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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
//! [0]
QGLFormat fmt;
fmt.setAlpha(true);
fmt.setStereo(true);
QGLFormat::setDefaultFormat(fmt);
//! [0]
//! [1]
QGLFormat fmt;
fmt.setDoubleBuffer(false); // single buffer
fmt.setDirectRendering(false); // software rendering
MyGLWidget* myWidget = new MyGLWidget(fmt, ...);
//! [1]
//! [2]
QGLFormat fmt;
fmt.setOverlay(true);
fmt.setStereo(true);
MyGLWidget* myWidget = new MyGLWidget(fmt, ...);
if (!myWidget->format().stereo()) {
// ok, goggles off
if (!myWidget->format().hasOverlay()) {
qFatal("Cool hardware required");
}
}
//! [2]
//! [3]
// The rendering in MyGLWidget depends on using
// stencil buffer and alpha channel
MyGLWidget::MyGLWidget(QWidget* parent)
: QGLWidget(QGLFormat(QGL::StencilBuffer | QGL::AlphaChannel), parent)
{
if (!format().stencil())
qWarning("Could not get stencil buffer; results will be suboptimal");
if (!format().alpha())
qWarning("Could not get alpha channel; results will be suboptimal");
...
}
//! [3]
//! [4]
QApplication a(argc, argv);
QGLFormat f;
f.setDoubleBuffer(false);
QGLFormat::setDefaultFormat(f);
//! [4]
//! [5]
QGLFormat f = QGLFormat::defaultOverlayFormat();
f.setDoubleBuffer(true);
QGLFormat::setDefaultOverlayFormat(f);
//! [5]
//! [6]
// ...continued from above
MyGLWidget* myWidget = new MyGLWidget(QGLFormat(QGL::HasOverlay), ...);
if (myWidget->format().hasOverlay()) {
// Yes, we got an overlay, let's check _its_ format:
QGLContext* olContext = myWidget->overlayContext();
if (olContext->format().doubleBuffer())
; // yes, we got a double buffered overlay
else
; // no, only single buffered overlays are available
}
//! [6]
//! [7]
QGLContext *cx;
// ...
QGLFormat f;
f.setStereo(true);
cx->setFormat(f);
if (!cx->create())
exit(); // no OpenGL support, or cannot render on the specified paintdevice
if (!cx->format().stereo())
exit(); // could not create stereo context
//! [7]
//! [8]
class MyGLDrawer : public QGLWidget
{
Q_OBJECT // must include this if you use Qt signals/slots
public:
MyGLDrawer(QWidget *parent)
: QGLWidget(parent) {}
protected:
void initializeGL()
{
// Set up the rendering context, define display lists etc.:
...
glClearColor(0.0, 0.0, 0.0, 0.0);
glEnable(GL_DEPTH_TEST);
...
}
void resizeGL(int w, int h)
{
// setup viewport, projection etc.:
glViewport(0, 0, (GLint)w, (GLint)h);
...
glFrustum(...);
...
}
void paintGL()
{
// draw the scene:
...
glRotatef(...);
glMaterialfv(...);
glBegin(GL_QUADS);
glVertex3f(...);
glVertex3f(...);
...
glEnd();
...
}
};
//! [8]
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