vtkGeometryFilter - extract geometry from data (or convert data to polygonal type)

Super Class: vtkDataSetToPolyDataFilter

Description:

vtkGeometryFilter is a general-purpose filter to extract geometry (and associated data) from any type of dataset. Geometry is obtained as follows: all 0D, 1D, and 2D cells are extracted. All 2D faces that are used by only one 3D cell (i.e., boundary faces) are extracted. It also is possible to specify conditions on point ids, cell ids, and on bounding box (referred to as "Extent") to control the extraction process. This filter also may be used to convert any type of data to polygonal type. The conversion process may be less than satisfactory for some 3D datasets. For example, this filter will extract the outer surface of a volume or structured grid dataset. (For structured data you may want to use vtkStructuredPointsGeometryFilter, vtkStructuredGridGeometryFilter, vtkUnstructuredGridGeometryFilter, vtkRectilinearGridGeometryFilter, or vtkExtractVOI.)

Caveats:

When vtkGeometryFilter extracts cells (or boundaries of cells) it will (by default) merge duplicate vertices. This may cause problems in some cases. For example, if you've run vtkPolyDataNormals to generate normals, which may split meshes and create duplicate vertices, vtkGeometryFilter will merge these points back together. Turn merging off to prevent this from occuring.

See Also:

vtkStructuredPointsGeometryFilter vtkStructuredGridGeometryFilter vtkExtractGeometry vtkExtractVOI

Methods:

Detailed Method Descriptions: