openglwindow.cpp Example File

openglwindow/openglwindow.cpp
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#include "openglwindow.h" #include <QtCore/QCoreApplication> #include <QtGui/QOpenGLContext> #include <QtGui/QOpenGLPaintDevice> #include <QtGui/QPainter> OpenGLWindow::OpenGLWindow(QWindow *parent) : QWindow(parent) , m_animating(false) , m_context(0) , m_device(0) { setSurfaceType(QWindow::OpenGLSurface); } OpenGLWindow::~OpenGLWindow() { delete m_device; } void OpenGLWindow::render(QPainter *painter) { Q_UNUSED(painter); } void OpenGLWindow::initialize() { } void OpenGLWindow::render() { if (!m_device) m_device = new QOpenGLPaintDevice; glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); m_device->setSize(size() * devicePixelRatio()); m_device->setDevicePixelRatio(devicePixelRatio()); QPainter painter(m_device); render(&painter); } void OpenGLWindow::renderLater() { requestUpdate(); } bool OpenGLWindow::event(QEvent *event) { switch (event->type()) { case QEvent::UpdateRequest: renderNow(); return true; default: return QWindow::event(event); } } void OpenGLWindow::exposeEvent(QExposeEvent *event) { Q_UNUSED(event); if (isExposed()) renderNow(); } void OpenGLWindow::renderNow() { if (!isExposed()) return; bool needsInitialize = false; if (!m_context) { m_context = new QOpenGLContext(this); m_context->setFormat(requestedFormat()); m_context->create(); needsInitialize = true; } m_context->makeCurrent(this); if (needsInitialize) { initializeOpenGLFunctions(); initialize(); } render(); m_context->swapBuffers(this); if (m_animating) renderLater(); } void OpenGLWindow::setAnimating(bool animating) { m_animating = animating; if (animating) renderLater(); }