vtkReebGraph Class Reference

#include <vtkReebGraph.h>

Inheritance diagram for vtkReebGraph:

Inheritance graph
[legend]
Collaboration diagram for vtkReebGraph:

Collaboration graph
[legend]

List of all members.


Detailed Description

Reeb graph computation for PL scalar fields.

vtkReebGraph is a class that computes a Reeb graph given a PL scalar field (vtkDataArray) defined on a simplicial mesh. A Reeb graph is a concise representation of the connectivity evolution of the level sets of a scalar function.

It is particularly useful in visualization (optimal seed set computation, fast flexible isosurface extraction, automated transfer function design, feature-driven visualization, etc.) and computer graphics (shape deformation, shape matching, shape compression, etc.).

Reference: "Sur les points singuliers d'une forme de Pfaff completement integrable ou d'une fonction numerique", G. Reeb, Comptes-rendus de l'Academie des Sciences, 222:847-849, 1946.

vtkReebGraph implements one of the latest and most robust Reeb graph computation algorithms.

Reference: "Robust on-line computation of Reeb graphs: simplicity and speed", V. Pascucci, G. Scorzelli, P.-T. Bremer, and A. Mascarenhas, ACM Transactions on Graphics, Proc. of SIGGRAPH 2007.

vtkReebGraph provides methods for computing multi-resolution topological hierarchies through topological simplification. Topoligical simplification can be either driven by persistence homology concepts (default behavior) or by application specific metrics (see vtkReebGraphSimplificationMetric). In the latter case, designing customized simplification metric evaluation algorithms enables the user to control the definition of what should be considered as noise or signal in the topological filtering process.

References: "Topological persistence and simplification", H. Edelsbrunner, D. Letscher, and A. Zomorodian, Discrete Computational Geometry, 28:511-533, 2002.

"Extreme elevation on a 2-manifold", P.K. Agarwal, H. Edelsbrunner, J. Harer, and Y. Wang, ACM Symposium on Computational Geometry, pp. 357-365, 2004.

"Simplifying flexible isosurfaces using local geometric measures", H. Carr, J. Snoeyink, M van de Panne, IEEE Visualization, 497-504, 2004

"Loop surgery for volumetric meshes: Reeb graphs reduced to contour trees", J. Tierny, A. Gyulassy, E. Simon, V. Pascucci, IEEE Trans. on Vis. and Comp. Graph. (Proc of IEEE VIS), 15:1177-1184, 2009.

Reeb graphs can be computed from 2D data (vtkPolyData, with triangles only) or 3D data (vtkUnstructuredGrid, with tetrahedra only), sequentially (see the "Build" calls) or in streaming (see the "StreamTriangle" and "StreamTetrahedron" calls).

vtkReebGraph inherits from vtkMutableDirectedGraph.

Each vertex of a vtkReebGraph object represents a critical point of the scalar field where the connectivity of the related level set changes (creation, deletion, split or merge of connected components). A vtkIdTypeArray (called "Vertex Ids") is associated with the VertexData of a vtkReebGraph object, in order to retrieve if necessary the exact Ids of the corresponding vertices in the input mesh.

The edges of a vtkReebGraph object represent the regions of the input mesh separated by the critical contours of the field, and where the connectivity of the input field does not change. A vtkVariantArray is associated with the EdgeDta of a vtkReebGraph object and each entry of this array is a vtkAbstractArray containing the Ids of the vertices of those regions, sorted by function value (useful for flexible isosurface extraction or level set signature computation, for instance).

See Graphics/Testing/Cxx/TestReebGraph.cxx for examples of traversals and typical usages (customized simplification, skeletonization, contour spectra, etc.) of a vtkReebGraph object.

See also:
vtkReebGraphSimplificationMetric vtkPolyDataToReebGraphFilter vtkUnstructuredGridToReebGraphFilter vtkReebGraphSimplificationFilter vtkReebGraphSurfaceSkeletonFilter vtkReebGraphVolumeSkeletonFilter vtkAreaContourSpectrumFilter vtkVolumeContourSpectrumFilter
Tests:
Graphics/Testing/Cxx/TestReebGraph.cxx

Definition at line 129 of file vtkReebGraph.h.


Public Types

enum  { ERR_INCORRECT_FIELD = -1, ERR_NO_SUCH_FIELD = -2, ERR_NOT_A_SIMPLICIAL_MESH = -3 }
typedef vtkMutableDirectedGraph Superclass

Public Member Functions

virtual const char * GetClassName ()
virtual int IsA (const char *type)
void PrintSelf (ostream &os, vtkIndent indent)
void PrintNodeData (ostream &os, vtkIndent indent)
int Build (vtkPolyData *mesh, vtkDataArray *scalarField)
int Build (vtkUnstructuredGrid *mesh, vtkDataArray *scalarField)
int Build (vtkPolyData *mesh, vtkIdType scalarFieldId)
int Build (vtkUnstructuredGrid *mesh, vtkIdType scalarFieldId)
int Build (vtkPolyData *mesh, const char *scalarFieldName)
int Build (vtkUnstructuredGrid *mesh, const char *scalarFieldName)
void CloseStream ()
void DeepCopy (vtkDataObject *src)
void Set (vtkMutableDirectedGraph *g)
int StreamTriangle (vtkIdType vertex0Id, double scalar0, vtkIdType vertex1Id, double scalar1, vtkIdType vertex2Id, double scalar2)
int StreamTetrahedron (vtkIdType vertex0Id, double scalar0, vtkIdType vertex1Id, double scalar1, vtkIdType vertex2Id, double scalar2, vtkIdType vertex3Id, double scalar3)
int Simplify (double simplificationThreshold, vtkReebGraphSimplificationMetric *simplificationMetric)

Static Public Member Functions

static vtkReebGraphNew ()
static int IsTypeOf (const char *type)
static vtkReebGraphSafeDownCast (vtkObject *o)

Protected Member Functions

 vtkReebGraph ()
 ~vtkReebGraph ()

Protected Attributes

Implementation * Storage

Member Typedef Documentation

Reimplemented from vtkMutableDirectedGraph.

Definition at line 136 of file vtkReebGraph.h.


Member Enumeration Documentation

anonymous enum

Enumerator:
ERR_INCORRECT_FIELD 
ERR_NO_SUCH_FIELD 
ERR_NOT_A_SIMPLICIAL_MESH 

Definition at line 140 of file vtkReebGraph.h.


Constructor & Destructor Documentation

vtkReebGraph::vtkReebGraph (  )  [protected]

vtkReebGraph::~vtkReebGraph (  )  [protected]


Member Function Documentation

static vtkReebGraph* vtkReebGraph::New (  )  [static]

Create an object with Debug turned off, modified time initialized to zero, and reference counting on.

Reimplemented from vtkMutableDirectedGraph.

virtual const char* vtkReebGraph::GetClassName (  )  [virtual]

Reimplemented from vtkMutableDirectedGraph.

static int vtkReebGraph::IsTypeOf ( const char *  name  )  [static]

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkMutableDirectedGraph.

virtual int vtkReebGraph::IsA ( const char *  name  )  [virtual]

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkMutableDirectedGraph.

static vtkReebGraph* vtkReebGraph::SafeDownCast ( vtkObject o  )  [static]

Reimplemented from vtkMutableDirectedGraph.

void vtkReebGraph::PrintSelf ( ostream &  os,
vtkIndent  indent 
) [virtual]

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkMutableDirectedGraph.

void vtkReebGraph::PrintNodeData ( ostream &  os,
vtkIndent  indent 
)

int vtkReebGraph::Build ( vtkPolyData mesh,
vtkDataArray scalarField 
)

Build the Reeb graph of the field 'scalarField' defined on the surface mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' has vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh (for example, the surface mesh contains quads instead of triangles).

int vtkReebGraph::Build ( vtkUnstructuredGrid mesh,
vtkDataArray scalarField 
)

Build the Reeb graph of the field 'scalarField' defined on the volume mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' has vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh.

int vtkReebGraph::Build ( vtkPolyData mesh,
vtkIdType  scalarFieldId 
)

Build the Reeb graph of the field given by the Id 'scalarFieldId', defined on the surface mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' as vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh (for example, the surface mesh contains quads instead of triangles). vtkReebGraph::ERR_NO_SUCH_FIELD: the scalar field given by the Id 'scalarFieldId' does not exist.

int vtkReebGraph::Build ( vtkUnstructuredGrid mesh,
vtkIdType  scalarFieldId 
)

Build the Reeb graph of the field given by the Id 'scalarFieldId', defined on the volume mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' as vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh. vtkReebGraph::ERR_NO_SUCH_FIELD: the scalar field given by the Id 'scalarFieldId' does not exist.

int vtkReebGraph::Build ( vtkPolyData mesh,
const char *  scalarFieldName 
)

Build the Reeb graph of the field given by the name 'scalarFieldName', defined on the surface mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' as vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh (for example, the surface mesh contains quads instead of triangles). vtkReebGraph::ERR_NO_SUCH_FIELD: the scalar field given by the name 'scalarFieldName' does not exist.

int vtkReebGraph::Build ( vtkUnstructuredGrid mesh,
const char *  scalarFieldName 
)

Build the Reeb graph of the field given by the name 'scalarFieldName', defined on the volume mesh 'mesh'. Returned values: vtkReebGraph::ERR_INCORRECT_FIELD: 'scalarField' does not have as many tuples as 'mesh' as vertices. vtkReebGraph::ERR_NOT_A_SIMPLICIAL_MESH: the input mesh 'mesh' is not a simplicial mesh. vtkReebGraph::ERR_NO_SUCH_FIELD: the scalar field given by the name 'scalarFieldName' does not exist.

int vtkReebGraph::StreamTriangle ( vtkIdType  vertex0Id,
double  scalar0,
vtkIdType  vertex1Id,
double  scalar1,
vtkIdType  vertex2Id,
double  scalar2 
)

Streaming Reeb graph computation. Add to the streaming computation the triangle of the vtkPolyData surface mesh described by vertex0Id, scalar0 vertex1Id, scalar1 vertex2Id, scalar2 where vertexId is the Id of the vertex in the vtkPolyData structure and scalar is the corresponding scalar field value. IMPORTANT: The stream _must_ be finalized with the "CloseStream" call.

int vtkReebGraph::StreamTetrahedron ( vtkIdType  vertex0Id,
double  scalar0,
vtkIdType  vertex1Id,
double  scalar1,
vtkIdType  vertex2Id,
double  scalar2,
vtkIdType  vertex3Id,
double  scalar3 
)

Streaming Reeb graph computation. Add to the streaming computation the tetrahedra of the vtkUnstructuredGrid volume mesh described by vertex0Id, scalar0 vertex1Id, scalar1 vertex2Id, scalar2 vertex3Id, scalar3 where vertexId is the Id of the vertex in the vtkUnstructuredGrid structure and scalar is the corresponding scalar field value. IMPORTANT: The stream _must_ be finalized with the "CloseStream" call.

void vtkReebGraph::CloseStream (  ) 

Finalize internal data structures, in the case of streaming computations (with StreamTriangle or StreamTetrahedron). After this call, no more triangle or tetrahedron can be inserted via StreamTriangle or StreamTetrahedron. IMPORTANT: This method _must_ be called when the input stream is finished. If you need to get a snapshot of the Reeb graph during the streaming process (to parse or simplify it), do a DeepCopy followed by a CloseStream on the copy.

void vtkReebGraph::DeepCopy ( vtkDataObject obj  )  [virtual]

Deep copies the data object into this graph. If it is an incompatible graph, reports an error.

Reimplemented from vtkGraph.

int vtkReebGraph::Simplify ( double  simplificationThreshold,
vtkReebGraphSimplificationMetric simplificationMetric 
)

Simplify the Reeb graph given a threshold 'simplificationThreshold' (between 0 and 1). This method is the core feature for Reeb graph multi-resolution hierarchy construction. Return the number of arcs that have been removed through the simplification process. 'simplificationThreshold' represents a "scale", under which each Reeb graph feature is considered as noise. 'simplificationThreshold' is expressed as a fraction of the scalar field overall span. It can vary from 0 (no simplification) to 1 (maximal simplification). 'simplificationMetric' is an object in charge of evaluating the importance of a Reeb graph arc at each step of the simplification process. if 'simplificationMetric' is NULL, the default strategy (persitence of the scalar field) is used. Customized simplification metric evaluation algorithm can be designed (see vtkReebGraphSimplificationMetric), enabling the user to control the definition of what should be considered as noise or signal. References: "Topological persistence and simplification", H. Edelsbrunner, D. Letscher, and A. Zomorodian, Discrete Computational Geometry, 28:511-533, 2002. "Extreme elevation on a 2-manifold", P.K. Agarwal, H. Edelsbrunner, J. Harer, and Y. Wang, ACM Symposium on Computational Geometry, pp. 357-365, 2004. "Simplifying flexible isosurfaces using local geometric measures", H. Carr, J. Snoeyink, M van de Panne, IEEE Visualization, 497-504, 2004 "Loop surgery for volumetric meshes: Reeb graphs reduced to contour trees", J. Tierny, A. Gyulassy, E. Simon, V. Pascucci, IEEE Trans. on Vis. and Comp. Graph. (Proc of IEEE VIS), 15:1177-1184,2009.

void vtkReebGraph::Set ( vtkMutableDirectedGraph g  ) 

Use a pre-defined Reeb graph (post-processing). Use with caution!


Member Data Documentation

Implementation* vtkReebGraph::Storage [protected]

Definition at line 280 of file vtkReebGraph.h.


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

Generated on Wed Aug 24 12:02:33 2011 for VTK by  doxygen 1.5.6