remove display lists and qt3d-ize overpainting/hellogl example

On the way to making opengl examples portable, remove display lists
and go to triangles only. Use QMatrix4x4. While on the job use Qt/3D
stylee to make the QtLogo as an example of 3D programming more Qt-like.

Reviewed-by: Rhys Weatherley

8 files changed, 549 insertions, 231 deletions

diff --git a/examples/opengl/hellogl/glwidget.cpp b/examples/opengl/hellogl/glwidget.cpp
index 64e14ea..b0c3ba4 100644
--- a/examples/opengl/hellogl/glwidget.cpp
+++ b/examples/opengl/hellogl/glwidget.cpp
@@ -45,12 +45,13 @@
 #include <math.h>
 
 #include "glwidget.h"
+#include "qtlogo.h"
 
 //! [0]
 GLWidget::GLWidget(QWidget *parent)
     : QGLWidget(parent)
 {
-    object = 0;
+    logo = 0;
     xRot = 0;
     yRot = 0;
     zRot = 0;
@@ -63,8 +64,6 @@ GLWidget::GLWidget(QWidget *parent)
 //! [1]
 GLWidget::~GLWidget()
 {
-    makeCurrent();
-    glDeleteLists(object, 1);
 }
 //! [1]
 
@@ -83,10 +82,18 @@ QSize GLWidget::sizeHint() const
 }
 //! [4]
 
+static void qNormalizeAngle(int &angle)
+{
+    while (angle < 0)
+        angle += 360 * 16;
+    while (angle > 360 * 16)
+        angle -= 360 * 16;
+}
+
 //! [5]
 void GLWidget::setXRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != xRot) {
         xRot = angle;
         emit xRotationChanged(angle);
@@ -97,7 +104,7 @@ void GLWidget::setXRotation(int angle)
 
 void GLWidget::setYRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != yRot) {
         yRot = angle;
         emit yRotationChanged(angle);
@@ -107,7 +114,7 @@ void GLWidget::setYRotation(int angle)
 
 void GLWidget::setZRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != zRot) {
         zRot = angle;
         emit zRotationChanged(angle);
@@ -119,10 +126,18 @@ void GLWidget::setZRotation(int angle)
 void GLWidget::initializeGL()
 {
     qglClearColor(qtPurple.dark());
-    object = makeObject();
-    glShadeModel(GL_FLAT);
+
+    logo = new QtLogo(this, 64);
+    logo->setColor(qtGreen.dark());
+
     glEnable(GL_DEPTH_TEST);
     glEnable(GL_CULL_FACE);
+    glShadeModel(GL_SMOOTH);
+    glEnable(GL_LIGHTING);
+    glEnable(GL_LIGHT0);
+    glEnable(GL_MULTISAMPLE);
+    static GLfloat lightPosition[4] = { 0.5, 5.0, 7.0, 1.0 };
+    glLightfv(GL_LIGHT0, GL_POSITION, lightPosition);
 }
 //! [6]
 
@@ -135,7 +150,7 @@ void GLWidget::paintGL()
     glRotated(xRot / 16.0, 1.0, 0.0, 0.0);
     glRotated(yRot / 16.0, 0.0, 1.0, 0.0);
     glRotated(zRot / 16.0, 0.0, 0.0, 1.0);
-    glCallList(object);
+    logo->draw();
 }
 //! [7]
 
@@ -147,7 +162,7 @@ void GLWidget::resizeGL(int width, int height)
 
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
-    glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0);
+    glOrtho(-0.5, +0.5, -0.5, +0.5, 4.0, 15.0);
     glMatrixMode(GL_MODELVIEW);
 }
 //! [8]
@@ -175,92 +190,3 @@ void GLWidget::mouseMoveEvent(QMouseEvent *event)
     lastPos = event->pos();
 }
 //! [10]
-
-GLuint GLWidget::makeObject()
-{
-    GLuint list = glGenLists(1);
-    glNewList(list, GL_COMPILE);
-
-    glBegin(GL_QUADS);
-
-    GLdouble x1 = +0.06;
-    GLdouble y1 = -0.14;
-    GLdouble x2 = +0.14;
-    GLdouble y2 = -0.06;
-    GLdouble x3 = +0.08;
-    GLdouble y3 = +0.00;
-    GLdouble x4 = +0.30;
-    GLdouble y4 = +0.22;
-
-    quad(x1, y1, x2, y2, y2, x2, y1, x1);
-    quad(x3, y3, x4, y4, y4, x4, y3, x3);
-
-    extrude(x1, y1, x2, y2);
-    extrude(x2, y2, y2, x2);
-    extrude(y2, x2, y1, x1);
-    extrude(y1, x1, x1, y1);
-    extrude(x3, y3, x4, y4);
-    extrude(x4, y4, y4, x4);
-    extrude(y4, x4, y3, x3);
-
-    const double Pi = 3.14159265358979323846;
-    const int NumSectors = 200;
-
-    for (int i = 0; i < NumSectors; ++i) {
-        double angle1 = (i * 2 * Pi) / NumSectors;
-        GLdouble x5 = 0.30 * sin(angle1);
-        GLdouble y5 = 0.30 * cos(angle1);
-        GLdouble x6 = 0.20 * sin(angle1);
-        GLdouble y6 = 0.20 * cos(angle1);
-
-        double angle2 = ((i + 1) * 2 * Pi) / NumSectors;
-        GLdouble x7 = 0.20 * sin(angle2);
-        GLdouble y7 = 0.20 * cos(angle2);
-        GLdouble x8 = 0.30 * sin(angle2);
-        GLdouble y8 = 0.30 * cos(angle2);
-
-        quad(x5, y5, x6, y6, x7, y7, x8, y8);
-
-        extrude(x6, y6, x7, y7);
-        extrude(x8, y8, x5, y5);
-    }
-
-    glEnd();
-
-    glEndList();
-    return list;
-}
-
-void GLWidget::quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
-                    GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4)
-{
-    qglColor(qtGreen);
-
-    glVertex3d(x1, y1, -0.05);
-    glVertex3d(x2, y2, -0.05);
-    glVertex3d(x3, y3, -0.05);
-    glVertex3d(x4, y4, -0.05);
-
-    glVertex3d(x4, y4, +0.05);
-    glVertex3d(x3, y3, +0.05);
-    glVertex3d(x2, y2, +0.05);
-    glVertex3d(x1, y1, +0.05);
-}
-
-void GLWidget::extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2)
-{
-    qglColor(qtGreen.dark(250 + int(100 * x1)));
-
-    glVertex3d(x1, y1, +0.05);
-    glVertex3d(x2, y2, +0.05);
-    glVertex3d(x2, y2, -0.05);
-    glVertex3d(x1, y1, -0.05);
-}
-
-void GLWidget::normalizeAngle(int *angle)
-{
-    while (*angle < 0)
-        *angle += 360 * 16;
-    while (*angle > 360 * 16)
-        *angle -= 360 * 16;
-}
diff --git a/examples/opengl/hellogl/glwidget.h b/examples/opengl/hellogl/glwidget.h
index b202a61..4ffd4d7 100644
--- a/examples/opengl/hellogl/glwidget.h
+++ b/examples/opengl/hellogl/glwidget.h
@@ -44,6 +44,8 @@
 
 #include <QGLWidget>
 
+class QtLogo;
+
 //! [0]
 class GLWidget : public QGLWidget
 {
@@ -80,13 +82,7 @@ protected:
 
 //! [3]
 private:
-    GLuint makeObject();
-    void quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
-              GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4);
-    void extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2);
-    void normalizeAngle(int *angle);
-
-    GLuint object;
+    QtLogo *logo;
     int xRot;
     int yRot;
     int zRot;
diff --git a/examples/opengl/hellogl/hellogl.pro b/examples/opengl/hellogl/hellogl.pro
index 6d57c19..0e3209a 100644
--- a/examples/opengl/hellogl/hellogl.pro
+++ b/examples/opengl/hellogl/hellogl.pro
@@ -1,8 +1,13 @@
+VPATH += ../shared
+INCLUDEPATH += ../shared
+
 HEADERS       = glwidget.h \
-                window.h
+                window.h \
+                qtlogo.h
 SOURCES       = glwidget.cpp \
                 main.cpp \
-                window.cpp
+                window.cpp \
+                qtlogo.cpp
 QT           += opengl
 
 # install
diff --git a/examples/opengl/overpainting/glwidget.cpp b/examples/opengl/overpainting/glwidget.cpp
index 30d3266..0dcccbf 100644
--- a/examples/opengl/overpainting/glwidget.cpp
+++ b/examples/opengl/overpainting/glwidget.cpp
@@ -46,6 +46,7 @@
 #include <math.h>
 
 #include "bubble.h"
+#include "qtlogo.h"
 #include "glwidget.h"
 
 #ifndef GL_MULTISAMPLE
@@ -59,7 +60,7 @@ GLWidget::GLWidget(QWidget *parent)
     QTime midnight(0, 0, 0);
     qsrand(midnight.secsTo(QTime::currentTime()));
 
-    object = 0;
+    logo = 0;
     xRot = 0;
     yRot = 0;
     zRot = 0;
@@ -80,28 +81,34 @@ GLWidget::GLWidget(QWidget *parent)
 //! [1]
 GLWidget::~GLWidget()
 {
-    makeCurrent();
-    glDeleteLists(object, 1);
 }
 //! [1]
 
+static void qNormalizeAngle(int &angle)
+{
+    while (angle < 0)
+        angle += 360 * 16;
+    while (angle > 360 * 16)
+        angle -= 360 * 16;
+}
+
 void GLWidget::setXRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != xRot)
         xRot = angle;
 }
 
 void GLWidget::setYRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != yRot)
         yRot = angle;
 }
 
 void GLWidget::setZRotation(int angle)
 {
-    normalizeAngle(&angle);
+    qNormalizeAngle(angle);
     if (angle != zRot)
         zRot = angle;
 }
@@ -109,7 +116,10 @@ void GLWidget::setZRotation(int angle)
 //! [2]
 void GLWidget::initializeGL()
 {
-    object = makeObject();
+    glEnable(GL_MULTISAMPLE);
+
+    logo = new QtLogo(this);
+    logo->setColor(qtGreen.dark());
 }
 //! [2]
 
@@ -162,7 +172,8 @@ void GLWidget::paintEvent(QPaintEvent *event)
     glRotated(xRot / 16.0, 1.0, 0.0, 0.0);
     glRotated(yRot / 16.0, 0.0, 1.0, 0.0);
     glRotated(zRot / 16.0, 0.0, 0.0, 1.0);
-    glCallList(object);
+
+    logo->draw();
 //! [7]
 
 //! [8]
@@ -207,102 +218,6 @@ QSize GLWidget::sizeHint() const
     return QSize(400, 400);
 }
 
-GLuint GLWidget::makeObject()
-{
-    GLuint list = glGenLists(1);
-    glNewList(list, GL_COMPILE);
-
-    glEnable(GL_NORMALIZE);
-    glBegin(GL_QUADS);
-
-    static GLfloat logoDiffuseColor[4] = {qtGreen.red()/255.0,
-                                          qtGreen.green()/255.0,
-                                          qtGreen.blue()/255.0, 1.0};
-    glMaterialfv(GL_FRONT, GL_DIFFUSE, logoDiffuseColor);
-
-    GLdouble x1 = +0.06;
-    GLdouble y1 = -0.14;
-    GLdouble x2 = +0.14;
-    GLdouble y2 = -0.06;
-    GLdouble x3 = +0.08;
-    GLdouble y3 = +0.00;
-    GLdouble x4 = +0.30;
-    GLdouble y4 = +0.22;
-
-    quad(x1, y1, x2, y2, y2, x2, y1, x1);
-    quad(x3, y3, x4, y4, y4, x4, y3, x3);
-
-    extrude(x1, y1, x2, y2);
-    extrude(x2, y2, y2, x2);
-    extrude(y2, x2, y1, x1);
-    extrude(y1, x1, x1, y1);
-    extrude(x3, y3, x4, y4);
-    extrude(x4, y4, y4, x4);
-    extrude(y4, x4, y3, x3);
-
-    const double Pi = 3.14159265358979323846;
-    const int NumSectors = 200;
-
-    for (int i = 0; i < NumSectors; ++i) {
-        double angle1 = (i * 2 * Pi) / NumSectors;
-        GLdouble x5 = 0.30 * sin(angle1);
-        GLdouble y5 = 0.30 * cos(angle1);
-        GLdouble x6 = 0.20 * sin(angle1);
-        GLdouble y6 = 0.20 * cos(angle1);
-
-        double angle2 = ((i + 1) * 2 * Pi) / NumSectors;
-        GLdouble x7 = 0.20 * sin(angle2);
-        GLdouble y7 = 0.20 * cos(angle2);
-        GLdouble x8 = 0.30 * sin(angle2);
-        GLdouble y8 = 0.30 * cos(angle2);
-
-        quad(x5, y5, x6, y6, x7, y7, x8, y8);
-
-        extrude(x6, y6, x7, y7);
-        extrude(x8, y8, x5, y5);
-    }
-
-    glEnd();
-
-    glEndList();
-    return list;
-}
-
-void GLWidget::quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
-                    GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4)
-{
-    glNormal3d(0.0, 0.0, -1.0);
-    glVertex3d(x1, y1, -0.05);
-    glVertex3d(x2, y2, -0.05);
-    glVertex3d(x3, y3, -0.05);
-    glVertex3d(x4, y4, -0.05);
-
-    glNormal3d(0.0, 0.0, 1.0);
-    glVertex3d(x4, y4, +0.05);
-    glVertex3d(x3, y3, +0.05);
-    glVertex3d(x2, y2, +0.05);
-    glVertex3d(x1, y1, +0.05);
-}
-
-void GLWidget::extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2)
-{
-    qglColor(qtGreen.dark(250 + int(100 * x1)));
-
-    glNormal3d((x1 + x2)/2.0, (y1 + y2)/2.0, 0.0);
-    glVertex3d(x1, y1, +0.05);
-    glVertex3d(x2, y2, +0.05);
-    glVertex3d(x2, y2, -0.05);
-    glVertex3d(x1, y1, -0.05);
-}
-
-void GLWidget::normalizeAngle(int *angle)
-{
-    while (*angle < 0)
-        *angle += 360 * 16;
-    while (*angle > 360 * 16)
-        *angle -= 360 * 16;
-}
-
 void GLWidget::createBubbles(int number)
 {
     for (int i = 0; i < number; ++i) {
@@ -337,7 +252,7 @@ void GLWidget::setupViewport(int width, int height)
 
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
-    glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0);
+    glOrtho(-0.5, +0.5, -0.5, 0.5, 4.0, 15.0);
     glMatrixMode(GL_MODELVIEW);
 }
 //! [14]
diff --git a/examples/opengl/overpainting/glwidget.h b/examples/opengl/overpainting/glwidget.h
index 5323a6f..6c9f7e0 100644
--- a/examples/opengl/overpainting/glwidget.h
+++ b/examples/opengl/overpainting/glwidget.h
@@ -50,6 +50,7 @@
 #include <QTimer>
 
 class Bubble;
+class QtLogo;
 QT_BEGIN_NAMESPACE
 class QPaintEvent;
 class QWidget;
@@ -88,27 +89,24 @@ private slots:
     void animate();
 
 private:
-    GLuint makeObject();
     void createBubbles(int number);
     void drawInstructions(QPainter *painter);
 //! [1]
-    void extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2);
-    void normalizeAngle(int *angle);
-    void quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
-              GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4);
     void setupViewport(int width, int height);
 
+    QColor qtGreen;
+    QColor qtPurple;
+
     GLuint object;
     int xRot;
     int yRot;
     int zRot;
     QPoint lastPos;
-    QColor qtGreen;
-    QColor qtPurple;
 //! [4]
+    QtLogo *logo;
     QList<Bubble*> bubbles;
     QTimer animationTimer;
-};
 //! [4]
+};
 
 #endif
diff --git a/examples/opengl/overpainting/overpainting.pro b/examples/opengl/overpainting/overpainting.pro
index 10b6bd3..f9ba245 100644
--- a/examples/opengl/overpainting/overpainting.pro
+++ b/examples/opengl/overpainting/overpainting.pro
@@ -1,15 +1,23 @@
-QT          += opengl
+VPATH += ../shared
+INCLUDEPATH += ../shared
 
-HEADERS     = bubble.h \
-              glwidget.h
-SOURCES     = bubble.cpp \
-              glwidget.cpp \
-              main.cpp
+QT += opengl
+HEADERS = bubble.h \
+    glwidget.h \
+    qtlogo.h
+SOURCES = bubble.cpp \
+    glwidget.cpp \
+    main.cpp \
+    qtlogo.cpp
 
 # install
 target.path = $$[QT_INSTALL_EXAMPLES]/opengl/overpainting
-sources.files = $$SOURCES $$HEADERS $$RESOURCES $$FORMS overpainting.pro
+sources.files = $$SOURCES \
+    $$HEADERS \
+    $$RESOURCES \
+    $$FORMS \
+    overpainting.pro
 sources.path = $$[QT_INSTALL_EXAMPLES]/opengl/overpainting
-INSTALLS += target sources
-
-symbian: include($$QT_SOURCE_TREE/examples/symbianpkgrules.pri)
+INSTALLS += target \
+    sources
+symbian:include($$QT_SOURCE_TREE/examples/symbianpkgrules.pri)
diff --git a/examples/opengl/shared/qtlogo.cpp b/examples/opengl/shared/qtlogo.cpp
new file mode 100644
index 0000000..3294da1
--- /dev/null
+++ b/examples/opengl/shared/qtlogo.cpp
@@ -0,0 +1,403 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qtlogo.h"
+
+static const qreal tee_height = 0.311126;
+static const qreal cross_width = 0.25;
+static const qreal bar_thickness = 0.113137;
+static const qreal inside_diam = 0.20;
+static const qreal outside_diam = 0.30;
+static const qreal logo_depth = 0.10;
+static const int num_divisions = 32;
+
+//! [0]
+struct Geometry
+{
+    QVector<GLushort> faces;
+    QVector<QVector3D> vertices;
+    QVector<QVector3D> normals;
+    void appendSmooth(const QVector3D &a, const QVector3D &n, int from);
+    void appendFaceted(const QVector3D &a, const QVector3D &n);
+    void finalize();
+    void loadArrays() const;
+};
+//! [0]
+
+//! [1]
+class Patch
+{
+public:
+    enum Smoothing { Faceted, Smooth };
+    Patch(Geometry *);
+    void setSmoothing(Smoothing s) { sm = s; }
+    void translate(const QVector3D &t);
+    void rotate(qreal deg, QVector3D axis);
+    void draw() const;
+    void addTri(const QVector3D &a, const QVector3D &b, const QVector3D &c, const QVector3D &n);
+    void addQuad(const QVector3D &a, const QVector3D &b,  const QVector3D &c, const QVector3D &d);
+
+    GLushort start;
+    GLushort count;
+    GLushort initv;
+
+    GLfloat faceColor[4];
+    QMatrix4x4 mat;
+    Smoothing sm;
+    Geometry *geom;
+};
+//! [1]
+
+static inline void qSetColor(float colorVec[], QColor c)
+{
+    colorVec[0] = c.redF();
+    colorVec[1] = c.greenF();
+    colorVec[2] = c.blueF();
+    colorVec[3] = c.alphaF();
+}
+
+void Geometry::loadArrays() const
+{
+    glVertexPointer(3, GL_FLOAT, 0, vertices.constData());
+    glNormalPointer(GL_FLOAT, 0, normals.constData());
+}
+
+void Geometry::finalize()
+{
+    // TODO: add vertex buffer uploading here
+
+    // Finish smoothing normals by ensuring accumulated normals are returned
+    // to length 1.0.
+    for (int i = 0; i < normals.count(); ++i)
+        normals[i].normalize();
+}
+
+void Geometry::appendSmooth(const QVector3D &a, const QVector3D &n, int from)
+{
+    // Smooth normals are acheived by averaging the normals for faces meeting
+    // at a point.  First find the point in geometry already generated
+    // (working backwards, since most often the points shared are between faces
+    // recently added).
+    int v = vertices.count() - 1;
+    for ( ; v >= from; --v)
+        if (qFuzzyCompare(vertices[v], a))
+            break;
+    if (v < from)
+    {
+        // The vert was not found so add it as a new one, and initialize
+        // its corresponding normal
+        v = vertices.count();
+        vertices.append(a);
+        normals.append(n);
+    }
+    else
+    {
+        // Vert found, accumulate normals into corresponding normal slot.
+        // Must call finalize once finished accumulating normals
+        normals[v] += n;
+    }
+    // In both cases (found or not) reference the vert via its index
+    faces.append(v);
+}
+
+void Geometry::appendFaceted(const QVector3D &a, const QVector3D &n)
+{
+    // Faceted normals are achieved by duplicating the vert for every
+    // normal, so that faces meeting at a vert get a sharp edge.
+    int v = vertices.count();
+    vertices.append(a);
+    normals.append(n);
+    faces.append(v);
+}
+
+Patch::Patch(Geometry *g)
+   : start(g->faces.count())
+   , count(0)
+   , initv(g->vertices.count())
+   , sm(Patch::Smooth)
+   , geom(g)
+{
+    qSetColor(faceColor, QColor(Qt::darkGray));
+}
+
+void Patch::rotate(qreal deg, QVector3D axis)
+{
+    mat.rotate(deg, axis);
+}
+
+void Patch::translate(const QVector3D &t)
+{
+    mat.translate(t);
+}
+
+static inline void qMultMatrix(const QMatrix4x4 &mat)
+{
+    if (sizeof(qreal) == sizeof(GLfloat))
+        glMultMatrixf((GLfloat*)mat.constData());
+    else if (sizeof(qreal) == sizeof(GLdouble))
+        glMultMatrixd((GLdouble*)mat.constData());
+    else
+    {
+        GLfloat fmat[16];
+        qreal const *r = mat.constData();
+        for (int i = 0; i < 16; ++i)
+            fmat[i] = r[i];
+    }
+}
+
+//! [2]
+void Patch::draw() const
+{
+    glPushMatrix();
+    qMultMatrix(mat);
+    glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, faceColor);
+
+    const GLushort *indices = geom->faces.constData();
+    glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_SHORT, indices + start);
+    glPopMatrix();
+}
+//! [2]
+
+void Patch::addTri(const QVector3D &a, const QVector3D &b, const QVector3D &c, const QVector3D &n)
+{
+    QVector3D norm = n.isNull() ? QVector3D::normal(a, b, c) : n;
+    if (sm == Smooth)
+    {
+        geom->appendSmooth(a, norm, initv);
+        geom->appendSmooth(b, norm, initv);
+        geom->appendSmooth(c, norm, initv);
+    }
+    else
+    {
+        geom->appendFaceted(a, norm);
+        geom->appendFaceted(b, norm);
+        geom->appendFaceted(c, norm);
+    }
+    count += 3;
+}
+
+void Patch::addQuad(const QVector3D &a, const QVector3D &b,  const QVector3D &c, const QVector3D &d)
+{
+    QVector3D norm = QVector3D::normal(a, b, c);
+    if (sm == Smooth)
+    {
+        addTri(a, b, c, norm);
+        addTri(a, c, d, norm);
+    }
+    else
+    {
+        // If faceted share the two common verts
+        addTri(a, b, c, norm);
+        int k = geom->vertices.count();
+        geom->appendSmooth(a, norm, k);
+        geom->appendSmooth(c, norm, k);
+        geom->appendFaceted(d, norm);
+        count += 3;
+    }
+}
+
+static inline QVector<QVector3D> extrude(const QVector<QVector3D> &verts, qreal depth)
+{
+    QVector<QVector3D> extr = verts;
+    for (int v = 0; v < extr.count(); ++v)
+        extr[v].setZ(extr[v].z() - depth);
+    return extr;
+}
+
+class Rectoid
+{
+public:
+    void translate(const QVector3D &t)
+    {
+        for (int i = 0; i < parts.count(); ++i)
+            parts[i]->translate(t);
+    }
+    void rotate(qreal deg, QVector3D axis)
+    {
+        for (int i = 0; i < parts.count(); ++i)
+            parts[i]->rotate(deg, axis);
+    }
+
+    // No special Rectoid destructor - the parts are fetched out of this member
+    // variable, and destroyed by the new owner
+    QList<Patch*> parts;
+};
+
+class RectPrism : public Rectoid
+{
+public:
+    RectPrism(Geometry *g, qreal width, qreal height, qreal depth);
+};
+
+RectPrism::RectPrism(Geometry *g, qreal width, qreal height, qreal depth)
+{
+    enum { bl, br, tr, tl };
+    Patch *fb = new Patch(g);
+    fb->setSmoothing(Patch::Faceted);
+
+    // front face
+    QVector<QVector3D> r(4);
+    r[br].setX(width);
+    r[tr].setX(width);
+    r[tr].setY(height);
+    r[tl].setY(height);
+    QVector3D adjToCenter(-width / 2.0, -height / 2.0, depth / 2.0);
+    for (int i = 0; i < 4; ++i)
+        r[i] += adjToCenter;
+    fb->addQuad(r[bl], r[br], r[tr], r[tl]);
+
+    // back face
+    QVector<QVector3D> s = extrude(r, depth);
+    fb->addQuad(s[tl], s[tr], s[br], s[bl]);
+
+    // side faces
+    Patch *sides = new Patch(g);
+    sides->setSmoothing(Patch::Faceted);
+    sides->addQuad(s[bl], s[br], r[br], r[bl]);
+    sides->addQuad(s[br], s[tr], r[tr], r[br]);
+    sides->addQuad(s[tr], s[tl], r[tl], r[tr]);
+    sides->addQuad(s[tl], s[bl], r[bl], r[tl]);
+
+    parts << fb << sides;
+}
+
+class RectTorus : public Rectoid
+{
+public:
+    RectTorus(Geometry *g, qreal iRad, qreal oRad, qreal depth, int numSectors);
+};
+
+RectTorus::RectTorus(Geometry *g, qreal iRad, qreal oRad, qreal depth, int k)
+{
+    QVector<QVector3D> inside;
+    QVector<QVector3D> outside;
+    for (int i = 0; i < k; ++i) {
+        qreal angle = (i * 2 * M_PI) / k;
+        inside << QVector3D(iRad * qSin(angle), iRad * qCos(angle), depth / 2.0);
+        outside << QVector3D(oRad * qSin(angle), oRad * qCos(angle), depth / 2.0);
+    }
+    inside << QVector3D(0.0, iRad, 0.0);
+    outside << QVector3D(0.0, oRad, 0.0);
+    QVector<QVector3D> in_back = extrude(inside, depth);
+    QVector<QVector3D> out_back = extrude(outside, depth);
+
+    // Create front, back and sides as seperate patches so that smooth normals
+    // are generated for the curving sides, but a faceted edge is created between
+    // sides and front/back
+    Patch *front = new Patch(g);
+    for (int i = 0; i < k; ++i)
+        front->addQuad(outside[i], inside[i],
+                       inside[(i + 1) % k], outside[(i + 1) % k]);
+    Patch *back = new Patch(g);
+    for (int i = 0; i < k; ++i)
+        back->addQuad(in_back[i], out_back[i],
+                      out_back[(i + 1) % k], in_back[(i + 1) % k]);
+    Patch *is = new Patch(g);
+    for (int i = 0; i < k; ++i)
+        is->addQuad(in_back[i], in_back[(i + 1) % k],
+                    inside[(i + 1) % k], inside[i]);
+    Patch *os = new Patch(g);
+    for (int i = 0; i < k; ++i)
+        os->addQuad(out_back[(i + 1) % k], out_back[i],
+                    outside[i], outside[(i + 1) % k]);
+    parts << front << back << is << os;
+}
+
+QtLogo::QtLogo(QObject *parent, int divisions, qreal scale)
+    : QObject(parent)
+    , geom(new Geometry())
+{
+    buildGeometry(divisions, scale);
+}
+
+QtLogo::~QtLogo()
+{
+    qDeleteAll(parts);
+    delete geom;
+}
+
+void QtLogo::setColor(QColor c)
+{
+    for (int i = 0; i < parts.count(); ++i)
+        qSetColor(parts[i]->faceColor, c);
+}
+
+//! [3]
+void QtLogo::buildGeometry(int divisions, qreal scale)
+{
+    qreal cw = cross_width * scale;
+    qreal bt = bar_thickness * scale;
+    qreal ld = logo_depth * scale;
+    qreal th = tee_height *scale;
+
+    RectPrism cross(geom, cw, bt, ld);
+    RectPrism stem(geom, bt, th, ld);
+
+    QVector3D z(0.0, 0.0, 1.0);
+    cross.rotate(45.0, z);
+    stem.rotate(45.0, z);
+
+    qreal stem_downshift = (th + bt) / 2.0;
+    stem.translate(QVector3D(0.0, -stem_downshift, 0.0));
+
+    RectTorus body(geom, 0.20, 0.30, 0.1, divisions);
+
+    parts << stem.parts << cross.parts << body.parts;
+
+    geom->finalize();
+}
+//! [3]
+
+//! [4]
+void QtLogo::draw() const
+{
+    geom->loadArrays();
+
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glEnableClientState(GL_NORMAL_ARRAY);
+
+    for (int i = 0; i < parts.count(); ++i)
+        parts[i]->draw();
+
+    glDisableClientState(GL_VERTEX_ARRAY);
+    glDisableClientState(GL_NORMAL_ARRAY);
+}
+//! [4]
diff --git a/examples/opengl/shared/qtlogo.h b/examples/opengl/shared/qtlogo.h
new file mode 100644
index 0000000..26508e1
--- /dev/null
+++ b/examples/opengl/shared/qtlogo.h
@@ -0,0 +1,67 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QTLOGO_H
+#define QTLOGO_H
+
+#include <QObject>
+#include <QtOpenGL>
+
+class Patch;
+class Geometry;
+
+//! [0]
+class QtLogo : public QObject
+{
+public:
+    QtLogo(QObject *parent, int d = 64, qreal s = 1.0);
+    ~QtLogo();
+    void setColor(QColor c);
+    void draw() const;
+private:
+    void buildGeometry(int d, qreal s);
+
+    QList<Patch *> parts;
+    Geometry *geom;
+};
+//! [0]
+
+#endif // QTLOGO_H