/*

* Copyright (c) 2006-2007 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:   Definition of CHuiMatrixStack. CHuiMatrixStack is a stack of 

*                2D transformation matrices.

*

*/

#ifndef __HUIMATRIXSTACK_H__

#define __HUIMATRIXSTACK_H__

#include <e32base.h>

#include "uiacceltk/HuiRealPoint.h"

/**

 * Stack of 2D transformation matrices.

 */

NONSHARABLE_CLASS(CHuiMatrixStack) : public CBase

    {

public:

    /** 2D transformation matrix. */

    struct TMatrix

        {   

    public:        

        TReal32 iMatrix[9];       

        /** Matrix is an identity matrix. Multiplication can be skipped. */

        TBool iIsIdentity;

    public:

        /** Constructor that initializes the matrix as an identity matrix. */

        IMPORT_C TMatrix();

        /**

         * Multiplies this matrix with another one. Result is stored in this

         * matrix.

         *

         * @param aOther  Matrix to multiply with.

         */

        void Multiply(const TMatrix& aOther);

        /**

         * Multiplies a point with the matrix.

         *

         * @param aPoint  2D point. Modified.

         */

        IMPORT_C void Multiply(THuiRealPoint& aPoint) const;

        };

public:

    /* Constructors and destructor. */

    IMPORT_C static CHuiMatrixStack* NewL();

    static CHuiMatrixStack* NewLC();

    /**

     * Destructor.

     */

    virtual ~CHuiMatrixStack();

    /* Methods. */

    IMPORT_C TInt Count() const;

    IMPORT_C TMatrix& Current();

    /**

     * @return  Error code.

     */

    IMPORT_C TInt Push();

    IMPORT_C void Pop();

    IMPORT_C void LoadIdentity();

    IMPORT_C void Multiply(const TMatrix& aMatrix);    

protected:

    /* Constructors. */

    CHuiMatrixStack();

    void ConstructL();    

private:

    // Typedef for convenience.

    typedef RArray<TMatrix> RMatrixStack;

    RMatrixStack iStack;            

    };

#endif // __HUIMATRIXSTACK_H__