/*

* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, version 2.1 of the License.

* 

* This program 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 Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser General Public License

* along with this program.  If not, 

* see "http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html/".

*

* Description:

*

*/

#ifndef QSTMZOOMGESTURERECOGNISER_H_

#define QSTMZOOMGESTURERECOGNISER_H_

#include <qstmgestureengine_if.h>

#include <qstmgesture_if.h>

#include <qstmgesturelistener_if.h>

namespace qstmGesture

{

/*!

 * QStm_ZoomGestureRecogniser handles zoomin gesture: start from near lower left / upper right corner and drag

 * This is useful if one wants to implement single handed zooming so can be done using thumb

 * (no need to use pinch i.e. hold device in one hand and use two fingers of the other)

 * Current spec is:

 * - touch lower left corner and start dragging => initialize ZOOM IN

 * - touch upper right corner and start dragging => initialize ZOOM OUT

 * store the touch point and then calculate the distance until release

 * The distance is the zoom factor (probably needs some adjustment, not just the pixels...)

 */

class QStm_ZoomGestureRecogniser : public QStm_GestureRecogniser

{

public:

	static const QStm_GestureUid KUid = EGestureUidCornerZoom;

	virtual ~QStm_ZoomGestureRecogniser();

	virtual QStm_GestureRecognitionState recognise(int numOfActiveStreams, QStm_GestureEngineIf* ge) ;

	virtual void release(QStm_GestureEngineIf* ge) ;

	virtual QStm_GestureUid gestureUid() const { return KUid; }

	/*!

	 * Additional methods to set up zoom in gesture recogniser:

	 * define the rectangle where the lower left corner is

	 * \param theArea

	 */

	void setArea(const QRect& theArea) ;

	/*!

	 * Additional methods to set up zoom in gesture recogniser:

	 * Define how close to the lower left corner the touch must happen

	 * \param rangeInPixels

	 */

	void setRange(int rangeInMm) ;

	QStm_ZoomGestureRecogniser(QStm_GestureListenerIf* listener) ;

	float calculateDistance(const QPoint& aTp) ;

	int adjustZoom(float& previousDistance, float newDistance) ;

private:

	QRect         m_area ;

	int           m_rangesizeInPixels ;

	QStm_ZoomType m_zoomtype ;

	bool          m_zooming ;

	QPoint        m_startingtouch ;

	QPoint        m_previoustouch ;

	int           m_delta ;

};

} // namespace

#endif /* QSTMZOOMGESTURERECOGNISER_H_ */