vtkGaussianSplatter

Section: Visualization Toolkit Imaging Classes

Usage

vtkGaussianSplatter is a filter that injects input points into a structured points (volume) dataset. As each point is injected, it "splats" or distributes values to nearby voxels. Data is distributed using an elliptical, Gaussian distribution function. The distribution function is modified using scalar values (expands distribution) or normals (creates ellipsoidal distribution rather than spherical).

In general, the Gaussian distribution function f(x) around a given splat point p is given by

f(x) = ScaleFactor * exp( ExponentFactor*((r/Radius)**2) )

where x is the current voxel sample point; r is the distance |x-p| ExponentFactor <= 0.0, and ScaleFactor can be multiplied by the scalar value of the point p that is currently being splatted.

If points normals are present (and NormalWarping is on), then the splat function becomes elliptical (as compared to the spherical one described by the previous equation). The Gaussian distribution function then becomes: f(x) = ScaleFactor * exp( ExponentFactor*( ((rxy/E)**2 + z**2)/R**2) )

where E is a user-defined eccentricity factor that controls the elliptical shape of the splat; z is the distance of the current voxel sample point along normal N; and rxy is the distance of x in the direction prependicular to N.

This class is typically used to convert point-valued distributions into a volume representation. The volume is then usually iso-surfaced or volume rendered to generate a visualization. It can be used to create surfaces from point distributions, or to create structure (i.e., topology) when none exists.

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

  obj = vtkGaussianSplatter

Methods

The class vtkGaussianSplatter 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 vtkGaussianSplatter class.