WTransferFunctionColorPoint.h

//---------------------------------------------------------------------------
//
// Project: OpenWalnut ( http://www.openwalnut.org )
//
// Copyright 2009 OpenWalnut Community, BSV@Uni-Leipzig and CNCF@MPI-CBS
// For more information see http://www.openwalnut.org/copying
//
// This file is part of OpenWalnut.
//
// OpenWalnut is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// OpenWalnut is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with OpenWalnut. If not, see <http://www.gnu.org/licenses/>.
//
//---------------------------------------------------------------------------
 
#ifndef WTRANSFERFUNCTIONCOLORPOINT_H
#define WTRANSFERFUNCTIONCOLORPOINT_H
 
#include <QGraphicsItem>
#include <QGraphicsObject>
 
#include "QMenu"
 
class WTransferFunctionWidget;
 
/**
 * A control point for the color function.
 *
 * Internals:
 * The point has links to its left and right neighbors (double-linked list).
 */
class WTransferFunctionColorPoint: public QGraphicsObject
{
    Q_OBJECT
 
public:
    /** type of our base class */
    typedef QGraphicsObject BaseClass;
 
    /**
     * Default constructor.
     *
     * \param parent the parent widget
     */
    explicit WTransferFunctionColorPoint( WTransferFunctionWidget* parent = 0x0 );
 
    /**
     * Default destructor
     */
    virtual ~WTransferFunctionColorPoint();
 
    /**
     * Returns the item left of the this item.
     *
     * \returns the item left of us
     */
    WTransferFunctionColorPoint *getLeft() const;
 
    /**
     * Returns the item right of this item.
     *
     * \returns the item right of us
     */
    WTransferFunctionColorPoint *getRight() const;
 
    /**
     * Set the item left of us.
     *
     * \param left the item left of us
     */
    void setLeft( WTransferFunctionColorPoint* left );
 
    /**
     * Set the item right of us.
     *
     * \param right the item right of us
     */
    void setRight( WTransferFunctionColorPoint* right );
 
    /**
     * The bounding rectangle used for paint and click events.
     *
     * \returns the bounding rectangle
     */
    QRectF boundingRect() const;
 
    /**
     * Paint the handle and additional item hints.
     *
     * \param painter the painter used
     * \param option the paint options used
     * \param widget the widget used for painting
     */
    virtual void paint( QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget* widget = 0x0 );
 
    /** \returns the color of the entry */
    QColor getColor() const;
 
    /**
     * Drag enter implementation for items that contain a color.
     *
     * \param event the event to handle
     */
    virtual void dragEnterEvent( QGraphicsSceneDragDropEvent* event );
 
    /**
     * Drop implementation for items that contain a color.
     *
     * \param event the event to handle
     */
    virtual void dropEvent( QGraphicsSceneDragDropEvent* event );
 
    /**
     * Handler for context menu envents. Currently disabled because it conflicts with other mouse interactions.
     *
     * \param event the event to hanlde
     */
    void contextMenuEvent( QGraphicsSceneContextMenuEvent* event );
 
public slots:
    /**
     * Called by the color dialog every time the user changes the color.
     *
     * \param color the new color
     */
    void colorSelected( const QColor& color );
 
protected:
    /**
     * Helper for item changed.
     *
     * \param rectangle a rectangle
     */
    void clampToRectangle( const QRectF& rectangle );
 
    /**
     * Helper for item changed.
     **/
    void clampToLeftAndRight();
 
    /**
     * Handles change notifications.
     *
     * \param change the requrested change
     * \param value the requested value
     * \returns the proposed value
     */
    QVariant itemChange( GraphicsItemChange change, const QVariant &value );
 
    /**
     * Handles mouse move events.
     *
     * \param event the event
     */
    void mouseMoveEvent( QGraphicsSceneMouseEvent *event );
 
    /**
     * Handles press move events.
     *
     * \param event the event
     */
    void mousePressEvent( QGraphicsSceneMouseEvent *event );
 
    /**
     * Handles mouse move events.
     *
     * \param event the event
     */
    void mouseReleaseEvent( QGraphicsSceneMouseEvent *event );
 
    /**
     * Handles mouse double click events by opening a color selector
     * if the item is clicked.
     *
     * \param event the event
     */
    void mouseDoubleClickEvent( QGraphicsSceneMouseEvent *event );
 
    /**
     * Show the color picker dialog.
     **/
    void showColorPicker();
 
private:
    /** the radius used for paining of the handle */
    double radius;
 
    /** the entry left of this entry */
    WTransferFunctionColorPoint *left;
 
    /** the entry to the right of our entry */
    WTransferFunctionColorPoint *right;
 
    /** the parent widget */
    WTransferFunctionWidget* _parent;
 
    /** the color entry */
    QColor color;
};
 
#endif  // WTRANSFERFUNCTIONCOLORPOINT_H