shadewidget.h

#ifndef SHADEWIDGET_H
#define SHADEWIDGET_H

#include <QtGui>
#include "Volume.h"

class HoverPoints;

class ShadeWidget : public QWidget
{
    Q_OBJECT
public:
    enum ShadeType {
        RedShade,
        GreenShade,
        BlueShade,
        ARGBShade
    };

    ShadeWidget(ShadeType type, QWidget *parent);
        
        void setHistogramPtr(QPixmap *histogramPtr);
    void setGradientStops(const QGradientStops &stops);

    void paintEvent(QPaintEvent *e);
        
    QSize sizeHint() const;
    QPolygonF points() const;
    HoverPoints *hoverPoints() const { return m_hoverPoints; }

    uint colorAt(int x);

signals:
    void colorsChanged();

private:
    void generateShade();

    ShadeType m_shade_type;
    QImage m_shade;
    HoverPoints *m_hoverPoints;
    QLinearGradient m_alpha_gradient;
    QPixmap *m_histogram;
};

#endif // SHADEWIDGET_H

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