/*

* 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:   Gradient brush class

*

*/

#ifndef C_ALFGRADIENTBRUSH_H

#define C_ALFGRADIENTBRUSH_H

#include <alf/alfbrush.h>

#include <gdi.h>

class CAlfEnv;

class TAlfImage;

/**

 * Linear gradient brush. Draws a sequence of colors in a linear gradient.

 * A gradient brush can draw gradients in horizontal and vertical 

 * directions using any number of colors.

 * 

 * Usage:

 * @code

 * 

 * CAlfVisual* visual = CAlfVisual::AddNewL( control );

 * visual->EnableBrushesL();

 * CAlfGradientBrush* brush = CAlfGradientBrush::NewL( *iEnv );

 * 

 * // Configure the gradient: direction and colors.

 * brush->SetDirection( CAlfGradientBrush::EDirectionDown );

 * brush->SetColor( KRgbBlack, .5f );

 * brush->AppendColorL( 1, KRgbRed, 1.f );

 * brush->AppendColorL( 2, KRgbYellow, .1f );

 * 

 * //Append brush in brusharray with ownership to array 

 * visual->Brushes()->AppendL( brush, EAlfHasOwnership );

 * @endcode

 * @lib alfclient.lib

 * @since S60 v3.2

 */

NONSHARABLE_CLASS( CAlfGradientBrush ): public CAlfBrush

    {

public:

    /** Linear gradient directions. */

    enum TDirection

        {

        EDirectionUp,

        EDirectionRight,

        EDirectionDown,

        EDirectionLeft

        };

    /**

     * Constructor.

     */

    IMPORT_C static CAlfGradientBrush* NewL( CAlfEnv& aEnv );

    /**

     * Constructor. The new brush is left on the cleanup stack.

     */

    IMPORT_C static CAlfGradientBrush* NewLC( CAlfEnv& aEnv );

    /**

     * Destructor.

     */

    virtual ~CAlfGradientBrush();

    /**

     * Sets the gradient direction.

     */

    IMPORT_C void SetDirection(TDirection aDirection);

    /**

     * Replaces all colors with a single color.

     *

     * @param aColor    Solid color for the gradient.

     * @param aOpacity  Opacity.

     */

    IMPORT_C void SetColor(const TRgb& aColor, TReal32 aOpacity = 1.0) __SOFTFP;

    /**

     * Sets the image for the gradient. By default, no image is used. The image

     * can be cleared with <code>SetImage(TAlfImage())</code>.

     *

     * @param aImage  Image to use in the gradient.

     */

    IMPORT_C void SetImage(const TAlfImage& aImage);

    /**

     * Returns a color from the gradient.

     */

    IMPORT_C TRgb Color(TInt aIndex) const;

    /**

     * Returns an opacity value from the gradient.

     */

    IMPORT_C TReal32 Opacity(TInt aIndex) const;

    /**

     * Returns the image of the gradient brush.

     */

    IMPORT_C const TAlfImage& Image() const;

    /**

     * Appends a new color for the entire gradient. The caller must

     * append colors in the correct order, by ascending position.

     *

     * @param aPosition  Position of the color.

     * @param aColor     Color at the position.

     * @param aOpacity   Opacity at the position.

     */

    IMPORT_C void AppendColorL(

        TReal32 aPosition, 

        const TRgb& aColor,

        TReal32 aOpacity = 1.0) __SOFTFP;

private:

    CAlfGradientBrush();

    void ConstructL( CAlfEnv& aEnv );

private: // data

    struct TGradientBrushPrivateData;

    TGradientBrushPrivateData* iGradientBrushData;

    };

#endif // C_ALFGRADIENTBRUSH_H