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TopologyLevel Class Reference

An interface for accessing data in a specific level of a refined topology hierarchy. More...

#include <topologyLevel.h>

Public Member Functions

Methods to inspect the overall inventory of components:

All three main component types are indexed locally within each level. For some topological relationships – notably face-vertices, which is often the only relationship of interest – the total number of entries is also made available.

int GetNumVertices () const
 Return the number of vertices in this level.
 
int GetNumFaces () const
 Return the number of faces in this level.
 
int GetNumEdges () const
 Return the number of edges in this level.
 
int GetNumFaceVertices () const
 Return the total number of face-vertices, i.e. the sum of all vertices for all faces.
 
Methods to inspect topological relationships for individual components:

With three main component types (vertices, faces and edges), for each of the three components the TopologyLevel stores the incident/adjacent components of the other two types. So there are six relationships available for immediate inspection. All are accessed by methods that return an array of fixed size containing the indices of the incident components.

For some of the relations, i.e. those for which the incident components are of higher order or 'contain' the component itself (e.g. a vertex has incident faces that contain it), an additional 'local index' is available that identifies the component within each of its neighbors. For example, if vertex V is the k'th vertex in some face F, then when F occurs in the set of incident vertices of V, the local index corresponding to F will be k. The ordering of local indices matches the ordering of the incident component to which it corresponds.

ConstIndexArray GetFaceVertices (Index f) const
 Access the vertices incident a given face.
 
ConstIndexArray GetFaceEdges (Index f) const
 Access the edges incident a given face.
 
ConstIndexArray GetEdgeVertices (Index e) const
 Access the vertices incident a given edge.
 
ConstIndexArray GetEdgeFaces (Index e) const
 Access the faces incident a given edge.
 
ConstIndexArray GetVertexFaces (Index v) const
 Access the faces incident a given vertex.
 
ConstIndexArray GetVertexEdges (Index v) const
 Access the edges incident a given vertex.
 
ConstLocalIndexArray GetVertexFaceLocalIndices (Index v) const
 Access the local indices of a vertex with respect to its incident faces.
 
ConstLocalIndexArray GetVertexEdgeLocalIndices (Index v) const
 Access the local indices of a vertex with respect to its incident edges.
 
ConstLocalIndexArray GetEdgeFaceLocalIndices (Index e) const
 Access the local indices of an edge with respect to its incident faces.
 
Index FindEdge (Index v0, Index v1) const
 Identify the edge matching the given vertex pair.
 
Methods to inspect other topological properties of individual components:
bool IsEdgeNonManifold (Index e) const
 Return if the edge is non-manifold.
 
bool IsVertexNonManifold (Index v) const
 Return if the vertex is non-manifold.
 
bool IsEdgeBoundary (Index e) const
 Return if the edge is a boundary (only one incident face)
 
bool IsVertexBoundary (Index v) const
 Return if the vertex is on a boundary (at least one incident boundary edge)
 
bool IsVertexCorner (Index v) const
 Return if the vertex is a corner (only one incident face)
 
bool IsVertexValenceRegular (Index v) const
 Return if the valence of the vertex is regular (must be manifold)
 
Methods to inspect feature tags for individual components:

While only a subset of components may have been tagged with features such as sharpness, all such features have a default value and so all components can be inspected.

float GetEdgeSharpness (Index e) const
 Return the sharpness assigned a given edge.
 
float GetVertexSharpness (Index v) const
 Return the sharpness assigned a given vertex.
 
bool IsEdgeInfSharp (Index e) const
 Return if the edge is infinitely-sharp.
 
bool IsVertexInfSharp (Index v) const
 Return if the vertex is infinitely-sharp.
 
bool IsEdgeSemiSharp (Index e) const
 Return if the edge is semi-sharp.
 
bool IsVertexSemiSharp (Index v) const
 Return if the vertex is semi-sharp.
 
bool IsFaceHole (Index f) const
 Return if a given face has been tagged as a hole.
 
Sdc::Crease::Rule GetVertexRule (Index v) const
 Return the subdivision rule assigned a given vertex specific to this level.
 
Methods to inspect face-varying data:

Face-varying data is organized into topologically independent channels, each with an integer identifier. Access to face-varying data generally requires the specification of a channel, though with a single channel being a common situation the first/only channel will be assumed if unspecified.

A face-varying channel is composed of a set of values that may be shared by faces meeting at a common vertex. Just as there are sets of vertices that are associated with faces by index (ranging from 0 to num-vertices - 1), face-varying values are also referenced by index (ranging from 0 to num-values -1).

The face-varying values associated with a face are accessed similarly to the way in which vertices associated with the face are accessed – an array of fixed size containing the indices for each corner is provided for inspection, iteration, etc.

When the face-varying topology around a vertex "matches", it has the same limit properties and so results in the same limit surface when collections of adjacent vertices match. Like other references to "topology", this includes consideration of sharpness. So it may be that face-varying values are assigned around a vertex on a boundary in a way that appears to match, but the face-varying interpolation option requires sharpening of that vertex in face-varying space – the difference in the topology of the resulting limit surfaces leading to the query returning false for the match. The edge case is simpler in that it only considers continuity across the edge, not the entire neighborhood around each end vertex.

int GetNumFVarChannels () const
 Return the number of face-varying channels (should be same for all levels)
 
int GetNumFVarValues (int channel=0) const
 Return the total number of face-varying values in a particular channel (the upper bound of a face-varying value index)
 
ConstIndexArray GetFaceFVarValues (Index f, int channel=0) const
 Access the face-varying values associated with a particular face.
 
bool DoesVertexFVarTopologyMatch (Index v, int channel=0) const
 Return if face-varying topology around a vertex matches.
 
bool DoesEdgeFVarTopologyMatch (Index e, int channel=0) const
 Return if face-varying topology across the edge only matches.
 
bool DoesFaceFVarTopologyMatch (Index f, int channel=0) const
 Return if face-varying topology around a face matches.
 
Methods to identify parent or child components in adjoining levels of refinement:
ConstIndexArray GetFaceChildFaces (Index f) const
 Access the child faces (in the next level) of a given face.
 
ConstIndexArray GetFaceChildEdges (Index f) const
 Access the child edges (in the next level) of a given face.
 
ConstIndexArray GetEdgeChildEdges (Index e) const
 Access the child edges (in the next level) of a given edge.
 
Index GetFaceChildVertex (Index f) const
 Return the child vertex (in the next level) of a given face.
 
Index GetEdgeChildVertex (Index e) const
 Return the child vertex (in the next level) of a given edge.
 
Index GetVertexChildVertex (Index v) const
 Return the child vertex (in the next level) of a given vertex.
 
Index GetFaceParentFace (Index f) const
 Return the parent face (in the previous level) of a given face.
 

Debugging aides:

class TopologyRefiner
 
bool ValidateTopology () const
 
void PrintTopology (bool children=true) const
 
 TopologyLevel ()
 
 ~TopologyLevel ()
 

Detailed Description

An interface for accessing data in a specific level of a refined topology hierarchy.

TopologyLevel provides an interface to data in a specific level of a topology hierarchy. Instances of TopologyLevel are created and owned by a TopologyRefiner, which will return const-references to them. Such references are only valid during the lifetime of the TopologyRefiner that created and returned them, and only for a given refinement, i.e. if the TopologyRefiner is re-refined, any references to TopoologyLevels are invalidated.

Definition at line 49 of file topologyLevel.h.

Constructor & Destructor Documentation

◆ TopologyLevel()

TopologyLevel ( )
inline

Definition at line 300 of file topologyLevel.h.

◆ ~TopologyLevel()

~TopologyLevel ( )
inline

Definition at line 301 of file topologyLevel.h.

Member Function Documentation

◆ DoesEdgeFVarTopologyMatch()

bool DoesEdgeFVarTopologyMatch ( Index  e,
int  channel = 0 
) const
inline

Return if face-varying topology across the edge only matches.

Definition at line 247 of file topologyLevel.h.

◆ DoesFaceFVarTopologyMatch()

bool DoesFaceFVarTopologyMatch ( Index  f,
int  channel = 0 
) const
inline

Return if face-varying topology around a face matches.

Definition at line 252 of file topologyLevel.h.

◆ DoesVertexFVarTopologyMatch()

bool DoesVertexFVarTopologyMatch ( Index  v,
int  channel = 0 
) const
inline

Return if face-varying topology around a vertex matches.

Definition at line 242 of file topologyLevel.h.

◆ FindEdge()

Index FindEdge ( Index  v0,
Index  v1 
) const
inline

Identify the edge matching the given vertex pair.

Definition at line 120 of file topologyLevel.h.

◆ GetEdgeChildEdges()

ConstIndexArray GetEdgeChildEdges ( Index  e) const
inline

Access the child edges (in the next level) of a given edge.

Definition at line 268 of file topologyLevel.h.

◆ GetEdgeChildVertex()

Index GetEdgeChildVertex ( Index  e) const
inline

Return the child vertex (in the next level) of a given edge.

Definition at line 274 of file topologyLevel.h.

◆ GetEdgeFaceLocalIndices()

ConstLocalIndexArray GetEdgeFaceLocalIndices ( Index  e) const
inline

Access the local indices of an edge with respect to its incident faces.

Definition at line 117 of file topologyLevel.h.

◆ GetEdgeFaces()

ConstIndexArray GetEdgeFaces ( Index  e) const
inline

Access the faces incident a given edge.

Definition at line 102 of file topologyLevel.h.

◆ GetEdgeSharpness()

float GetEdgeSharpness ( Index  e) const
inline

Return the sharpness assigned a given edge.

Definition at line 173 of file topologyLevel.h.

◆ GetEdgeVertices()

ConstIndexArray GetEdgeVertices ( Index  e) const
inline

Access the vertices incident a given edge.

Definition at line 99 of file topologyLevel.h.

◆ GetFaceChildEdges()

ConstIndexArray GetFaceChildEdges ( Index  f) const
inline

Access the child edges (in the next level) of a given face.

Definition at line 265 of file topologyLevel.h.

◆ GetFaceChildFaces()

ConstIndexArray GetFaceChildFaces ( Index  f) const
inline

Access the child faces (in the next level) of a given face.

Definition at line 262 of file topologyLevel.h.

◆ GetFaceChildVertex()

Index GetFaceChildVertex ( Index  f) const
inline

Return the child vertex (in the next level) of a given face.

Definition at line 271 of file topologyLevel.h.

◆ GetFaceEdges()

ConstIndexArray GetFaceEdges ( Index  f) const
inline

Access the edges incident a given face.

Definition at line 96 of file topologyLevel.h.

◆ GetFaceFVarValues()

ConstIndexArray GetFaceFVarValues ( Index  f,
int  channel = 0 
) const
inline

Access the face-varying values associated with a particular face.

Definition at line 237 of file topologyLevel.h.

◆ GetFaceParentFace()

Index GetFaceParentFace ( Index  f) const
inline

Return the parent face (in the previous level) of a given face.

Definition at line 280 of file topologyLevel.h.

◆ GetFaceVertices()

ConstIndexArray GetFaceVertices ( Index  f) const
inline

Access the vertices incident a given face.

Definition at line 93 of file topologyLevel.h.

◆ GetNumEdges()

int GetNumEdges ( ) const
inline

Return the number of edges in this level.

Definition at line 68 of file topologyLevel.h.

◆ GetNumFaces()

int GetNumFaces ( ) const
inline

Return the number of faces in this level.

Definition at line 65 of file topologyLevel.h.

◆ GetNumFaceVertices()

int GetNumFaceVertices ( ) const
inline

Return the total number of face-vertices, i.e. the sum of all vertices for all faces.

Definition at line 71 of file topologyLevel.h.

◆ GetNumFVarChannels()

int GetNumFVarChannels ( ) const
inline

Return the number of face-varying channels (should be same for all levels)

Definition at line 230 of file topologyLevel.h.

◆ GetNumFVarValues()

int GetNumFVarValues ( int  channel = 0) const
inline

Return the total number of face-varying values in a particular channel (the upper bound of a face-varying value index)

Definition at line 234 of file topologyLevel.h.

◆ GetNumVertices()

int GetNumVertices ( ) const
inline

Return the number of vertices in this level.

Definition at line 62 of file topologyLevel.h.

◆ GetVertexChildVertex()

Index GetVertexChildVertex ( Index  v) const
inline

Return the child vertex (in the next level) of a given vertex.

Definition at line 277 of file topologyLevel.h.

◆ GetVertexEdgeLocalIndices()

ConstLocalIndexArray GetVertexEdgeLocalIndices ( Index  v) const
inline

Access the local indices of a vertex with respect to its incident edges.

Definition at line 114 of file topologyLevel.h.

◆ GetVertexEdges()

ConstIndexArray GetVertexEdges ( Index  v) const
inline

Access the edges incident a given vertex.

Definition at line 108 of file topologyLevel.h.

◆ GetVertexFaceLocalIndices()

ConstLocalIndexArray GetVertexFaceLocalIndices ( Index  v) const
inline

Access the local indices of a vertex with respect to its incident faces.

Definition at line 111 of file topologyLevel.h.

◆ GetVertexFaces()

ConstIndexArray GetVertexFaces ( Index  v) const
inline

Access the faces incident a given vertex.

Definition at line 105 of file topologyLevel.h.

◆ GetVertexRule()

Sdc::Crease::Rule GetVertexRule ( Index  v) const
inline

Return the subdivision rule assigned a given vertex specific to this level.

Definition at line 194 of file topologyLevel.h.

◆ GetVertexSharpness()

float GetVertexSharpness ( Index  v) const
inline

Return the sharpness assigned a given vertex.

Definition at line 176 of file topologyLevel.h.

◆ IsEdgeBoundary()

bool IsEdgeBoundary ( Index  e) const
inline

Return if the edge is a boundary (only one incident face)

Definition at line 134 of file topologyLevel.h.

◆ IsEdgeInfSharp()

bool IsEdgeInfSharp ( Index  e) const
inline

Return if the edge is infinitely-sharp.

Definition at line 179 of file topologyLevel.h.

◆ IsEdgeNonManifold()

bool IsEdgeNonManifold ( Index  e) const
inline

Return if the edge is non-manifold.

Definition at line 128 of file topologyLevel.h.

◆ IsEdgeSemiSharp()

bool IsEdgeSemiSharp ( Index  e) const
inline

Return if the edge is semi-sharp.

Definition at line 185 of file topologyLevel.h.

◆ IsFaceHole()

bool IsFaceHole ( Index  f) const
inline

Return if a given face has been tagged as a hole.

Definition at line 191 of file topologyLevel.h.

◆ IsVertexBoundary()

bool IsVertexBoundary ( Index  v) const
inline

Return if the vertex is on a boundary (at least one incident boundary edge)

Definition at line 137 of file topologyLevel.h.

◆ IsVertexCorner()

bool IsVertexCorner ( Index  v) const
inline

Return if the vertex is a corner (only one incident face)

Definition at line 140 of file topologyLevel.h.

◆ IsVertexInfSharp()

bool IsVertexInfSharp ( Index  v) const
inline

Return if the vertex is infinitely-sharp.

Definition at line 182 of file topologyLevel.h.

◆ IsVertexNonManifold()

bool IsVertexNonManifold ( Index  v) const
inline

Return if the vertex is non-manifold.

Definition at line 131 of file topologyLevel.h.

◆ IsVertexSemiSharp()

bool IsVertexSemiSharp ( Index  v) const
inline

Return if the vertex is semi-sharp.

Definition at line 188 of file topologyLevel.h.

◆ IsVertexValenceRegular()

bool IsVertexValenceRegular ( Index  v) const
inline

Return if the valence of the vertex is regular (must be manifold)

Note that this test only determines if the valence of the vertex is regular with respect to the assigned subdivision scheme – not if the neighborhood around the vertex is regular. The latter depends on a number of factors including the incident faces of the vertex (they must all be regular) and the presence of sharpness at the vertex itself or its incident edges.

The regularity of the valence is a necessary but not a sufficient condition in determining the regularity of the neighborhood. For example, while the valence of an interior vertex may be regular, its neighborhood is not if the vertex was made infinitely sharp. Conversely, a corner vertex is considered regular by its valence but its neighborhood is not if the vertex was not made infinitely sharp.

Whether the valence of the vertex is regular is also a property that remains the same for the vertex in all subdivision levels. In contrast, the regularity of the region around the vertex may change as the presence of irregular faces or semi-sharp features is reduced by subdivision.

Definition at line 162 of file topologyLevel.h.

◆ PrintTopology()

void PrintTopology ( bool  children = true) const
inline

Definition at line 287 of file topologyLevel.h.

◆ ValidateTopology()

bool ValidateTopology ( ) const
inline

Definition at line 286 of file topologyLevel.h.

Friends And Related Function Documentation

◆ TopologyRefiner

friend class TopologyRefiner
friend

Definition at line 292 of file topologyLevel.h.


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