/*

* 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 CHuiLineVisual, Visual that is able to draw lines 

*                onto a curve path. 

*

*/

#ifndef __HUILINEVISUAL_H__

#define __HUILINEVISUAL_H__

#include <e32base.h>

#include <uiacceltk/HuiVisual.h>

#include <uiacceltk/HuiImage.h>

#include <uiacceltk/HuiOwnedPointer.h>

#include <uiacceltk/HuiCurvePath.h>

#include <uiacceltk/HuiGc.h>

#include <uiacceltk/HuiMappingFunctions.h>

/* Forward declarations */

class CHuiEnv;

class CHuiControl;

/**

 * Line visual draws a line along a curve path.

 *

 * A line visual will draw a bendy line that follows a specified

 * curve path. Width and alpha functions can be set to change the

 * opacity and thickness of the line along its length.

 *

 * Note that the Bitgdi renderer contains only a minimal implementation

 * of line drawing. There is no aliasing or shading on the line, and

 * thickness and alpha functions have no effect. The entire thickness of a Bitgdi

 * line is set by the initial thickness at point 0.

 *

 * @see CHuiCurvePath

 */

NONSHARABLE_CLASS(CHuiLineVisual) : public CHuiVisual

    {

public:

    /* Constructors and destructor. */

    /**

     * Constructs and appends a new text visual to the owner control.

     *

     * @param aOwnerControl  Control that will own the new visual.

     *

     * @return  The new visual.

     */

    IMPORT_C static CHuiLineVisual* AddNewL(CHuiControl& aOwnerControl,

                                            CHuiLayout* aParentLayout);

    /**

     * Constructor.

     */

    CHuiLineVisual(MHuiVisualOwner& aOwner);

    /**

     * Second-phase constructor.

     */

    void ConstructL();

    /**

     * Destructor.

     */

    virtual ~CHuiLineVisual();

    /* Methods. */

    /**

     * Sets the path instance of the visual.

     *

     * @param aPath

     * @param aOwnership

     */

    IMPORT_C void SetPath(CHuiCurvePath* aPath, THuiOwnership aOwnership);

    /**

     * Returns the path of the visual. The path can be modified via this

     * reference.

     */

    IMPORT_C CHuiCurvePath& Path();

    virtual TBool Changed() const;

    virtual void ClearChanged();

    /**

     * Sets the image used by the line.

     */

    IMPORT_C void SetImage(const THuiImage& aImage);

    /**

     * Sets the alpha mapping function that generates alpha values for the

     * path.

     */

    IMPORT_C void SetAlphaFunction(MHuiMappingFunction* aFunction);

    /**

     * Sets the width mapping function that generates width values for the

     * path.

     */

    IMPORT_C void SetWidthFunction(MHuiMappingFunction* aFunction);

     /**

     * Sets the color of the line.

     *

     * @param aColor           Line color.

     */

    IMPORT_C void SetColor(const TRgb& aColor);

    /**

     * Draw the curve path.

     */

    virtual void DrawSelf(CHuiGc& aGc, const TRect& aDisplayRect) const;

    /**

     * Expand dirty region

     */

    void ExpandRectWithContent(TRect& aRect) const;

private:

    /* Private methods */

private:

    /** The path of the visual. */

    RHuiOwnedPointer<CHuiCurvePath> iPath;

    /** Image used by the line. */

    THuiImage iImage;

    /** Value mapping function that generates alpha values for path

        positions. */

    MHuiMappingFunction* iAlphaFunction;

    /** Custom width mapping function. */

    MHuiMappingFunction* iWidthFunction;

    /** Determines the width of the line. Depends on the current value

        of iThickness. */

    mutable THuiConstantMappingFunction iDefaultWidthFunction;

public:

    /* Public properties. */

    /** Thickness of the line. */

    THuiTimedValue iThickness;

    /** Thickness of the shadow around the line. */

    THuiTimedValue iShadowThickness;

    /** Current start position on the path. */

    THuiTimedValue iStartPos;

    /** Current end position on the path. */

    THuiTimedValue iEndPos;

private:

    /** Line color */

    TRgb iColor;

    };

#endif  // __HUILINEVISUAL_H__