArray< int >& VertexLoop,
int GroupID,
FDynamicMeshEditResult& ResultOut
)

 Fill hole with a triangle fan given an existing (unconnected) center vertex and an ordered loop of boundary vertices on the hole border. DynamicMeshEditor.h  

void AppendColors ( const FDynamicMesh3* AppendMesh,
const FDynamicMeshColorOverlay* FromOverlay,
FDynamicMeshColorOverlay* ToOverlay,
const FIndexMapi& VertexMap,
const FIndexMapi& TriangleMap,
FIndexMapi& ColorMapOut
)

 Append Colors from one attribute overlay to another. DynamicMeshEditor.h  

void AppendElementSubset ( const FDynamicMesh3* FromMesh,
const TSet< int >& TriangleROI,
const TSet< int >& VertexROI,
const TDynamicMeshOverlay< RealType, ElementSize >* FromOverlay,
TDynamicMeshOverlay< RealType, ElementSize >* ToOverlay
)

 Append overlay elements in both ROIs from one overlay to another DynamicMeshEditor.h  

void AppendMesh ( const TTriangleMeshAdapter< double >* AppendMesh,
FMeshIndexMappings& IndexMapsOut,
TFunction< FVector3d(int, const FVector3d&)> PositionTransform
)

 Append input mesh to our internal Mesh. DynamicMeshEditor.h  

void AppendMesh ( const FDynamicMesh3* AppendMesh,
FMeshIndexMappings& IndexMapsOut,
TFunction< FVector3d(int, const FVector3d&)> PositionTransform,
TFunction< FVector3d(int, const FVector3d&)> NormalTransform,
bool bReverseOrientation
)

 Append input mesh to our internal mesh DynamicMeshEditor.h  

void AppendNormals ( const FDynamicMesh3* AppendMesh,
const FDynamicMeshNormalOverlay* FromNormals,
FDynamicMeshNormalOverlay* ToNormals,
const FIndexMapi& VertexMap,
const FIndexMapi& TriangleMap,
TFunction< FVector3d(int, const FVector3d&)> NormalTransform,
FIndexMapi& NormalMapOut
)

 Append normals from one attribute overlay to another. DynamicMeshEditor.h  

void AppendTriangles ( const FDynamicMesh3* SourceMesh,
const TArrayView< const int >& SourceTriangles,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult& ResultOut,
bool bComputeTriangleMap
)

 Append triangles of an existing mesh. DynamicMeshEditor.h  

void AppendUVs ( const FDynamicMesh3* AppendMesh,
const FDynamicMeshUVOverlay* FromUVs,
FDynamicMeshUVOverlay* ToUVs,
const FIndexMapi& VertexMap,
const FIndexMapi& TriangleMap,
FIndexMapi& UVMapOut
)

 Append UVs from one attribute overlay to another. DynamicMeshEditor.h  

FVector3f ComputeAndSetQuadNormal ( const FIndex2i& QuadTris,
bool bIsPlanar
)

 Calculate and set the per-triangle normals of the two input quads. DynamicMeshEditor.h  

void CopyAttributes ( int FromTriangleID,
int ToTriangleID,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult& ResultOut
)

 Copy all attribute-layer values from one triangle to another, using the IndexMaps to track and re-use shared attribute values. DynamicMeshEditor.h  

void DisconnectTriangles ( const TArray< int >& Triangles,
bool bPreventBowties
)

 Disconnects triangles (without constructing boundary loops) such that the input Triangles are not connected to any other triangles in the mesh DynamicMeshEditor.h  

bool DisconnectTriangles ( const TSet< int >& TriangleSet,
const TArray< FEdgeLoop >& BoundaryLoops,
TArray< FLoopPairSet >& LoopSetOut,
bool bAllowBoundaryVertices
)

 Variant of DisconnectTriangles that takes a precomputed set of BoundaryLoops of the triangles, and a TSet of Triangles. DynamicMeshEditor.h  

bool DisconnectTriangles ( const TArray< int >& Triangles,
TArray< FLoopPairSet >& LoopSetOut,
bool bHandleBoundaryVertices
)

 Finds boundary loops of connected components of a set of triangles, and duplicates the vertices along the boundary, such that the triangles become disconnected. DynamicMeshEditor.h  

bool DisconnectTrianglesAlongEdges ( const TSet< int32 >& Edges,
TArray< int32 >* AddedVertexIDs
)

 Disconnect triangles along the given Edges, so that all input edges become boundary edges. DynamicMeshEditor.h  

void DuplicateTriangles ( const TArray< int >& Triangles,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult& ResultOut
)

 Duplicate triangles of a mesh. DynamicMeshEditor.h  

int FindOrCreateDuplicateColor ( int ElementID,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult* ResultOut
)

 Find "new" color for input color element under Index mapping, or create new if missing DynamicMeshEditor.h  

int FindOrCreateDuplicateGroup ( int TriangleID,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult& ResultOut
)

 Find "new" group for input group under Index mapping, or create new if missing DynamicMeshEditor.h  

int FindOrCreateDuplicateNormal ( int ElementID,
int NormalLayerIndex,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult* ResultOut
)

 Find "new" normal for input normal element under Index mapping, or create new if missing DynamicMeshEditor.h  

int FindOrCreateDuplicateUV ( int ElementID,
int UVLayerIndex,
FMeshIndexMappings& IndexMaps
)

 Find "new" UV for input UV element under Index mapping, or create new if missing DynamicMeshEditor.h  

int FindOrCreateDuplicateVertex ( int VertexID,
FMeshIndexMappings& IndexMaps,
FDynamicMeshEditResult& ResultOut
)

 Mesh element copying / duplication DynamicMeshEditor.h  

void InvertTriangleNormals ( const TArray< int >& Triangles
)

 Flip the normals of the given triangles. DynamicMeshEditor.h  

bool ReinsertSubmesh ( const FDynamicSubmesh3& Submesh,
FOptionallySparseIndexMap& SubToNewV,
TArray< int >* NewTris,
EDuplicateTriBehavior DuplicateBehavior
)

 Update a Base Mesh from a Submesh; See FMeshRegionOperator::BackPropropagate for a usage example. DynamicMeshEditor.h  

bool RemoveIsolatedVertices()

 Remove any vertices that are not used by any triangles DynamicMeshEditor.h  

int RemoveSmallComponents ( double MinVolume,
double MinArea,
int MinTriangleCount
)

 Remove any connected components with volume or area below the given thresholds DynamicMeshEditor.h  

bool RemoveTriangles ( const TArray< int >& Triangles,
bool bRemoveIsolatedVerts,
TFunctionRef< void(int)> OnRemoveTriFunc
)

 Remove a list of triangles from the mesh, and optionally any vertices that are now orphaned DynamicMeshEditor.h  

bool RemoveTriangles ( const TArray< int >& Triangles,
bool bRemoveIsolatedVerts
)

 Remove a list of triangles from the mesh, and optionally any vertices that are now orphaned DynamicMeshEditor.h  

void RescaleAttributeUVs ( float UVScale,
bool bWorldSpace,
int UVLayerIndex,
TOptional< FTransformSRT3d > ToWorld
)

 Rescale UVs for the whole mesh, for the given UV attribute layer DynamicMeshEditor.h  

void ReverseTriangleOrientations ( const TArray< int >& Triangles,
bool bInvertNormals
)

 Normal utility functions. DynamicMeshEditor.h  

void SetGeneralTubeUVs ( const TArray< int >& Triangles,
const TArray< int >& VertexIDs1,
const TArray< int >& MatchedIndices1,
const TArray< int >& VertexIDs2,
const TArray< int >& MatchedIndices2,
const TArray< float >& UValues,
const FVector3f& VDir,
float UVScaleFactor,
const FVector2f& UVTranslation,
int UVLayerIndex
)

 For triangles connecting loops of corresponded vertices, set UVs in a cylindrical pattern so that the U coordinate starts at 0 for the first corresponded pair of vertices, and cycles around to 1 Assumes Triangles array stores indices of triangles in progressively filling the tube, starting with VertexIDs*[0]. DynamicMeshEditor.h  

void SetQuadNormals ( const FIndex2i& QuadTris,
const FVector3f& Normal
)

 Create and set new shared per-triangle normals for a pair of triangles that share one edge (ie a quad) DynamicMeshEditor.h  

void SetQuadUVsFromProjection ( const FIndex2i& QuadTris,
const FFrame3d& ProjectionFrame,
float UVScaleFactor,
const FVector2f& UVTranslation,
int UVLayerIndex
)

 UV utility functions. DynamicMeshEditor.h  

void SetTriangleNormals ( const TArray< int >& Triangles
)

 Create and set new shared per-triangle normals for a list of triangles. DynamicMeshEditor.h  

void SetTriangleNormals ( const TArray< int >& Triangles,
const FVector3f& Normal
)

 Create and set new shared per-triangle normals for a list of triangles DynamicMeshEditor.h  

void SetTriangleUVsFromProjection ( const TArray< int32 >& Triangles,
const FFrame3d& ProjectionFrame,
float UVScaleFactor,
const FVector2f& UVTranslation,
bool bShiftToOrigin,
int32 UVLayerIndex
)

 Project triangles onto a plane defined by the ProjectionFrame and use that to create/set new shared per-triangle UVs. DynamicMeshEditor.h  

void SetTriangleUVsFromProjection ( const TArray< int >& Triangles,
const FFrame3d& ProjectionFrame,
const FVector2f& UVScale,
const FVector2f& UVTranslation,
int UVLayerIndex,
bool bShiftToOrigin,
bool bNormalizeBeforeScaling
)

 Project triangles onto a plane defined by the ProjectionFrame and use that to create/set new shared per-triangle UVs. DynamicMeshEditor.h  

void SetTubeNormals ( const TArray< int >& Triangles,
const TArray< int >& VertexIDs1,
const TArray< int >& MatchedIndices1,
const TArray< int >& VertexIDs2,
const TArray< int >& MatchedIndices2,
bool bReverseNormals
)

 For a 'tube' of triangles connecting loops of corresponded vertices, set smooth normals such that corresponding vertices have corresponding normals DynamicMeshEditor.h  

void SplitBowties ( int VertexID,
TArray< int32 >* NewVertices
)

 Splits any bowties specifically on the given vertex, and (if not null) updates (does not reset!) NewVertices with any added vertices DynamicMeshEditor.h  

void SplitBowties ( FDynamicMeshEditResult& ResultOut
)

 Splits all bowties across the whole mesh DynamicMeshEditor.h  

void SplitBowties ( int VertexID,
FDynamicMeshEditResult& ResultOut
)

 Splits any bowties specifically on the given vertex, and updates (does not reset!) ResultOut with any added vertices DynamicMeshEditor.h  

void SplitBowtiesAtTriangles ( const TArray< int32 >& TriangleIDs,
FDynamicMeshEditResult& ResultOut
)

 Splits bowties attached to any of the given triangles, and updates (does not reset!) ResultOut with any added vertices DynamicMeshEditor.h  

bool StitchSparselyCorrespondedVertexLoops ( const TArray< int >& VertexIDs1,
const TArray< int >& MatchedIndices1,
const TArray< int >& VertexIDs2,
const TArray< int >& MatchedIndices2,
FDynamicMeshEditResult& ResultOut,
bool bReverseOrientation
)

 Stitch together two loops of vertices where vertices are only sparsely corresponded DynamicMeshEditor.h  

bool StitchVertexLoopsMinimal ( const TArray< int >& VertexLoop1,
const TArray< int >& VertexLoop2,
FDynamicMeshEditResult& ResultOut
)

 Create and Remove Triangle Functions. DynamicMeshEditor.h  

bool StitchVertexLoopToTriVidPairSequence ( const TArray< TPair< int32, TPair< int8, int8 > > >& TriVidPairs1,
const TArray< int >& VertexLoop2,
FDynamicMeshEditResult& ResultOut
)

 Given a sequence of edges in the form given by ConvertLoopToTriVidPairSequence and a loop of vertices, stitch the two together. DynamicMeshEditor.h  

bool WeldVertexLoops ( const TArray< int32 >& VertexLoop1,
const TArray< int32 >& VertexLoop2
)

 Weld together two loops of vertices. Loops must be oriented (ordered) correctly for your use case. DynamicMeshEditor.h  

Static

Name Remarks Include Path Unreal Specifiers

static bool ConvertLoopToTriVidPairSequence ( const FDynamicMesh3& Mesh,
const TArray< int32 >& VidLoop,
const TArray< int32 >& EdgeLoop,
TArray< TPair< int32, TPair< int8, int8 > > >& TriVertPairsOut
)

 Converts a loop to a sequence of edge identifiers that are both Vid and Eid independent. DynamicMeshEditor.h  

static bool CreateSeamsAtEdges ( const TSet< int32 >& EidsToMakeIntoSeams,
TDynamicMeshOverlay< float, 3 >* Overlay,
TArray< int32 >* AddedElementIDs
)

 Cut existing 3D attribute overlay topology with a set of edges. DynamicMeshEditor.h  

static bool CreateSeamsAtEdges ( const TSet< int32 >& EidsToMakeIntoSeams,
TDynamicMeshOverlay< float, 2 >* Overlay,
TArray< int32 >* AddedElementIDs
)

 Cut existing 2D attribute overlay topology with a set of edges. DynamicMeshEditor.h  

static bool RemoveSeamsAtEdges ( const TSet< int32 >& EidsToRemoveAsSeams,
TDynamicMeshOverlay< float, 3 >* Overlay
)

 Merge any seams in the given (3D attribute) Overlay along the given mesh edge IDs DynamicMeshEditor.h  

static bool RemoveSeamsAtEdges ( const TSet< int32 >& EidsToRemoveAsSeams,
TDynamicMeshOverlay< float, 2 >* Overlay
)

 Merge any seams in the given 2D attribute Overlay along the given mesh edge IDs DynamicMeshEditor.h  

static bool SplitMesh ( const FDynamicMesh3* SourceMesh,
TArray< FDynamicMesh3 >& SplitMeshes,
TFunctionRef< int(int)> TriIDToMeshID,
int DeleteMeshID,
TArray< int32 >* MeshIDPerSplitMesh,
bool bSortByMeshID
)

 Create multiple meshes out of the source mesh by splitting triangles out. DynamicMeshEditor.h  

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