/*

* Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:    Definition of TGlxZoomLayoutBase

*

*/

#ifndef GLXZOOMLAYOUTBASE_H

#define GLXZOOMLAYOUTBASE_H

// INCLUDES

#include <glxlayout.h>

// FORWARD DECLARATIONS

struct TAlfRealRect;

// CLASS DECLARATION

/**

* Abtract base class for zooming layouts.  Sets layout values based on

* coordinates provided by the derived class.

*

* @internal reviewed 06/06/2007 by Kimmo Hoikka

*/

class TGlxZoomLayoutBase : public TGlxLayout

    {

    public:  // Constructors and destructor

        /**

        * C++ default constructor.

        */

        IMPORT_C TGlxZoomLayoutBase();

        /**

        * Destructor.

        */

        IMPORT_C ~TGlxZoomLayoutBase();

    public: // New functions

        /**

        * Set the image dimensions.

        * @param aDimensions Dimensions of the image being zoomed (in pixels)

        */

        IMPORT_C void SetImageDimensions(const TSize& aDimensions);

        /**

        * Get the image dimensions.

        * @return const TSize& Dimensions of the image being zoomed (in pixels)

        */

        IMPORT_C const TSize& ImageDimensions() const;

        /**

        * Get current zoom and pan values.  The returned rectangle is relative

        * to the screen, ie. if the width is 2, the visual should be twice the

        * width of the screen, and if the centre of the rectangle is (0, 0) the

        * visual should be centred on the screen. If the rectangle is

        * (-0.5, -0.5) - (0.5, 0.5) then the visual should exactly fill the

        * screen.

        * @param aRect Reference to rect in which to return coords.

        */

        virtual void GetCurrentCoords(TAlfRealRect& aRect) = 0;

        /**

        * Get "predicted" zoom and pan values.  These are the values that would

        * eventually be reached if the user released all zoom/pan keys now.

        * @param aRect Reference to rect in which to return coords.

        */

        virtual void GetPredictedCoords(TAlfRealRect& aRect) = 0;

    protected:  // From TGlxLayout

        /** See @ref TGlxLayout::DoSetLayoutValues */

        IMPORT_C void DoSetLayoutValues(TGlxLayoutInfo& aInfo);

        /** See @ref TGlxLayout::DoChanged */

        IMPORT_C TBool DoChanged() const;

        /** See @ref TGlxLayout::DoClearChanged */

        IMPORT_C void DoClearChanged();

    protected:  // Data

        /** Dimensions of the image being zoomed (in pixels) */

        TSize iImageDimensions;

    private:    // Data

        /** Whether the layout has changed since last refresh */

        TBool iChanged;

    };

#endif  // GLXZOOMLAYOUTBASE_H

// End of File