/*

* 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:   Defines CHuiLinearGradientBrush - a Brush that is able to 

*                draw linear color gradients.

*

*/

#ifndef __HUIGRADIENTBRUSH_H__

#define __HUIGRADIENTBRUSH_H__

#include <e32base.h>

#include <uiacceltk/HuiBrush.h>

#include <uiacceltk/HuiSkin.h>

#include <uiacceltk/HuiGc.h>

#include <uiacceltk/HuiImage.h>

/**

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

 */

NONSHARABLE_CLASS(CHuiGradientBrush) : public CHuiBrush

    {

public:

    /** Linear gradient directions. */

    enum TDirection

        {

        EDirectionUp,

        EDirectionRight,

        EDirectionDown,

        EDirectionLeft

        };

    /* Constructors and destructor. */

    /**

     * Constructor.

     */

    IMPORT_C static CHuiGradientBrush* NewL();

    /**

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

     */

    IMPORT_C static CHuiGradientBrush* NewLC();

    /**

     * Destructor.

     */

    ~CHuiGradientBrush();

    /* Methods. */

    /**

     * 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 virtual 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(THuiImage())</code>.

     *

     * @param aImage  Image to use in the gradient.

     */

    IMPORT_C virtual void SetImage(const THuiImage& aImage);

    /**

     * Returns a color from the gradient.

     */

    IMPORT_C virtual TRgb Color(TInt aIndex) const;

    /**

     * Returns an opacity value from the gradient.

     */

    IMPORT_C virtual TReal32 Opacity(TInt aIndex) const __SOFTFP;

    /**

     * Returns the image of the gradient brush.

     */

    IMPORT_C virtual const THuiImage& 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 virtual void AppendColorL(TReal32 aPosition, const TRgb& aColor,

                                       TReal32 aOpacity = 1.0) __SOFTFP;

    /**

     * Draw the brush.

     */

    virtual void Draw(CHuiGc& aGc, const MHuiBrushGuide& aGuide) const;

protected:

    /* Constructors. */

    /**

     * Constructor.

     */

    CHuiGradientBrush();

    /**

     * Second-phase constructor.

     */

    void ConstructL();

private:

    /* Private data */

    /** One color in the gradient. */

    struct SColor

        {

        /** Position in the range 0..1. */

        TReal32 iPosition;

        /** RGB color. */

        TRgb iColor;

        /** Opacity. */

        TReal32 iOpacity;

        };

private:

    /* Private methods */

private:

    /** Direction of a linear gradient. */

    TDirection iDirection;

    /** Array of gradient colors. */

    RArray<SColor> iColors;

    /** Image for the gradient. */

    THuiImage iImage;

    };

#endif  // __HUIGRADIENTBRUSH_H__