vtkPiecewiseFunction

Section: Visualization Toolkit Filtering Classes

Usage

Defines a piecewise function mapping. This mapping allows the addition of control points, and allows the user to control the function between the control points. A piecewise hermite curve is used between control points, based on the sharpness and midpoint parameters. A sharpness of 0 yields a piecewise linear function and a sharpness of 1 yields a piecewise constant function. The midpoint is the normalized distance between control points at which the curve reaches the median Y value. The midpoint and sharpness values specified when adding a node are used to control the transition to the next node (the last node's values are ignored) Outside the range of nodes, the values are 0 if Clamping is off, or the nearest node point if Clamping is on. Using the legacy methods for adding points (which do not have Sharpness and Midpoint parameters) will default to Midpoint = 0.5 (halfway between the control points) and Sharpness = 0.0 (linear).

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

  obj = vtkPiecewiseFunction

Methods

The class vtkPiecewiseFunction 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 vtkPiecewiseFunction class.