vtkPolyDataConnectivityFilter

Section: Visualization Toolkit Graphics Classes

Usage

vtkPolyDataConnectivityFilter is a filter that extracts cells that share common points and/or satisfy a scalar threshold criterion. (Such a group of cells is called a region.) The filter works in one of six ways: 1) extract the largest connected region in the dataset; 2) extract specified region numbers; 3) extract all regions sharing specified point ids; 4) extract all regions sharing specified cell ids; 5) extract the region closest to the specified point; or 6) extract all regions (used to color regions).

This filter is specialized for polygonal data. This means it runs a bit faster and is easier to construct visualization networks that process polygonal data.

The behavior of vtkPolyDataConnectivityFilter can be modified by turning on the boolean ivar ScalarConnectivity. If this flag is on, the connectivity algorithm is modified so that cells are considered connected only if 1) they are geometrically connected (share a point) and 2) the scalar values of one of the cell's points falls in the scalar range specified. This use of ScalarConnectivity is particularly useful for selecting cells for later processing.

To create an instance of class vtkPolyDataConnectivityFilter, simply invoke its constructor as follows

  obj = vtkPolyDataConnectivityFilter

Methods

The class vtkPolyDataConnectivityFilter has several methods that can be used. They are listed below. Note that the documentation is translated automatically from the VTK sources, and may not be completely intelligible. When in doubt, consult the VTK website. In the methods listed below, obj is an instance of the vtkPolyDataConnectivityFilter class.