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     7 ** This file is part of the examples of the Qt Toolkit.

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    40 ****************************************************************************/

    41 

    42 

    43 #include "interfaces.h"

    44 #include "paintarea.h"

    45 

    46 #include <QPainter>

    47 #include <QMouseEvent>

    48 

    49 PaintArea::PaintArea(QWidget *parent) :

    50     QWidget(parent),

    51     theImage(500, 400, QImage::Format_RGB32),

    52     color(Qt::blue),

    53     thickness(3),

    54     brushInterface(0),

    55     lastPos(-1, -1)

    56 {

    57     setAttribute(Qt::WA_StaticContents);

    58     setAttribute(Qt::WA_NoBackground);

    59 

    60     theImage.fill(qRgb(255, 255, 255));

    61 }

    62 

    63 bool PaintArea::openImage(const QString &fileName)

    64 {

    65     QImage image;

    66     if (!image.load(fileName))

    67         return false;

    68 

    69     setImage(image);

    70     return true;

    71 }

    72 

    73 bool PaintArea::saveImage(const QString &fileName, const char *fileFormat)

    74 {

    75     return theImage.save(fileName, fileFormat);

    76 }

    77 

    78 void PaintArea::setImage(const QImage &image)

    79 {

    80     theImage = image.convertToFormat(QImage::Format_RGB32);

    81     update();

    82     updateGeometry();

    83 }

    84 

    85 void PaintArea::insertShape(const QPainterPath &path)

    86 {

    87     pendingPath = path;

    88 #ifndef QT_NO_CURSOR

    89     setCursor(Qt::CrossCursor);

    90 #endif

    91 }

    92 

    93 void PaintArea::setBrushColor(const QColor &color)

    94 {

    95     this->color = color;

    96 }

    97 

    98 void PaintArea::setBrushWidth(int width)

    99 {

   100     thickness = width;

   101 }

   102 

   103 //! [0]

   104 void PaintArea::setBrush(BrushInterface *brushInterface, const QString &brush)

   105 {

   106     this->brushInterface = brushInterface;

   107     this->brush = brush;

   108 }

   109 //! [0]

   110 

   111 QSize PaintArea::sizeHint() const

   112 {

   113     return theImage.size();

   114 }

   115 

   116 void PaintArea::paintEvent(QPaintEvent * /* event */)

   117 {

   118     QPainter painter(this);

   119     painter.drawImage(QPoint(0, 0), theImage);

   120 }

   121 

   122 void PaintArea::mousePressEvent(QMouseEvent *event)

   123 {

   124     if (event->button() == Qt::LeftButton) {

   125         if (!pendingPath.isEmpty()) {

   126             QPainter painter(&theImage);

   127             setupPainter(painter);

   128 

   129             const QRectF boundingRect = pendingPath.boundingRect();

   130             QLinearGradient gradient(boundingRect.topRight(),

   131                                      boundingRect.bottomLeft());

   132             gradient.setColorAt(0.0, QColor(color.red(), color.green(),

   133                                             color.blue(), 63));

   134             gradient.setColorAt(1.0, QColor(color.red(), color.green(),

   135                                             color.blue(), 191));

   136             painter.setBrush(gradient);

   137             painter.translate(event->pos() - boundingRect.center());

   138             painter.drawPath(pendingPath);

   139 

   140             pendingPath = QPainterPath();

   141 #ifndef QT_NO_CURSOR

   142             unsetCursor();

   143 #endif

   144             update();

   145         } else {

   146             if (brushInterface) {

   147                 QPainter painter(&theImage);

   148                 setupPainter(painter);

   149                 const QRect rect = brushInterface->mousePress(brush, painter,

   150                                                               event->pos());

   151                 update(rect);

   152             }

   153 

   154             lastPos = event->pos();

   155         }

   156     }

   157 }

   158 

   159 //! [1]

   160 void PaintArea::mouseMoveEvent(QMouseEvent *event)

   161 {

   162     if ((event->buttons() & Qt::LeftButton) && lastPos != QPoint(-1, -1)) {

   163         if (brushInterface) {

   164             QPainter painter(&theImage);

   165             setupPainter(painter);

   166             const QRect rect = brushInterface->mouseMove(brush, painter, lastPos,

   167                                                          event->pos());

   168             update(rect);

   169         }

   170 

   171         lastPos = event->pos();

   172     }

   173 }

   174 //! [1]

   175 

   176 void PaintArea::mouseReleaseEvent(QMouseEvent *event)

   177 {

   178     if (event->button() == Qt::LeftButton && lastPos != QPoint(-1, -1)) {

   179         if (brushInterface) {

   180             QPainter painter(&theImage);

   181             setupPainter(painter);

   182             QRect rect = brushInterface->mouseRelease(brush, painter,

   183                                                       event->pos());

   184             update(rect);

   185         }

   186 

   187         lastPos = QPoint(-1, -1);

   188     }

   189 }

   190 

   191 void PaintArea::setupPainter(QPainter &painter)

   192 {

   193     painter.setRenderHint(QPainter::Antialiasing, true);

   194     painter.setPen(QPen(color, thickness, Qt::SolidLine, Qt::RoundCap,

   195                    Qt::RoundJoin));

   196 }