vtkConnectivityFilter - extract data based on geometric connectivity

Super Class: vtkDataSetToUnstructuredGridFilter

Description:

vtkConnectivityFilter is a filter that extracts cells that share common points and/or meet other connectivity criterion. (Cells that share vertices and meet other connectivity criterion such as scalar range are known as 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 the data by region). vtkConnectivityFilter is generalized to handle any type of input dataset. It generates output data of type vtkUnstructuredGrid. If you know that your input type is vtkPolyData, you may wish to use vtkPolyDataConnectivityFilter. The behavior of vtkConnectivityFilter 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 volume datasets: it can be used as a simple "connected segmentation" algorithm. For example, by using a seed voxel (i.e., cell) on a known anatomical structure, connectivity will pull out all voxels "containing" the anatomical structure. These voxels can then be contoured or processed by other visualization filters.

See Also:

vtkPolyDataConnectivityFilter

Methods:

Detailed Method Descriptions: