FreeMat
vtkTerrainContourLineInterpolator

Section: Visualization Toolkit Widget Classes

Usage

vtkTerrainContourLineInterpolator interpolates nodes on height field data. The class is meant to be used in conjunciton with a vtkContourWidget, enabling you to draw paths on terrain data. The class internally uses a vtkProjectedTerrainPath. Users can set kind of interpolation desired between two node points by setting the modes of the this filter. For instance:

 contourRepresentation->SetLineInterpolator(interpolator);
 interpolator->SetImageData( demDataFile );
 interpolator->GetProjector()->SetProjectionModeToHug();
 interpolator->SetHeightOffset(25.0);

You are required to set the ImageData to this class as the height-field image.

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

  obj = vtkTerrainContourLineInterpolator

Methods

The class vtkTerrainContourLineInterpolator 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 vtkTerrainContourLineInterpolator class.

  • string = obj.GetClassName () - Standard methods for instances of this class.
  • int = obj.IsA (string name) - Standard methods for instances of this class.
  • vtkTerrainContourLineInterpolator = obj.NewInstance () - Standard methods for instances of this class.
  • vtkTerrainContourLineInterpolator = obj.SafeDownCast (vtkObject o) - Standard methods for instances of this class.
  • int = obj.InterpolateLine (vtkRenderer ren, vtkContourRepresentation rep, int idx1, int idx2) - Interpolate to create lines between contour nodes idx1 and idx2. Depending on the projection mode, the interpolated line may either hug the terrain, just connect the two points with a straight line or a non-occluded interpolation. Used internally by vtkContourRepresentation.
  • int = obj.UpdateNode (vtkRenderer , vtkContourRepresentation , double , int ) - The interpolator is given a chance to update the node. Used internally by vtkContourRepresentation Returns 0 if the node (world position) is unchanged.
  • obj.SetImageData (vtkImageData ) - Set the height field data. The height field data is a 2D image. The scalars in the image represent the height field. This must be set.
  • vtkImageData = obj.GetImageData () - Set the height field data. The height field data is a 2D image. The scalars in the image represent the height field. This must be set.
  • vtkProjectedTerrainPath = obj.GetProjector () - Get the vtkProjectedTerrainPath operator used to project the terrain onto the data. This operator has several modes, See the documentation of vtkProjectedTerrainPath. The default mode is to hug the terrain data at 0 height offset.