rasterwindow.cpp Example File

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#include "rasterwindow.h" RasterWindow::RasterWindow(const QSafeSize &size, QWindow *parent) :QWindow(parent) ,AbstractWindow(size) ,m_buffer(size) { create(); resize(size.width(), size.height()); QSurfaceFormat fmt = format(); fmt.setAlphaBufferSize(8); setFormat(fmt); m_backingStore = new QBackingStore(this); } bool RasterWindow::event(QEvent *event) { if (event->type() == QEvent::UpdateRequest) { renderNow(); return true; } return QWindow::event(event); } void RasterWindow::renderLater() { requestUpdate(); } void RasterWindow::resizeEvent(QResizeEvent *resizeEvent) { m_backingStore->resize(resizeEvent->size()); renderNow(); } void RasterWindow::exposeEvent(QExposeEvent *) { renderNow(); } void RasterWindow::render() { renderNow(); } void RasterWindow::renderNow() { if (!isExposed()) return; QRect rect(0, 0, width(), height()); m_backingStore->beginPaint(rect); QPaintDevice *device = m_backingStore->paintDevice(); QPainter painter(device); painter.fillRect(0, 0, width(), height(), Qt::black); render(&painter); m_backingStore->endPaint(); m_backingStore->flush(rect); } void RasterWindow::render(QPainter *painter) { QRect rect(0, 0, width(), height()); painter->drawImage(rect, m_buffer.image()); }

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