NAME
vtkVectorTopology - mark points where the vector field vanishes (singularities exist).
SYNOPSIS
#include "/opt/vtk-c++/graphics/vtkVectorTopology.h"
class VTK_EXPORT vtkVectorTopology : public vtkDataSetToPolyDataFilter
vtkVectorTopology();
static vtkVectorTopology *New() {return new vtkVectorTopology;};
const char *GetClassName() {return "vtkVectorTopology";};
void PrintSelf(ostream& os, vtkIndent indent);
void SetDistance(float);
float GetDistance();
DESCRIPTION
vtkVectorTopology is a filter that marks points where the vector field vanishes. At these points various important flow features are found, including regions of circulation, separation, etc. The region around these areas are good places to start streamlines. (The vector field vanishes in cells where the x-y-z vector components each pass through zero.)
The output of this filter is a set of vertices. These vertices mark the vector field singularities. You can use an object like vtkGlyph3D to place markers at these points, or use the vertices to initiate streamlines.
The Distance instance variable controls the accuracy of placement of the vertices. Smaller values result in greater execution times.
The input to this filter is any dataset type. The position of the vertices is found by sampling the cell in parametric space. Sampling is repeated until the Distance criterion is satisfied.
SEE ALSO
vtkGlyph3D vtkStreamLine
SUMMARY
void SetDistance(float)
Specify distance from singularity to generate point.
vtkVectorTopology()
Construct object with distance 0.1.