vtkImplicitFunction

Section: Visualization Toolkit Common Classes

Usage

vtkImplicitFunction specifies an abstract interface for implicit functions. Implicit functions are real valued functions defined in 3D space, w = F(x,y,z). Two primitive operations are required: the ability to evaluate the function, and the function gradient at a given point. The implicit function divides space into three regions: on the surface (F(x,y,z)=w), outside of the surface (F(x,y,z)>c), and inside the surface (F(x,y,z)<c). (When c is zero, positive values are outside, negative values are inside, and zero is on the surface. Note also that the function gradient points from inside to outside.)

Implicit functions are very powerful. It is possible to represent almost any type of geometry with the level sets w = const, especially if you use boolean combinations of implicit functions (see vtkImplicitBoolean).

vtkImplicitFunction provides a mechanism to transform the implicit function(s) via a vtkAbstractTransform. This capability can be used to translate, orient, scale, or warp implicit functions. For example, a sphere implicit function can be transformed into an oriented ellipse.

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

  obj = vtkImplicitFunction

Methods

The class vtkImplicitFunction 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 vtkImplicitFunction class.