WCRectTool.h

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//# WCRectTool.h: Base class for WorldCanvas event-based rectangle tools
//# Copyright (C) 1999,2000
//# Associated Universities, Inc. Washington DC, USA.
//#
//# This library is free software; you can redistribute it and/or modify it
//# under the terms of the GNU Library General Public License as published by
//# the Free Software Foundation; either version 2 of the License, or (at your
//# option) any later version.
//#
//# This library is distributed in the hope that it will be useful, but WITHOUT
//# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
//# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
//# License for more details.
//#
//# You should have received a copy of the GNU Library General Public License
//# along with this library; if not, write to the Free Software Foundation,
//# Inc., 675 Massachusetts Ave, Cambridge, MA 02139, USA.
//#
//# Correspondence concerning AIPS++ should be addressed as follows:
//#        Internet email: aips2-request@nrao.edu.
//#        Postal address: AIPS++ Project Office
//#                        National Radio Astronomy Observatory
//#                        520 Edgemont Road
//#                        Charlottesville, VA 22903-2475 USA
//#
//# $Id$

#ifndef TRIALDISPLAY_WCRECTTOOL_H
#define TRIALDISPLAY_WCRECTTOOL_H

#include <casa/aips.h>
#include <display/DisplayEvents/WCTool.h>
#include <display/DisplayEvents/DTVisible.h>

namespace casa { //# NAMESPACE CASA - BEGIN

// <summary>
// Base class for WorldCanvas event-based rectangle tools
// </summary>
//
// <use visibility=export>
//
// <reviewed reviewer="" date="yyyy/mm/dd" tests="" demos="">
// </reviewed>
//
// <prerequisites>
//   <li> WCTool
// </prerequisites>
//
// <etymology>
// WCRectTool stands for WorldCanvas Rectangle Tool
// </etymology>
//
// <synopsis>
// This class adds to its base WCTool to provide a tool for drawing,
// resizing and moving rectangles on a WorldCanvas.  While WCRectTool
// is not abstract, it performs no useful function.  The programmer
// should derive from this class, and implement the functions
// doubleInside and doubleOutside, which are called when the user
// double-clicks the key or mouse button inside or outside an existing
// rectangle respectively.  It is up to the programmer to decide what
// double clicks inside and outside the rectangle correspond to,
// although it is recommended that a double click inside correspond to
// the main action of the tool, and a double click outside correspond
// to a secondary action of the tool, if indeed a secondary action
// exists.
//
// The rectangle is drawn by dragging the mouse from one corner to
// the diagonally opposite corner.  Once constructed, the rectangle
// can be resized by dragging its corners, or relocated by dragging
// inside the rectangle.  The rectangle is removed from the display
// when the Esc key is pressed.
// </synopsis>
//
// <example>
// </example>
//
// <motivation>
// Many activities on the WorldCanvas will be based on the user drawing
// a rectangle, and then proceeding to some action with that rectangle.
// A nice example is zooming.
// </motivation>
//
// <todo asof="1999/07/23">
//   <li> Add time constraint to double click detection
// </todo>

        class WCRectTool : public WCTool, public DTVisible {

        public:

                // Constructor
                WCRectTool(WorldCanvas *wcanvas,
                           Display::KeySym keysym = Display::K_Pointer_Button1,
                           const Bool persistent = False);

                // Destructor
                virtual ~WCRectTool();

                // Switch the tool off - this calls the base class disable, and
                // then erases the rectangle if it's around
                virtual void disable();

                // Functions called by the local event handling operators -
                // these handle the drawing of the rectangle.  In special
                // conditions, namely double clicking the key, they will
                // pass control on to the doubleInside and doubleOutside
                // functions
                // <group>
                virtual void keyPressed(const WCPositionEvent &ev);
                virtual void keyReleased(const WCPositionEvent &ev);
                virtual void otherKeyPressed(const WCPositionEvent &ev);
                virtual void moved(const WCMotionEvent &ev, const viewer::region::region_list_type & /*selected_regions*/);
                virtual void refresh(const WCRefreshEvent &ev);
                // </group>

                // Functions special to the rectangle event handling - called when
                // there is a double click inside/outside the rectangle
                // <group>
                virtual void doubleInside() { };
                virtual void doubleOutside() { };
                // </group>

                // Functions called when a rectangle is ready and not being
                // editted, and when this status changes
                // <group>
                virtual void rectangleReady() { };
                virtual void rectangleNotReady() { };
                // </group>

                // Retrieve the rectangle corners
                virtual void get(Int &x1, Int &y1, Int &x2, Int &y2) const ;

        private:

                // do the rectangles persist after double clicks?
                Bool itsRectanglePersistent;

                // is the rectangle on screen?
                Bool itsOnScreen;

                // are we actively zooming?
                Bool itsActive;

                // have we moved?
                Bool itsMoved;

                // do we have a rectangle drawn yet?
                Bool itsRectangleExists;

                // adjustment mode
                enum AdjustMode {
                    Off,
                    Move
                };
                WCRectTool::AdjustMode itsAdjustMode;

                // coordinates of the rectangle: pixel and world
                // <group>
                Int itsX1, itsY1, itsX2, itsY2;
                Vector<Double> itsStoredWorldBlc, itsStoredWorldTrc;
                // </group>

                // set the coordinates of the rectangle
                // <group>
                virtual void set(const Int &x1, const Int &y1, const Int &x2, const Int &y2);
                // </group>

                // set/get only the anchor point
                // <group>
                virtual void set(const Int &x1, const Int &y1);
                virtual void get(Int &x1, Int &y1) const ;
                // </group>

                // preserve/restore the world coordinates
                // <group>
                virtual void preserve();
                virtual void restore();
                // </group>

                // draw the rubberband box on a PixelCanvas
                virtual void draw(const Bool drawHandles = False);

                // reset this drawer
                virtual void reset();

                // storage of the handle coordinates
                Vector<Int> itsHX, itsHY;

                // position that move started from
                Int itsBaseMoveX, itsBaseMoveY;

                // position of last press event
                Int itsLastPressX, itsLastPressY;
                Int its2ndLastPressX, its2ndLastPressY;

                // position of last release event
                Int itsLastReleaseX, itsLastReleaseY;

                // store the times of the last two presses here:
                Double itsLastPressTime, its2ndLastPressTime;

        };


} //# NAMESPACE CASA - END

#endif