vtkLODActor

Section: Visualization Toolkit Rendering Classes

Usage

vtkLODActor is an actor that stores multiple levels of detail (LOD) and can automatically switch between them. It selects which level of detail to use based on how much time it has been allocated to render. Currently a very simple method of TotalTime/NumberOfActors is used. (In the future this should be modified to dynamically allocate the rendering time between different actors based on their needs.)

There are three levels of detail by default. The top level is just the normal data. The lowest level of detail is a simple bounding box outline of the actor. The middle level of detail is a point cloud of a fixed number of points that have been randomly sampled from the mapper's input data. Point attributes are copied over to the point cloud. These two lower levels of detail are accomplished by creating instances of a vtkOutlineFilter (low-res) and vtkMaskPoints (medium-res). Additional levels of detail can be add using the AddLODMapper() method.

To control the frame rate, you typically set the vtkRenderWindowInteractor DesiredUpdateRate and StillUpdateRate. This then will cause vtkLODActor to adjust its LOD to fulfill the requested update rate.

For greater control on levels of detail, see also vtkLODProp3D. That class allows arbitrary definition of each LOD.

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

  obj = vtkLODActor

Methods

The class vtkLODActor 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 vtkLODActor class.