tabletcanvas.h Example File

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 #ifndef TABLETCANVAS_H
 #define TABLETCANVAS_H

 #include <QWidget>
 #include <QPixmap>
 #include <QPoint>
 #include <QTabletEvent>
 #include <QColor>
 #include <QBrush>
 #include <QPen>
 #include <QPoint>

 class QPaintEvent;
 class QString;

 class TabletCanvas : public QWidget
 {
     Q_OBJECT

 public:
     enum AlphaChannelType { AlphaPressure, AlphaTilt, NoAlpha };
     enum ColorSaturationType { SaturationVTilt, SaturationHTilt,
                                SaturationPressure, NoSaturation };
     enum LineWidthType { LineWidthPressure, LineWidthTilt, NoLineWidth };

     TabletCanvas();

     bool saveImage(const QString &file);
     bool loadImage(const QString &file);
     void setAlphaChannelType(AlphaChannelType type)
         { alphaChannelType = type; }
     void setColorSaturationType(ColorSaturationType type)
         { colorSaturationType = type; }
     void setLineWidthType(LineWidthType type)
         { lineWidthType = type; }
     void setColor(const QColor &color)
         { myColor = color; }
     QColor color() const
         { return myColor; }
     void setTabletDevice(QTabletEvent::TabletDevice device)
         { myTabletDevice = device; }
     int maximum(int a, int b)
         { return a > b ? a : b; }

 protected:
     void tabletEvent(QTabletEvent *event);
     void paintEvent(QPaintEvent *event);
     void resizeEvent(QResizeEvent *event);

 private:
     void initPixmap();
     void paintPixmap(QPainter &painter, QTabletEvent *event);
     Qt::BrushStyle brushPattern(qreal value);
     void updateBrush(QTabletEvent *event);

     AlphaChannelType alphaChannelType;
     ColorSaturationType colorSaturationType;
     LineWidthType lineWidthType;
     QTabletEvent::PointerType pointerType;
     QTabletEvent::TabletDevice myTabletDevice;
     QColor myColor;

     QPixmap pixmap;
     QBrush myBrush;
     QPen myPen;
     bool deviceDown;
     QPoint polyLine[3];
 };

 #endif