/*

* Copyright (c) 2007 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:   Viewport visual.

*

*/

#ifndef C_HUIVIEWPORTLAYOUT_H

#define C_HUIVIEWPORTLAYOUT_H

#include <e32base.h>

#include <uiacceltk/HuiLayout.h>

/* Forward declarations */

class CHuiEnv;

/**

 * A CHuiViewportLayout is similar to a CHuiDeckLayout, but it can contain

 * visuals larger than itself. The larger visuals can be scrolled around.

 *

 * The viewport visual can be thought of as providing a "window" onto a larger visual.

 * Different parts of the visual can be viewed by moving the viewport. By default, the

 * clipping region is enabled.

 *

 * To use the viewport visual, you first need to call SetVirtualSize() to define the

 * coordinate system for the visual. You pass in the work area of the visual, in whatever

 * units you choose. For example, if you set the virtual work area size to (1.0, 1.0), it

 * will use a normalised (u, v) coordinate mapping system.

 *

 * Next, you can set the dimensions and position of the viewport (or "window") using SetViewportSize()

 * and SetViewportPos(). This viewport can be moved around the virtual work area. The contents of the

 * viewport will be fitted to the ViewportVisual.

 *

 * Possible uses for CHuiViewportVisual are for text marquee scrolling effects and photo zooming.

 *

 * @todo - insert diagram here.

 * @see CHuiDeckLayout

 *

 */

NONSHARABLE_CLASS(CHuiViewportLayout) : public CHuiLayout

	{

public:	

    /** @beginAPI */

    // Bitfield of binary flags.

	enum TFlags

		{

		/** Wrap contents of visual horizontally. */

		EWrapHorizontal = 0x0001,

		/** Wrap contents of visual vertically. */

		EWrapVertical = 0x0002

		};

    /* Constructors and destructor. */

    /**

     * Construct a new viewport layout and give its ownership to a control.

     *

     * @param aOwnerControl  Owner control.

     * @param aParentLayout  Parent layout for the new deck layout.

     */

    IMPORT_C static CHuiViewportLayout* AddNewL(CHuiControl& aOwnerControl, 

                                                CHuiLayout* aParentLayout = 0);

    /** @endAPI */

public:

    /**

     * Constructor.

     *

     * @param aOwner  Owner control.

     */

    CHuiViewportLayout(MHuiVisualOwner& aOwner);    // Made public for unit tests.

    void ConstructL();  // Made public for unit tests.

    ~CHuiViewportLayout();  // Made public for unit tests.

public:

    /** @beginAPI */

    /* Methods. */

	/**

	 * Set virtual size of the viewable area.

	 *

	 * This is different from the physical size of the viewport -

	 * it defines the coordinate space that is used for scrolling.

	 * To use a normalised (u, v) coordinate mapping system, set aSize to (,1.0, 1.0).

	 *

	 * @param aSize The bottom-right corner of the child visual, in the units you wish to use for positioning the viewport.

	 * @param aTransitionTime The time it will take to complete the resizing of the virtual size.

	 */

	IMPORT_C void SetVirtualSize(const THuiRealSize& aSize, TInt aTransitionTime=0);

	/**

	 * Set size of the viewport area.

	 *

	 * This is the size of the "window" we are using to look at the visual.

	 *

	 * @param aSize The size of the viewport in the units defined by SetVirtualSize().

	 * @param aTransitionTime The time it will take to complete the resizing of the viewport area.

	 * @see SetVirtualSize, SetViewportPos

	 */

	IMPORT_C void SetViewportSize(const THuiRealSize& aSize, TInt aTransitionTime=0);

	/**

	 * Set position of the viewport area.

	 *

	 * This is the offset of the "window" we are using to look at the visual.

	 *

	 * @param aSize The size of the viewport in the units defined by SetVirtualSize().

	 * @param aTransitionTime The time it will take to complete moving the viewport area.

	 * @see SetVirtualSize, SetViewportSize

	 */

	IMPORT_C void SetViewportPos(const THuiRealPoint& aSize, TInt aTransitionTime=0);

    /** @endAPI */

    /**

     * Overridden version of size changing updates the layout of child visuals.

     *

     * @param aSize  New size for the layout.

     * @param aTransitionTime  Time for the transition to new size to take 

     *                          place.

     */

    void SetSize(const THuiRealSize& aSize, TInt aTransitionTime=0);

    TBool ChildSize(TInt aOrdinal, TSize& aSize);

    TBool ChildPos(TInt aOrdinal, TPoint& aPos);

    TInt ChildRect(TInt aOrdinal, THuiRealRect& aRect);

    void GetClassName(TDes& aName) const

        {

        aName = _L("CViewportLayout");

        }

private: 

    /** The bottom-right corner of the child visual, in the units defined by SetVirtualSize. */

    THuiRealSize iVirtualSize;

    /** The top-left corner of the viewport window, relative to te position defined by iVirtualSize. */

    THuiRealPoint iViewportPos;

    /** The size of the viewport window, relative to te position defined by iVirtualSize. */

    THuiRealSize iViewportSize;

    /** Bitfield of flags to change the way the vieport is rendered. */

    TInt iWrappingFlags;

	};

#endif // C_HUIVIEWPORTLAYOUT_H