vtkAreaPicker

Section: Visualization Toolkit Rendering Classes

Usage

The vtkAreaPicker picks all vtkProp3Ds that lie behind the screen space rectangle from x0,y0 and x1,y1. The selection is based upon the bounding box of the prop and is thus not exact.

Like vtkPicker, a pick results in a list of Prop3Ds because many props may lie within the pick frustum. You can also get an AssemblyPath, which in this case is defined to be the path to the one particular prop in the Prop3D list that lies nearest to the near plane.

This picker also returns the selection frustum, defined as either a vtkPlanes, or a set of eight corner vertices in world space. The vtkPlanes version is an ImplicitFunction, which is suitable for use with the vtkExtractGeometry. The six frustum planes are in order: left, right, bottom, top, near, far

Because this picker picks everything within a volume, the world pick point result is ill-defined. Therefore if you ask this class for the world pick position, you will get the centroid of the pick frustum. This may be outside of all props in the prop list.

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

  obj = vtkAreaPicker

Methods

The class vtkAreaPicker 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 vtkAreaPicker class.