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FDynamicMesh3

[FDynamicMesh3](API\Runtime\GeometryCore\DynamicMesh\FDynamicMesh3) is a dynamic triangle mesh class.

API > API/Runtime > API/Runtime/GeometryCore > API/Runtime/GeometryCore/DynamicMesh

References

   
Module GeometryCore
Header /Engine/Source/Runtime/GeometryCore/Public/DynamicMesh/DynamicMesh3.h
Include #include "DynamicMesh/DynamicMesh3.h"

Syntax

class FDynamicMesh3

Remarks

FDynamicMesh3 is a dynamic triangle mesh class. The mesh has has connectivity, is an indexed mesh, and allows for gaps in the index space.

internally, all data is stored in POD-type buffers, except for the vertex->edge links, which are stored as List's. The arrays of POD data are stored in TDynamicVector's, so they grow in chunks, which is relatively efficient. The actual blocks are arrays, so they can be efficiently mem-copied into larger buffers if necessary.

Reference counts for verts/tris/edges are stored as separate FRefCountVector instances.

Vertices are stored as doubles, although this should be easily changed if necessary, as the internal data structure is not exposed

Per-vertex Vertex Normals, Colors, and UVs are optional and stored as floats. Note that in practice, these are generally only used as scratch space, in limited circumstances, usually when needed for performance reasons. Most of our geometry code instead prefers to read attributes from the per-triangle AttributeSet accessed via Attributes() (see TDynamicMeshOverlay for a description of the structure). For instance, an empty (but existing) attribute set will take precedence over non-empty vertex normals in much of our processing code.

For each vertex, VertexEdgeLists[i] is the unordered list of connected edges. The elements of the list are indices into the edges list. This list is unsorted but can be traversed in-order (ie cw/ccw) at some additional cost.

Triangles are stored as 3 ints, with optionally a per-triangle integer group id. The group IDs stored here DO get widely used and preserved in our geometry code (unlike the per-vertex attributes described earlier), even though the AttributeSet can store group IDs as well (potentially in multiple layers).

The edges of a triangle are similarly stored as 3 ints, in triangle_edes. If the triangle is [v1,v2,v3], then the triangle edges [e1,e2,e3] are e1=edge(v1,v2), e2=edge(v2,v3), e3=edge(v3,v1), where the e# are indexes into edges.

Edges are stored as tuples of 4 ints. If the edge is between v1 and v2, with neighbour tris t1 and t2, then the edge is [min(v1,v2), max(v1,v2), t1, t2]. For a boundary edge, t2 is InvalidID. t1 is never InvalidID.

Most of the class assumes that the mesh is manifold. Many functions will work if the topology is non-manifold, but behavior of operators like Split/Flip/Collapse edge is untested.

The function CheckValidity() does extensive sanity checking on the mesh data structure. Use this to test your code, both for mesh construction and editing!!

Variables

  Type Name Description
Protected variable TUniquePtr< FDynamicMeshAttributeSet > AttributeSet Extended Attributes for the Mesh (UV layers, Hard Normals, additional Polygroup Layers, etc)
Protected variable bool bEnableShapeChangeStamp Enable/Disable updating of ShapeChangeStamp.
Protected variable FRefCountVector EdgeRefCounts Reference counts of edge indices.
Protected variable TDynamicVector< FEdge > Edges List of edge elements.
Protected variable int GroupIDCounter Upper bound on the triangle group IDs used in the mesh (may be larger than the actual maximum if triangles have been deleted)
Protected variable std::atomic< uint32 > ShapeChangeStamp If bEnableShapeChangeStamp=true, The shape change stamp is incremented any time a function that modifies the mesh shape or topology is called
Protected variable std::atomic< uint32 > TopologyChangeStamp The topology change stamp is incremented any time a function that modifies the mesh topology is called
Protected variable TDynamicVector< FIndex3i > TriangleEdges List of triangle edge triplets [Edge0 Edge1 Edge2]
Protected variable TOptional< TDynamicVector< int > > TriangleGroups (optional) List of per-triangle group identifiers
Protected variable FRefCountVector TriangleRefCounts Reference counts of triangle indices.
Protected variable TDynamicVector< FIndex3i > Triangles List of triangle vertex-index triplets [Vert0 Vert1 Vert2]
Protected variable TOptional< TDynamicVector< FVector3f > > VertexColors (optional) List of per-vertex colors
Protected variable FSmallListSet VertexEdgeLists List of per-vertex edge one-rings
Protected variable TOptional< TDynamicVector< FVector3f > > VertexNormals (optional) List of per-vertex normals
Protected variable FRefCountVector VertexRefCounts Reference counts of vertex indices.
Protected variable TOptional< TDynamicVector< FVector2f > > VertexUVs (optional) List of per-vertex uv's
Protected variable TDynamicVector< FVector3d > Vertices List of vertex positions

Constructors

  Type Name Description
Public function   Default constructor
Public function  

FDynamicMesh3 ( const FDynamicMesh3& CopyMesh
)

 Copy/Move construction
Public function  

FDynamicMesh3 ( FDynamicMesh3&& MoveMesh
)

  
Public function    
Public function  

FDynamicMesh3 ( const FMeshShapeGenerator* Generator
)

 Construction from Mesh Generator
Public function  

FDynamicMesh3 ( bool bWantNormals,
bool bWantColors,
bool bWantUVs,
bool bWantTriGroups
)

 Construct an empty mesh with specified attributes

Destructors

  Type Name Description
Public function Virtual   Destructor

Functions

  Type Name Description
Protected function int

AddEdgeInternal ( int vA,
int vB,
int tA,
int tB
)

  
Protected function void

AddTriangleEdge ( int TriangleID,
int v0,
int v1,
int j,
int EdgeID
)

  
Protected function int

AddTriangleInternal ( int a,
int b,
int c,
int e0,
int e1,
int e2
)

  
Protected function void

AllocateEdgesList ( int VertexID
)

  
Public function int  
Public function int

AppendTriangle ( int Vertex0,
int Vertex1,
int Vertex2,
int GroupID
)

 Vertex0, Vertex1, and Vertex2 must be distinct and refer to existing, valid vertices
Public function int

AppendTriangle ( const FIndex3i& TriVertices,
int GroupID
)

 TriVertices must be distinct and refer to existing, valid vertices
Public function int

AppendVertex ( const FVector3d& Position
)

 Append vertex at position, returns vid
Public function int

AppendVertex ( const FVertexInfo& VertInfo
)

 Mesh Construction Append vertex at position and other fields, returns vid
Public function int

AppendVertex ( const FDynamicMesh3& SourceMesh,
int SourceVertexID
)

 Copy vertex SourceVertexID from existing SourceMesh, returns new vertex id
Public function FDynamicMeshAttributeSet *  
Public function Const const FDynamicMeshAttributeSet *  
Public function Virtual void Call this before a set of unsafe InsertTriangle() calls
Public function Virtual void Support for inserting vertex and triangle at specific IDs.
Public function Const FRefCountVector::FilteredEnumerable  
Public function Const double

CalculateWindingNumber ( const FVector3d& QueryPoint
)

 Compute mesh winding number, from Jacobson et.
Public function Virtual Const EMeshResult

CanCollapseEdge ( int vKeep,
int vRemove,
double EdgeParameterT
)

 Tests whether collapsing the specified edge using the CollapseEdge function would succeed.
Public function Virtual Const EMeshResult

CanCollapseEdge ( int vKeep,
int vRemove,
const FCollapseEdgeOptions& Options
)

  
Protected function Virtual Const EMeshResult

CanCollapseEdgeInternal ( int vKeep,
int vRemove,
double collapse_t,
FEdgeCollapseInfo* OutCollapseInfo
)

 We keep this version of CanCollapseEdge internal because the CollapseInfo struct may only be partially filled out by the function
Public function Virtual Const bool

CheckValidity ( FValidityOptions ValidityOptions,
EValidityCheckFailMode FailMode
)

 Checks that the mesh is well-formed, ie all internal data structures are consistent
Public function void

Clear ()

 Discard all data
Public function Virtual EMeshResult

CollapseEdge ( int KeepVertID,
int RemoveVertID,
double EdgeParameterT,
FEdgeCollapseInfo& CollapseInfo
)

 Collapse the edge between the two vertices, if topologically possible.
Public function Virtual EMeshResult

CollapseEdge ( int KeepVertID,
int RemoveVertID,
const FCollapseEdgeOptions& Options,
FEdgeCollapseInfo& CollapseInfo
)

 Collapse the edge between the two vertices, if topologically possible.
Public function Virtual EMeshResult

CollapseEdge ( int KeepVertID,
int RemoveVertID,
FEdgeCollapseInfo& CollapseInfo
)

 Collapse the edge between the two vertices, if topologically possible.
Public function Virtual EMeshResult

CollapseEdge ( int KeepVertID,
int RemoveVertID,
double EdgeParameterT,
const FCollapseEdgeOptions& Options,
FEdgeCollapseInfo& CollapseInfo
)

 Collapse the edge between the two vertices, if topologically possible.
Public function void

CompactCopy ( const FDynamicMesh3& CopyMesh,
bool bNormals,
bool bColors,
bool bUVs,
bool bAttributes,
FCompactMaps* CompactInfo
)

 Copy input mesh while compacting, i.e. removing unused vertices/triangles/edges.
Public function void

CompactInPlace ( FCompactMaps* CompactInfo
)

 Mesh Edit operations Compact mesh in-place, by moving vertices around and rewriting indices.
Public function Const double Returns measure of compactness in range [0,1], where 1 is fully compacted
Public function bool

Copy ( const FMeshShapeGenerator* Generator
)

 Initialize mesh from the output of a MeshShapeGenerator (assumes Generate() was already called)
Public function void

Copy ( const FDynamicMesh3& CopyMesh,
bool bNormals,
bool bColors,
bool bUVs,
bool bAttributes
)

 Set internal data structures to be a copy of input mesh using the specified attributes
Public function void  
Public function void  
Public function void  
Public function void  
Public function void  
Public function Const int  
Protected function Const bool

EdgeHasTriangle ( int EdgeID,
int TriangleID
)

  
Protected function Const bool

EdgeHasVertex ( int EdgeID,
int VertexID
)

  
Public function Const edge_iterator  
Public function Const value_iteration< FEdge > Enumerate edges.
Public function void  
Public function void

EnableMatchingAttributes ( const FDynamicMesh3& ToMatch,
bool bClearExisting,
bool bDiscardExtraAttributes
)

 Ensure that all the same extended attributes available in ToMatch are also enabled.
Public function void

EnableMeshComponents ( int MeshComponentsFlags
)

 Vertex and Triangle attribute arrays Enable requested set of mesh components (triangle groups and vertex normals/colors/UVs) and discard any that are not requested
Public function void

EnableTriangleGroups ( int InitialGroupID
)

  
Public function void

EnableVertexColors ( const FVector3f& InitialColor
)

  
Public function void

EnableVertexNormals ( const FVector3f& InitialNormal
)

  
Public function void

EnableVertexUVs ( const FVector2f& InitialUV
)

  
Public function Virtual void Call after a set of unsafe InsertTriangle() calls to rebuild free list
Public function Virtual void Call after a set of unsafe InsertVertex() calls to rebuild free list
Public function Const void

EnumerateEdgeTriangles ( int32 EdgeID,
TFunctionRef< void(int32)> ApplyFunc
)

 Call ApplyFunc for each triangle connected to an Edge (1 or 2 triangles)
Public function Const void

EnumerateTriEdgeIDsFromEdgeID ( const int32 EdgeID,
const TFunctionRef< void(FMeshTriEdgeID TriEdgeID)>& TriEdgeFunc
)

 Applies a given function to both TriEdgeIDs which a given EdgeID is associated with
Public function Const void

EnumerateTriEdgeIDsFromTriID ( const int TriID,
const TFunctionRef< void(FMeshTriEdgeID TriEdgeID)>& TriEdgeFunc
)

 Applies a given function to both TriEdgeIDs which each EdgeID in a given Triangle is associated with
Public function Const void

EnumerateVertexEdges ( int32 VertexID,
TFunctionRef< void(int32)> EdgeFunc
)

 Call EdgeFunc for each one-ring edge of a vertex.
Public function Const void

EnumerateVertexTriangles ( int32 VertexID,
TFunctionRef< void(int32)> ApplyFunc
)

 Call ApplyFunc for each one-ring triangle of a vertex.
Public function Const void

EnumerateVertexVertices ( int32 VertexID,
TFunctionRef< void(int32)> VertexFunc
)

 Call VertexFunc for each one-ring vertex neighbour of a vertex.
Public function Const int

FindEdge ( int VertexA,
int VertexB
)

 Find id of edge connecting A and B
Public function Const int

FindEdgeFromTri ( int VertexA,
int VertexB,
int TriangleID
)

 Find edgeid for edge [a,b] from triangle that contains the edge.
Public function Const int

FindEdgeFromTriPair ( int TriangleA,
int TriangleB
)

 Find edgeid for edge connecting two triangles
Protected function Const int32

FindEdgeInternal ( int32 vA,
int32 vB,
bool& bIsBoundary
)

  
Public function Const int

FindTriangle ( int A,
int B,
int C
)

 Find triangle made up of any permutation of vertices [a,b,c]
Protected function Const int

FindTriangleEdge ( int TriangleID,
int vA,
int vB
)

 Returns edge ID
Public function Virtual EMeshResult

FlipEdge ( int EdgeVertA,
int EdgeVertB,
FEdgeFlipInfo& FlipInfo
)

 Calls FlipEdge() on the edge between two vertices, if it exists
Public function Virtual EMeshResult

FlipEdge ( int EdgeAB,
FEdgeFlipInfo& FlipInfo
)

 Flip/Rotate an edge of the mesh.
Public function Const bool

GetAllVertexGroups ( int VertexID,
TArray< int >& GroupsOut
)

 Returns all group IDs at vertex
Public function Const int

GetAllVtxBoundaryEdges ( int VertexID,
TArray< int >& EdgeListOut
)

 Find edge ids of boundary edges connected to vertex.
Public function Const FAxisAlignedBox3d

GetBounds ( bool bParallel
)

 Geometric queries Returns bounding box of all mesh vertices (including unreferenced vertices)
Public function Const uint64 ChangeStamp is a combination of the Shape and Topology ChangeStamps
Public function Const const TDynamicVector< FVector3f > *  
Public function Const int  
Public function Const FEdge

GetEdge ( int EdgeID
)

 Get the vertices and triangles of an edge, returned as [v0,v1,t0,t1], where t1 may be InvalidID
Public function Const FVector3d

GetEdgeNormal ( int EdgeID
)

 Returns average normal of connected face normals
Public function Const FIndex2i

GetEdgeOpposingV ( int EdgeID
)

 If edge has vertices [a,b], and is connected two triangles [a,b,c] and [a,b,d], this returns [c,d], or [c,InvalidID] for a boundary edge
Public function Const FVector3d

GetEdgePoint ( int EdgeID,
double ParameterT
)

 Get point along edge, t clamped to range [0,1]
Public function Const const FEdge &

GetEdgeRef ( int EdgeID
)

 Get the vertices and triangles of an edge, returned as [v0,v1,t0,t1], where t1 may be InvalidID
Public function Const const TDynamicVector< FEdge > &  
Public function Const const FRefCountVector &  
Public function Const FIndex2i

GetEdgeT ( int EdgeID
)

 Get the triangle pair for an edge. The second triangle may be InvalidID
Public function Const FIndex2i

GetEdgeV ( int EdgeID
)

 Get the vertex pair for an edge
Public function Const bool

GetEdgeV ( int EdgeID,
FVector3d& a,
FVector3d& b
)

 Get the vertex positions of an edge
Public function Const int  
Public function Const const TDynamicVector< FVector3f > *  
Protected function Const FIndex2i

GetOrderedOneRingEdgeTris ( int VertexID,
int EdgeID
)

 Utility function that returns one or two triangles of edge, used to enumerate vertex one-ring triangles The logic is a bit tricky to follow without drawing it out on paper, but this will only return each triangle once, for the 'outgoing' edge from the vertex, and each triangle only has one such edge at any vertex (including boundary triangles)
Public function Const FIndex2i

GetOrientedBoundaryEdgeV ( int EdgeID
)

 Return edge vertex indices, but oriented based on attached triangle (rather than min-sorted)
Protected function Const int

GetOtherEdgeTriangle ( int EdgeID,
int TriangleID
)

  
Protected function Const int

GetOtherEdgeVertex ( int EdgeID,
int VertexID
)

  
Public function Const uint32 ShapeChangeStamp is incremented any time a mesh vertex position is changed or the mesh topology is modified, if bEnableShapeChangeStamp=true
Public function Const uint32 TopologyChangeStamp is incremented when the mesh topology is modified
Public function Const FIndex3i

GetTriangle ( int TriangleID
)

 Get triangle vertices
Public function Const const TDynamicVector< FIndex3i > &  
Public function Const int

GetTriangleGroup ( int tID
)

  
Public function Const const TDynamicVector< int > *  
Public function Const const FIndex3i &

GetTriangleRef ( int TriangleID
)

 Get triangle vertices
Public function Const const TDynamicVector< FIndex3i > &  
Public function Const const FRefCountVector &  
Public function Const double

GetTriArea ( int TriangleID
)

 Calculate area triangle
Public function Const FVector3d

GetTriBaryNormal ( int TriangleID,
double Bary0,
double Bary1,
double Bary2
)

 Interpolate vertex normals of triangle using barycentric coordinates
Public function Const FVector3d

GetTriBaryPoint ( int TriangleID,
double Bary0,
double Bary1,
double Bary2
)

 Interpolate vertex positions of triangle using barycentric coordinates
Public function Const void

GetTriBaryPoint ( int TriangleID,
double Bary0,
double Bary1,
double Bary2,
FVertexInfo& VertInfo
)

 Compute interpolated vertex attributes at point of triangle
Public function Const FAxisAlignedBox3d

GetTriBounds ( int TriangleID
)

 Construct bounding box of triangle as efficiently as possible
Public function Const FVector3d

GetTriCentroid ( int TriangleID
)

 Compute centroid of triangle
Public function Const int

GetTriEdge ( int TriangleID,
int j
)

 Get one of the edges of a triangle
Public function Const FMeshTriEdgeID

GetTriEdgeIDFromEdgeID ( int EdgeID
)

 Return (triangle, edge_index) representation for given Edge ID
Public function Const FIndex3i

GetTriEdges ( int TriangleID
)

 Get triangle edges
Public function Const const FIndex3i &

GetTriEdgesRef ( int TriangleID
)

 Get triangle edges
Public function Const FFrame3d

GetTriFrame ( int TriangleID,
int Edge
)

 Construct stable frame at triangle centroid, where frame.Z is face normal, and frame.X is aligned with edge nEdge of triangle.
Public function Const void

GetTriInfo ( int TriangleID,
FVector3d& Normal,
double& Area,
FVector3d& Centroid
)

 Compute triangle normal, area, and centroid all at once.
Public function Const double

GetTriInternalAngleR ( int TriangleID,
int i
)

 Compute internal angle at vertex i of triangle (where i is 0,1,2);
Public function Const FVector3d

GetTriInternalAnglesR ( int TriangleID
)

 Compute internal angles at all vertices of triangle
Public function Const FIndex3i

GetTriNeighbourTris ( int TriangleID
)

 Find the neighbour triangles of a triangle (any of them might be InvalidID)
Public function Const FVector3d

GetTriNormal ( int TriangleID
)

 Calculate face normal of triangle
Public function Const double

GetTriSolidAngle ( int TriangleID,
const FVector3d& p
)

 Compute solid angle of oriented triangle tID relative to point p - see WindingNumber()
Public function Const FVector3d

GetTriVertex ( int TriangleID,
int j
)

 Get the position of one of the vertices of a triangle
Public function Const void

GetTriVertices ( int TriangleID,
VecType& v0,
VecType& v1,
VecType& v2
)

 Get the three vertex positions of a triangle
Public function Const const TDynamicVector< FVector2f > *  
Public function Const FVector3d

GetVertex ( int VertexID
)

 Vertex/Tri/Edge accessors
Public function Const bool

GetVertex ( int VertexID,
FVertexInfo& VertInfo,
bool bWantNormals,
bool bWantColors,
bool bWantUVs
)

 Get extended vertex information
Public function Const FVector3f

GetVertexColor ( int vID
)

  
Public function Const const FSmallListSet &  
Protected function Const void

GetVertexEdgesList ( int VertexID,
TArray< int >& EdgesOut
)

  
Public function Const FFrame3d

GetVertexFrame ( int VertexID,
bool bFrameNormalY,
FVector3d* UseNormal
)

 Compute a normal/tangent frame at vertex that is "stable" as long as the mesh topology doesn't change, meaning that one axis of the frame will be computed from projection of outgoing edge.
Public function Const bool

GetVertexGroups ( int VertexID,
FIndex4i& GroupsOut
)

 Returns up to 4 group IDs at vertex. Returns false if > 4 encountered
Public function Const FVertexInfo

GetVertexInfo ( int VertexID
)

 Get all vertex information available
Public function Const FVector3f

GetVertexNormal ( int vID
)

  
Public function Const const FVector3d &

GetVertexRef ( int VertexID
)

  
Public function Const FVector2f

GetVertexUV ( int vID
)

  
Public function Const const TDynamicVector< FVector3d > & Direct buffer access
Public function Const const FRefCountVector &  
Public function Const int

GetVtxBoundaryEdges ( int VertexID,
int& Edge0Out,
int& Edge1Out
)

 Returns count of boundary edges at vertex, and the first two boundary edges if found.
Public function Const EMeshResult

GetVtxContiguousTriangles ( int VertexID,
TArray< int >& TrianglesOut,
TArray< int >& ContiguousGroupLengths,
TArray< bool >& GroupIsLoop
)

 Get triangles connected to vertex in contiguous order, with multiple groups if vertex is a bowtie.
Public function Const int

GetVtxEdgeCount ( int VertexID
)

  
Public function Const void

GetVtxNbrhood ( int EdgeID,
int VertexID,
int& OtherVertOut,
int& OppVert1Out,
int& OppVert2Out,
int& Tri1Out,
int& Tri2Out
)

 Given an edge and vertex on that edge, returns other vertex of edge, the two opposing verts, and the two connected triangles (OppVert2Out and Tri2Out are be InvalidID for boundary edge)
Public function Const void

GetVtxOneRingCentroid ( int VertexID,
FVector3d& CentroidOut
)

 Fastest possible one-ring centroid.
Public function Const int

GetVtxSingleTriangle ( int VertexID
)

  
Public function Const int

GetVtxTriangleCount ( int VertexID
)

 Return # of triangles attached to vID, or -1 if invalid vertex
Public function Const EMeshResult

GetVtxTriangles ( int VertexID,
TArray< int >& TrianglesOut
)

 Get triangle one-ring at vertex.
Public function Const bool  
Public function Const bool  
Public function Const bool  
Public function Const bool  
Public function Const bool  
Public function Const bool  
Public function Const bool  
Public function EMeshResult

InsertTriangle ( int TriangleID,
const FIndex3i& TriVertices,
int GroupID,
bool bUnsafe
)

 Insert triangle at given index, assuming it is unused.
Public function EMeshResult

InsertVertex ( int VertexID,
const FVertexInfo& VertInfo,
bool bUnsafe
)

 Insert vertex at given index, assuming it is unused.
Public function Const bool

IsBoundaryEdge ( int EdgeID
)

 Topological queries Returns true if edge is on the mesh boundary, ie only connected to one triangle
Public function Const bool

IsBoundaryTriangle ( int TriangleID
)

 Returns true if any edge of triangle is a boundary edge
Public function Const bool

IsBoundaryVertex ( int VertexID
)

 Returns true if the vertex is part of any boundary edges
Public function Const bool

IsBowtieVertex ( int VertexID
)

 Returns true if vID is a "bowtie" vertex, ie multiple disjoint triangle sets in one-ring
Public function Const bool  
Public function Const bool Returns true if vertices, edges, and triangles are all dense (Count == MaxID)
Public function Const bool  
Public function Const bool  
Public function Const bool

IsEdge ( int EdgeID
)

  
Public function Const bool

IsGroupBoundaryEdge ( int EdgeID
)

 Returns true if the two triangles connected to edge have different group IDs
Public function Const bool

IsGroupBoundaryVertex ( int VertexID
)

 Returns true if vertex has more than one tri group in its tri nbrhood
Public function Const bool

IsGroupJunctionVertex ( int VertexID
)

 Returns true if more than two group boundary edges meet at vertex (ie 3+ groups meet at this vertex)
Public function Const bool

IsReferencedVertex ( int VertexID
)

  
Public function Virtual Const bool

IsSameAs ( const FDynamicMesh3& OtherMesh,
const FSameAsOptions& Options
)

 Check if another mesh is the same as this mesh.
Public function Virtual Const bool

IsSameAs ( const FDynamicMesh3& OtherMesh,
const FSameAsOptions& Options,
FMeshDifferenceInfo& OutMeshDifferenceInfo
)

 Check if another mesh is the same as this mesh.
Public function Const bool

IsTriangle ( int TriangleID
)

  
Public function Const bool

IsVertex ( int VertexID
)

  
Public function Const int  
Public function Const int  
Public function Const int  
Public function Const int  
Public function Virtual EMeshResult

MergeEdges ( int KeepEdgeID,
int DiscardEdgeID,
FMergeEdgesInfo& MergeInfo,
bool bCheckValidOrientation
)

 Weld one edge to the other.
Public function Virtual EMeshResult

MergeEdges ( int KeepEdgeID,
int DiscardEdgeID,
double InterpolationT,
FMergeEdgesInfo& MergeInfo,
bool bCheckValidOrientation
)

 Given two edges of the mesh, weld both their vertices, so that one edge is removed.
Public function Virtual EMeshResult

MergeVertices ( int KeepVid,
int DiscardVid,
FMergeVerticesInfo& MergeInfo
)

 Weld DiscardVid to KeepVid.
Public function Virtual EMeshResult

MergeVertices ( int KeepVid,
int DiscardVid,
double InterpolationT,
FMergeVerticesInfo& MergeInfo
)

 Weld DiscardVid to KeepVid. Equivalent to calling the options overload with default options.
Public function Virtual EMeshResult

MergeVertices ( int KeepVid,
int DiscardVid,
double InterpolationT,
const FMergeVerticesOptions& Options,
FMergeVerticesInfo& MergeInfo
)

 Weld DiscardVid to KeepVid, if topologically possible and options allow.
Public function Virtual Const FString Debug utility functions Returns a debug string that contains mesh statistics and other information
Public function Virtual EMeshResult

PokeTriangle ( int TriangleID,
FPokeTriangleInfo& PokeInfo
)

 Call PokeTriangle at the centroid of the triangle
Public function Virtual EMeshResult

PokeTriangle ( int TriangleID,
const FVector3d& BaryCoordinates,
FPokeTriangleInfo& PokeInfo
)

 Insert a new vertex inside a triangle, ie do a 1 to 3 triangle split
Public function EMeshResult

RemoveTriangle ( int TriangleID,
bool bRemoveIsolatedVertices,
bool bPreserveManifold
)

 Remove a triangle from the mesh.
Public function void Remove unused vertices. Note: Does not compact the remaining vertices.
Public function EMeshResult

RemoveVertex ( int VertexID,
bool bPreserveManifold
)

 Remove vertex VertexID and all connected triangles.
Protected function int

ReplaceEdgeTriangle ( int EdgeID,
int tOld,
int tNew
)

  
Protected function int

ReplaceEdgeVertex ( int EdgeID,
int vOld,
int vNew
)

  
Protected function int

ReplaceTriangleEdge ( int EdgeID,
int eOld,
int eNew
)

  
Protected function int

ReplaceTriangleVertex ( int TriangleID,
int vOld,
int vNew
)

  
Public function void

ReverseOrientation ( bool bFlipNormals
)

 Reverse the ccw/cw orientation of all triangles in the mesh, and optionally flip the vertex normals if they exist
Public function EMeshResult

ReverseTriOrientation ( int TriangleID
)

 Reverse the ccw/cw orientation of a triangle
Protected function void

ReverseTriOrientationInternal ( int TriangleID
)

  
Public function void Serialize the mesh to an archive.
Protected function void

SerializeInternal ( FArchive& Ar,
void*
)

  
Protected function void  
Protected function void

SerializeInternal ( FArchive& Ar,
void* Ptr
)

 Internal implementations for serialization to allow for better code separation between different versions and other implementation details.
Protected function void

SetEdgeTrianglesInternal ( int EdgeID,
int t0,
int t1
)

  
Protected function void

SetEdgeVerticesInternal ( int EdgeID,
int a,
int b
)

  
Public function void

SetShapeChangeStampEnabled ( bool bEnabled
)

 Change Tracking support
Public function Virtual EMeshResult

SetTriangle ( int TriangleID,
const FIndex3i& NewVertices,
bool bRemoveIsolatedVertices
)

 Rewrite the triangle to reference the new tuple of vertices.
Protected function void

SetTriangleEdgesInternal ( int TriangleID,
int e0,
int e1,
int e2
)

  
Public function void

SetTriangleGroup ( int tid,
int group_id
)

  
Protected function void

SetTriangleInternal ( int TriangleID,
int v0,
int v1,
int v2
)

 Internal functions
Public function void

SetVertex ( int VertexID,
const FVector3d& vNewPos,
bool bTrackChange
)

 Set vertex position
Public function void

SetVertexColor ( int vID,
const FVector3f& vNewColor
)

  
Public function void

SetVertexNormal ( int vID,
const FVector3f& vNewNormal
)

  
Public function void

SetVertexUV ( int vID,
const FVector2f& vNewUV
)

  
Public function EMeshResult

SplitEdge ( int EdgeVertA,
int EdgeVertB,
FEdgeSplitInfo& SplitInfo
)

 Splits the edge between two vertices at the midpoint, if this edge exists
Public function Virtual EMeshResult

SplitEdge ( int EdgeAB,
FEdgeSplitInfo& SplitInfo,
double SplitParameterT
)

 Split an edge of the mesh by inserting a vertex.
Public function Virtual EMeshResult

SplitVertex ( int VertexID,
const TArrayView< const int >& TrianglesToUpdate,
FVertexSplitInfo& SplitInfo
)

 Clones the given vertex and updates any provided triangles to use the new vertex if/where they used the old one.
Public function Virtual bool

SplitVertexWouldLeaveIsolated ( int VertexID,
const TArrayView< const int >& TrianglesToUpdate
)

 Tests whether splitting the given vertex with the given triangles would leave no triangles attached to the original vertex (creating an isolated vertex)
Public function Const int  
Protected function Const bool

TriangleHasVertex ( int TriangleID,
int VertexID
)

  
Public function Const triangle_iterator  
Public function Const value_iteration< FIndex3i > Enumerate all triangles in the mesh
Protected function Const bool

TriHasNeighbourTri ( int CheckTriID,
int NbrTriID
)

  
Protected function Const bool

TriHasSequentialVertices ( int TriangleID,
int vA,
int vB
)

  
Public function void

UpdateChangeStamps ( bool bShapeChange,
bool bTopologyChange
)

 Increment the specified ChangeStamps, if they are enabled. Thread-safe.
Public function Const int  
Public function Const vertex_iterator  
Public function Const value_iteration< FVector3d > Enumerate positions of all vertices in mesh
Public function Const FSmallListSet::ValueEnumerable

VtxEdgesItr ( int VertexID
)

  
Public function Const vtx_triangles_enumerable

VtxTrianglesItr ( int VertexID
)

  
Public function Const FSmallListSet::MappedValueEnumerable

VtxVerticesItr ( int VertexID
)

  

Operators

  Type Name Description
Public function const FDynamicMesh3 &

operator= ( const FDynamicMesh3& CopyMesh
)

 Copy and move assignment
Public function const FDynamicMesh3 &

operator= ( FDynamicMesh3&& MoveMesh
)

  

Classes

  Type Name Description
Public struct FCollapseEdgeOptions    
Public struct FEdge    
Public struct FMergeVerticesOptions    
Public struct FMeshDifferenceInfo    
Public struct FSameAsOptions Options for the IsSameAs check  
Public struct FValidityOptions Options for what the validity check will permit  

Typedefs

Name Description
edge_iterator  
FEdgeCollapseInfo  
FEdgeFlipInfo TODO:
FEdgeSplitInfo  
FMergeEdgesInfo  
FMergeVerticesInfo  
FPokeTriangleInfo  
FVertexSplitInfo  
triangle_iterator  
value_iteration  
vertex_iterator Simplify names for iterations
vtx_triangles_enumerable  

Constants

Name Description
DuplicateTriangleID DuplicateTriangleID is returned by AppendTriangle() to indicate that the added triangle already exists in the mesh, and was ignored because we do not support duplicate triangles
InvalidEdge  
InvalidID InvalidID indicates that a vertex/edge/triangle ID is invalid
InvalidTriangle  
InvalidVertex  
NonManifoldID NonManifoldID is returned by AppendTriangle() to indicate that the added triangle would result in nonmanifold geometry and hence was ignored

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