/*

* Copyright (c) 2004-2008 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:  Grayscales images.

*

*/

#ifndef AKNSRLEFFECTPLUGINGRAYSCALE_H

#define AKNSRLEFFECTPLUGINGRAYSCALE_H

//  INCLUDES

#include "AknsRlEffectPlugin.h"

#include <AknsRlEffect.h>

// CONSTANTS

// Effect plugin UID

const TInt KAknsRlEffectPluginGrayscaleUID = 0x10204AE3;

// Constants for parameter names

_LIT( KAknsRlEffectGrayscaleGrayMin, "min" );

_LIT( KAknsRlEffectGrayscaleGrayMax, "max" );

_LIT( KAknsRlEffectGrayscaleBlendFactor, "f" );

// CLASS DECLARATION

/**

* Grayscale provides functionality to grayscaling images.

*

* @since 2.8

*/

NONSHARABLE_CLASS(CAknsRlEffectPluginGrayscale):

    public CAknsRlEffectPlugin,

    public MAknsRlEffect

    {

    public: // Constructors and destructor

        /**

        * Default constructor.

        *

        * @since 2.8

        */

        CAknsRlEffectPluginGrayscale();

        /**

        * Destructor.

        *

        * @since 2.8

        */

        virtual ~CAknsRlEffectPluginGrayscale();

    public: // Implementation of CAknsEffectPlugin

        TUid EffectUid() const;

        MAknsRlEffect* Effect( const TInt aInterface );

    public: // Implementation of MAknsRlEffect

        void InitializeL();

        void Release();

        void ActivateL( MAknsRlEffectContext* aContext );

        void Deactivate();

        /**

        * Accepted named parameters:

        * - "min", integer, lower end of the scale range

        * - "max", integer, higher end of the scale range

        * - "f", integer, normal range [0, 255], blend factor.

        *

        * Min and Max:

        * The resulting gray shades will be scaled into range [min, max].  The

        * normal range for min and max is [0, 255] but values outside the range

        * work as expected. Warning: min > max will cause a leave.

        *

        * Blend factor:

        * Blend factor controls the resulting opacity of the applied effect.

        * Normal value range is [0, 255] but values outside will also work.

        * - Value 0 will result in the original image.

        * - Value 255 will result in the filtered image.

        * - Values outside range [0, 255] will result in underexposure or

        *   overexposure.

        *

        * The default parameter values are:

        * - "min" = 0

        * - "max" = 255

        * - "f" = 255, full filter opacity

        */

        void SetParametersL( MAknsRlParameterIterator& aParameters );

        /**

        * Supported modes:

        * - EColor64K -> EColor64K

        * - EColor16MU -> EColor16MU

        * - EColor64K -> EGray256

        * - EColor16MU -> EGray256

        *

        * Masks are ignored. Target layer and input layer A are both required.

        */

        void GetCapabilities( TAknsRlEffectCaps& aCaps );

        TInt Render( const TAknsRlRenderOpParam& aParam );

    private:

        MAknsRlEffectContext* iContext;

        TInt iGrayMin;

        TInt iGrayMax;

        TInt iBlendFactor;

    };

#endif // AKNSRLEFFECTPLUGINGRAYSCALE_H

// End of File