qt5base-lts/examples/gui/openglwindow/openglwindow.cpp
Samuel Rødal f3b45ffa61 Added OpenGL example and documentation.
Change-Id: I2d9d4e52caf0a39fef9648d8a9e83a0c1328f650
Reviewed-by: Paul Olav Tvete <paul.tvete@nokia.com>
2012-08-29 16:53:00 +02:00

170 lines
4.1 KiB
C++

/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
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** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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****************************************************************************/
#include "openglwindow.h"
#include <QtCore/QCoreApplication>
#include <QtGui/QOpenGLContext>
#include <QtGui/QOpenGLPaintDevice>
#include <QtGui/QPainter>
//! [1]
OpenGLWindow::OpenGLWindow(QWindow *parent)
: QWindow(parent)
, m_update_pending(false)
, m_animating(false)
, m_context(0)
, m_device(0)
{
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());
QPainter painter(m_device);
render(&painter);
}
//! [2]
//! [3]
void OpenGLWindow::renderLater()
{
if (!m_update_pending) {
m_update_pending = true;
QCoreApplication::postEvent(this, new QEvent(QEvent::UpdateRequest));
}
}
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::resizeEvent(QResizeEvent *event)
{
Q_UNUSED(event);
if (isExposed())
renderNow();
}
//! [3]
//! [4]
void OpenGLWindow::renderNow()
{
if (!isExposed())
return;
m_update_pending = false;
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]