FreeMat: vtkSpatialRepresentationFilter

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vtkSpatialRepresentationFilter

Section: Visualization Toolkit Graphics Classes

# Usage

vtkSpatialRepresentationFilter generates an polygonal representation of a spatial search (vtkLocator) object. The representation varies depending upon the nature of the spatial search object. For example, the representation for vtkOBBTree is a collection of oriented bounding boxes. Ths input to this filter is a dataset of any type, and the output is polygonal data. You must also specify the spatial search object to use.

Generally spatial search objects are used for collision detection and other geometric operations, but in this filter one or more levels of spatial searchers can be generated to form a geometric approximation to the input data. This is a form of data simplification, generally used to accelerate the rendering process. Or, this filter can be used as a debugging/ visualization aid for spatial search objects.

This filter can generate one or more output vtkPolyData corresponding to different levels in the spatial search tree. The output data is retrieved using the GetOutput(id) method, where id ranges from 0 (root level) to Level. Note that the output for level "id" is not computed unless a GetOutput(id) method is issued. Thus, if you desire three levels of output (say 2,4,7), you would have to invoke GetOutput(2), GetOutput(4), and GetOutput(7). (Also note that the Level ivar is computed automatically depending on the size and nature of the input data.) There is also another GetOutput() method that takes no parameters. This method returns the leafs of the spatial search tree, which may be at different levels.

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

      obj = vtkSpatialRepresentationFilter

# Methods

The class vtkSpatialRepresentationFilter 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 vtkSpatialRepresentationFilter class.

- `string = obj.GetClassName ()`
- `int = obj.IsA (string name)`
- `vtkSpatialRepresentationFilter = obj.NewInstance ()`
- `vtkSpatialRepresentationFilter = obj.SafeDownCast (vtkObject o)`
- `obj.SetSpatialRepresentation (vtkLocator )` - Set/Get the locator that will be used to generate the representation.
- `vtkLocator = obj.GetSpatialRepresentation ()` - Set/Get the locator that will be used to generate the representation.
- `int = obj.GetLevel ()` - Get the maximum number of outputs actually available.
- `vtkPolyData = obj.GetOutput (int level)` - A special form of the GetOutput() method that returns multiple outputs.
- `vtkPolyData = obj.GetOutput ()` - Output of terminal nodes/leaves.
- `obj.ResetOutput ()` - Reset requested output levels
- `obj.SetInput (vtkDataSet input)` - Set / get the input data or filter.
- `vtkDataSet = obj.GetInput ()` - Set / get the input data or filter.