vtkAxisActor2D

Section: Visualization Toolkit Rendering Classes

Usage

vtkAxisActor2D creates an axis with tick marks, labels, and/or a title, depending on the particular instance variable settings. vtkAxisActor2D is a 2D actor; that is, it is drawn on the overlay plane and is not occluded by 3D geometry. To use this class, you typically specify two points defining the start and end points of the line (x-y definition using vtkCoordinate class), the number of labels, and the data range (min,max). You can also control what parts of the axis are visible including the line, the tick marks, the labels, and the title. You can also specify the label format (a printf style format).

This class decides what font size to use and how to locate the labels. It also decides how to create reasonable tick marks and labels. The number of labels and the range of values may not match the number specified, but should be close.

Labels are drawn on the "right" side of the axis. The "right" side is the side of the axis on the right as you move from Position to Position2. The way the labels and title line up with the axis and tick marks depends on whether the line is considered horizontal or vertical.

The vtkActor2D instance variables Position and Position2 are instances of vtkCoordinate. Note that the Position2 is an absolute position in that class (it was by default relative to Position in vtkActor2D).

What this means is that you can specify the axis in a variety of coordinate systems. Also, the axis does not have to be either horizontal or vertical. The tick marks are created so that they are perpendicular to the axis.

Set the text property/attributes of the title and the labels through the vtkTextProperty objects associated to this actor.

To create an instance of class vtkAxisActor2D, simply invoke its constructor as follows

  obj = vtkAxisActor2D

Methods

The class vtkAxisActor2D 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 vtkAxisActor2D class.