WCRTZoomer.h

Classes

WCRTZoomer -- WorldCanvas event-based zoomer (full description)

class WCRTZoomer : public WCRectTool

Interface

Public Members
WCRTZoomer(WorldCanvas *wcanvas, Display::KeySym keysym = Display::K_Pointer_Button1)
virtual ~WCRTZoomer()
virtual void doubleInside()
virtual void doubleOutside()
virtual void zoomed(const Vector<Double> &linBlc, const Vector<Double> &linTrc)
Private Members
void getLinearCoords(Vector<Double> &blc, Vector<Double> &trc)

Description

  • WCRectTool

    Etymology

    WCRTZoomer stands for WorldCanvas Rectangling Tool Zoomer

    Synopsis

    This class finalises the functionality in WCRectTool to implement event-based zooming on a WorldCanvas. Double clicking inside the constructed rectangle results in zooming in; double clicking outside the rectangle gives zooming out.

    Example

    Motivation

    Zooming is an essential tool for interacting with data displays.

    To Do

    Member Description

    WCRTZoomer(WorldCanvas *wcanvas, Display::KeySym keysym = Display::K_Pointer_Button1)

    Constructor

    virtual ~WCRTZoomer()

    Destructor

    virtual void doubleInside()
    virtual void doubleOutside()

    Functions specific to the zooming - these are called by lower-level event handlers in the base classes

    virtual void zoomed(const Vector<Double> &linBlc, const Vector<Double> &linTrc)

    This function is called when a zoom occurs. It is supplied with the linear coords of the new zoom box, and thus can be implemented to do further actions, or perhaps report the new zoom box to the application

    void getLinearCoords(Vector<Double> &blc, Vector<Double> &trc)

    get the linear coords of the current zoom box