mousegesturerecognizer.h

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/*
 * This file is part of the mouse gesture package.
 * Copyright (C) 2006 Johan Thelin <e8johan@gmail.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the
 * following conditions are met:
 *
 *   - Redistributions of source code must retain the above
 *     copyright notice, this list of conditions and the
 *     following disclaimer.
 *   - Redistributions in binary form must reproduce the
 *     above copyright notice, this list of conditions and
 *     the following disclaimer in the documentation and/or
 *     other materials provided with the distribution.
 *   - The names of its contributors may be used to endorse
 *     or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */
 
#ifndef MOUSEGESTURERECOGNIZER_H
#define MOUSEGESTURERECOGNIZER_H
 
#include <list>
#include <vector>
 
namespace Gesture
{
 
/*
 *  Sub-class and implement callback method and register along a gesture description.
 */
class MouseGestureCallback
{
public:
    virtual void callback() = 0;
    virtual ~MouseGestureCallback() { }
};
 
/*
 *  The available directions.
 */
typedef enum { Up, Down, Left, Right, AnyHorizontal, AnyVertical, UpLeft, UpRight, DownLeft, DownRight, NoMatch } Direction;
/*
 *  A list of directions.
 */
typedef std::list<Direction> DirectionList;
 
/*
 *  Create lists of directions and connect to a callback.
 */
struct GestureDefinition {
    GestureDefinition(const DirectionList &d, MouseGestureCallback* c) : directions(d), callbackClass(c) {}
 
    DirectionList directions;
    MouseGestureCallback* callbackClass;
};
 
/*
 *  Data types for internal use
 */
struct Pos {
    Pos(int ix, int iy) : x(ix), y(iy) {}
 
    int x, y;
};
 
typedef std::vector<Pos> PosList;
typedef std::vector<GestureDefinition> GestureList;
 
class MouseGestureRecognizer
{
public:
    MouseGestureRecognizer(int minimumMovement = 5, double minimumMatch = 0.9, bool allowDiagonals = false);
    ~MouseGestureRecognizer();
 
    void addGestureDefinition(const GestureDefinition &gesture);
    void clearGestureDefinitions();
 
    void startGesture(int x, int y);
    void addPoint(int x, int y);
    bool endGesture(int x, int y);
    void abortGesture();
    PosList currentPath() const;
private:
    bool recognizeGesture();
 
    static PosList limitDirections(const PosList &positions, bool allowDiagnonals);
    static PosList simplify(const PosList &positions);
    static PosList removeShortest(const PosList &positions);
    static int calcLength(const PosList &positions);
 
    struct Private;
    Private* d;
};
 
};
 
#endif // MOUSEGESTURERECOGNIZER_H