Qt 5.6 | Qt Widgets | Painter Paths Example | renderarea.cpp Example File

Qt 5.6.2 Reference Documentation

# renderarea.cpp Example File

painting/painterpaths/renderarea.cpp

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      #include "renderarea.h"

      #include <QPainter>

      RenderArea::RenderArea(const QPainterPath &path, QWidget *parent)
          : QWidget(parent), path(path)
      {
          penWidth = 1;
          rotationAngle = 0;
          setBackgroundRole(QPalette::Base);
      }

      QSize RenderArea::minimumSizeHint() const
      {
          return QSize(50, 50);
      }

      QSize RenderArea::sizeHint() const
      {
          return QSize(100, 100);
      }

      void RenderArea::setFillRule(Qt::FillRule rule)
      {
          path.setFillRule(rule);
          update();
      }

      void RenderArea::setFillGradient(const QColor &color1, const QColor &color2)
      {
          fillColor1 = color1;
          fillColor2 = color2;
          update();
      }

      void RenderArea::setPenWidth(int width)
      {
          penWidth = width;
          update();
      }

      void RenderArea::setPenColor(const QColor &color)
      {
          penColor = color;
          update();
      }

      void RenderArea::setRotationAngle(int degrees)
      {
          rotationAngle = degrees;
          update();
      }

      void RenderArea::paintEvent(QPaintEvent *)
      {
          QPainter painter(this);
          painter.setRenderHint(QPainter::Antialiasing);
          painter.scale(width() / 100.0, height() / 100.0);
          painter.translate(50.0, 50.0);
          painter.rotate(-rotationAngle);
          painter.translate(-50.0, -50.0);

          painter.setPen(QPen(penColor, penWidth, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));
          QLinearGradient gradient(0, 0, 0, 100);
          gradient.setColorAt(0.0, fillColor1);
          gradient.setColorAt(1.0, fillColor2);
          painter.setBrush(gradient);
          painter.drawPath(path);
      }