FreeMat

- Main Page
- Related Pages

vtkRectilinearWipeWidget

Section: Visualization Toolkit Widget Classes

# Usage

The vtkRectilinearWipeWidget is used to interactively control an instance of vtkImageRectilinearWipe (and an associated vtkImageActor used to display the rectilinear wipe). A rectilinear wipe is a 2x2 checkerboard pattern created by combining two separate images, where various combinations of the checker squares are possible. Using this widget, the user can adjust the layout of the checker pattern, such as moving the center point, moving the horizontal separator, or moving the vertical separator. These capabilities are particularly useful for comparing two images.

To use this widget, specify its representation (by default the representation is an instance of vtkRectilinearWipeProp). The representation generally requires that you specify an instance of vtkImageRectilinearWipe and an instance of vtkImageActor. Other instance variables may also be required to be set – see the documentation for vtkRectilinearWipeProp (or appropriate subclass).

By default, the widget responds to the following events:

     Selecting the center point, horizontal separator, and verticel separator:
       LeftButtonPressEvent - move the separators
       LeftButtonReleaseEvent - release the separators
       MouseMoveEvent - move the separators

Selecting the center point allows you to move the horizontal and vertical separators simultaneously. Otherwise only horizontal or vertical motion is possible/

Note that the event bindings described above can be changed using this class's vtkWidgetEventTranslator. This class translates VTK events into the vtkRectilinearWipeWidget's widget events:

       vtkWidgetEvent::Select – some part of the widget has been selected
       vtkWidgetEvent::EndSelect – the selection process has completed
       vtkWidgetEvent::Move – a request for motion has been invoked

In turn, when these widget events are processed, the vtkRectilinearWipeWidget invokes the following VTK events (which observers can listen for):

       vtkCommand::StartInteractionEvent (on vtkWidgetEvent::Select)
       vtkCommand::EndInteractionEvent (on vtkWidgetEvent::EndSelect)
       vtkCommand::InteractionEvent (on vtkWidgetEvent::Move)

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

      obj = vtkRectilinearWipeWidget

# Methods

The class vtkRectilinearWipeWidget 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 vtkRectilinearWipeWidget class.

- `string = obj.GetClassName ()` - Standard macros.
- `int = obj.IsA (string name)` - Standard macros.
- `vtkRectilinearWipeWidget = obj.NewInstance ()` - Standard macros.
- `vtkRectilinearWipeWidget = obj.SafeDownCast (vtkObject o)` - Standard macros.
- `obj.SetRepresentation (vtkRectilinearWipeRepresentation r)` - Create the default widget representation if one is not set.
- `obj.CreateDefaultRepresentation ()` - Create the default widget representation if one is not set.