1 files changed, 192 insertions, 0 deletions
diff --git a/examples/opengl/cube/mainwidget.cpp b/examples/opengl/cube/mainwidget.cpp
new file mode 100644
index 0000000..bead5f79
--- /dev/null
+++ b/examples/opengl/cube/mainwidget.cpp
@@ -0,0 +1,192 @@
+#include "mainwidget.h"
+
+#include "geometryengine.h"
+
+#include <QtOpenGL/QGLShaderProgram>
+
+#include <QBasicTimer>
+#include <QMouseEvent>
+
+#include <math.h>
+
+#include <QDebug>
+
+MainWidget::MainWidget(QWidget *parent) :
+    QGLWidget(parent),
+    timer(new QBasicTimer),
+    program(new QGLShaderProgram),
+    geometries(new GeometryEngine)
+{
+}
+
+MainWidget::~MainWidget()
+{
+    delete timer; timer = 0;
+    delete program; program = 0;
+    delete geometries; geometries = 0;
+
+    deleteTexture(texture);
+}
+
+//! [0]
+void MainWidget::mousePressEvent(QMouseEvent *e)
+{
+    // Saving mouse press position
+    mousePressPosition = QVector2D(e->posF());
+}
+
+void MainWidget::mouseReleaseEvent(QMouseEvent *e)
+{
+    // Mouse release position - mouse press position
+    QVector2D diff = QVector2D(e->posF()) - mousePressPosition;
+
+    // Rotation axis is perpendicular to the mouse position difference 
+    // vector
+    QVector3D n = QVector3D(diff.y(), diff.x(), 0.0).normalized();
+
+    // Accelerate angular speed relative to the length of the mouse sweep
+    qreal acc = diff.length() / 100.0;
+
+    // Calculate new rotation axis as weighted sum
+    rotationAxis = (rotationAxis * angularSpeed + n * acc).normalized();
+
+    // Increase angular speed
+    angularSpeed += acc;
+}
+//! [0]
+
+//! [1]
+void MainWidget::timerEvent(QTimerEvent *e)
+{
+    Q_UNUSED(e);
+
+    // Decrease angular speed (friction)
+    angularSpeed *= 0.99;
+
+    // Stop rotation when speed goes below threshold
+    if (angularSpeed < 0.01)
+        angularSpeed = 0.0;
+    else {
+        // Update rotation
+        rotation = QQuaternion::fromAxisAndAngle(rotationAxis, angularSpeed) * rotation;
+
+        // Update scene
+        updateGL();
+    }
+}
+//! [1]
+
+void MainWidget::initializeGL()
+{
+    qglClearColor(Qt::black);
+
+    qDebug() << "Initializing shaders...";
+    initShaders();
+
+    qDebug() << "Initializing textures...";
+    initTextures();
+
+//! [2]
+    // Enable depth buffer
+    glEnable(GL_DEPTH_TEST);
+
+    // Enable back face culling
+    glEnable(GL_CULL_FACE);
+//! [2]
+
+    qDebug() << "Initializing geometries...";
+    geometries->init();
+
+    // using QBasicTimer because its faster that QTimer
+    timer->start(12, this);
+}
+
+//! [3]
+void MainWidget::initShaders()
+{
+    // Overriding system locale until shaders are compiled
+    setlocale(LC_NUMERIC, "C");
+
+    // Compiling vertex shader
+    if (!program->addShaderFromSourceFile(QGLShader::Vertex, ":/vshader.glsl"))
+        close();
+
+    // Compiling fragment shader
+    if (!program->addShaderFromSourceFile(QGLShader::Fragment, ":/fshader.glsl"))
+        close();
+
+    // Linking shader pipeline
+    if (!program->link())
+        close();
+
+    // Binding shader pipeline for use
+    if (!program->bind())
+        close();
+
+    // Restore system locale
+    setlocale(LC_ALL, "");
+}
+//! [3]
+
+//! [4]
+void MainWidget::initTextures()
+{
+    // Loading cube.png to texture unit 0
+    glActiveTexture(GL_TEXTURE0);
+    glEnable(GL_TEXTURE_2D);
+    texture = bindTexture(QImage(":/cube.png"));
+
+    // Set nearest filtering mode for texture minification
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+    // Set bilinear filtering mode for texture magnification
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+    // Wrap texture coordinates by repeating
+    // f.ex. texture coordinate (1.1, 1.2) is same as (0.1, 0.2)
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+}
+//! [4]
+
+//! [5]
+void MainWidget::resizeGL(int w, int h)
+{
+    // Set OpenGL viewport to cover whole widget
+    glViewport(0, 0, w, h);
+
+    // Calculate aspect ratio
+    qreal aspect = (qreal)w / ((qreal)h?h:1);
+
+    // Set near plane to 3.0, far plane to 7.0, field of view 45 degrees
+    const qreal zNear = 3.0, zFar = 7.0, fov = 45.0;
+
+    // Reset projection
+    projection.setToIdentity();
+
+    // Set perspective projection
+    projection.perspective(fov, aspect, zNear, zFar);
+}
+//! [5]
+
+void MainWidget::paintGL()
+{
+    // Clear color and depth buffer
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+//! [6]
+    // Calculate model view transformation
+    QMatrix4x4 matrix;
+    matrix.translate(0.0, 0.0, -5.0);
+    matrix.rotate(rotation);
+
+    // Set modelview-projection matrix
+    program->setUniformValue("mvp_matrix", projection * matrix);
+//! [6]
+
+    // Using texture unit 0 which contains cube.png
+    program->setUniformValue("texture", 0);
+
+    // Draw cube geometry
+    geometries->drawCubeGeometry(program);
+}