qt5base-lts/examples/gui/openglwindow/openglwindow.cpp
Christian Ehrlicher b0042601ed Cleanup QtOpenGL examples
Cleanup the OpenGL examples
 - use nullptr (clang-tidy)
 - use member-initialization
 - avoid redundant checks for != nullptr when deleting a pointer

Change-Id: I3e4702690ed79e71c3e952d51ceef83b907b45b7
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>
2019-09-30 22:16:27 +02:00

162 lines
4.2 KiB
C++

/****************************************************************************
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#include "openglwindow.h"
#include <QOpenGLContext>
#include <QOpenGLPaintDevice>
#include <QPainter>
//! [1]
OpenGLWindow::OpenGLWindow(QWindow *parent)
: QWindow(parent)
{
setSurfaceType(QWindow::OpenGLSurface);
}
//! [1]
OpenGLWindow::~OpenGLWindow()
{
delete m_device;
}
//! [2]
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);
}
//! [2]
//! [3]
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();
}
//! [3]
//! [4]
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();
}
//! [4]
//! [5]
void OpenGLWindow::setAnimating(bool animating)
{
m_animating = animating;
if (animating)
renderLater();
}
//! [5]