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# tabletcanvas.h Example File

widgets/tablet/tabletcanvas.h

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
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     ** modification, are permitted provided that the following conditions are
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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