Doc: Modularize QtOpenGL documentation.

This change moves the snippets to the modularized directories.

Change-Id: Ifcf22fa3f234681f851d1e7eed5fe44e2e223ffd
Reviewed-by: Marius Storm-Olsen <marius.storm-olsen@nokia.com>

1 files changed, 172 insertions, 0 deletions

diff --git a/src/opengl/doc/snippets/code/src_opengl_qgl.cpp b/src/opengl/doc/snippets/code/src_opengl_qgl.cpp
new file mode 100644
index 0000000000..4adc126159
--- /dev/null
+++ b/src/opengl/doc/snippets/code/src_opengl_qgl.cpp
@@ -0,0 +1,172 @@
+/****************************************************************************
+**
+** 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.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [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]