examples/opengl/pbuffers/glwidget.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/opengl/pbuffers/glwidget.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,237 @@
+/****************************************************************************
+**
+** 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 "glwidget.h"
+#include <math.h>
+
+#include "cube.h"
+
+#include <QGLPixelBuffer>
+
+#ifndef GL_MULTISAMPLE
+#define GL_MULTISAMPLE  0x809D
+#endif
+
+static GLfloat colorArray[][4] = {
+    {0.243f, 0.423f, 0.125f, 1.0f},
+    {0.176f, 0.31f, 0.09f, 1.0f},
+    {0.4f, 0.69f, 0.212f, 1.0f},
+    {0.317f, 0.553f, 0.161f, 1.0f}
+};
+
+GLWidget::GLWidget(QWidget *parent)
+    : QGLWidget(QGLFormat(QGL::SampleBuffers), parent)
+    , geom(0)
+    , cube(0)
+{
+    // create the pbuffer
+    pbuffer = new QGLPixelBuffer(QSize(512, 512), format(), this);
+    setWindowTitle(tr("OpenGL pbuffers"));
+    initializeGeometry();
+}
+
+GLWidget::~GLWidget()
+{
+    pbuffer->releaseFromDynamicTexture();
+    glDeleteTextures(1, &dynamicTexture);
+    delete pbuffer;
+
+    qDeleteAll(cubes);
+    qDeleteAll(tiles);
+    delete cube;
+}
+
+void GLWidget::initializeGL()
+{
+    initCommon();
+    glShadeModel(GL_SMOOTH);
+    glEnable(GL_LIGHTING);
+    glEnable(GL_LIGHT0);
+    static GLfloat lightPosition[4] = { 0.5, 5.0, 7.0, 1.0 };
+    glLightfv(GL_LIGHT0, GL_POSITION, lightPosition);
+    initPbuffer();
+    cube->startAnimation();
+    connect(cube, SIGNAL(changed()), this, SLOT(update()));
+    for (int i = 0; i < 3; ++i)
+    {
+        cubes[i]->startAnimation();
+        connect(cubes[i], SIGNAL(changed()), this, SLOT(update()));
+    }
+}
+
+void GLWidget::paintGL()
+{
+    pbuffer->makeCurrent();
+    drawPbuffer();
+    // On direct render platforms, drawing onto the pbuffer context above
+    // automatically updates the dynamic texture.  For cases where rendering
+    // directly to a texture is not supported, explicitly copy.
+    if (!hasDynamicTextureUpdate)
+        pbuffer->updateDynamicTexture(dynamicTexture);
+    makeCurrent();
+
+    // Use the pbuffer as a texture to render the scene
+    glBindTexture(GL_TEXTURE_2D, dynamicTexture);
+
+    // set up to render the scene
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glLoadIdentity();
+    glTranslatef(0.0f, 0.0f, -10.0f);
+
+    // draw the background
+    glPushMatrix();
+    glScalef(aspect, 1.0f, 1.0f);
+    for (int i = 0; i < tiles.count(); ++i)
+        tiles[i]->draw();
+    glPopMatrix();
+
+    // draw the bouncing cubes
+    for (int i = 0; i < cubes.count(); ++i)
+        cubes[i]->draw();
+}
+
+void GLWidget::initializeGeometry()
+{
+    geom = new Geometry();
+    CubeBuilder cBuilder(geom, 0.5);
+    cBuilder.setColor(QColor(255, 255, 255, 212));
+    // build the 3 bouncing, spinning cubes
+    for (int i = 0; i < 3; ++i)
+        cubes.append(cBuilder.newCube(QVector3D((float)(i-1), -1.5f, 5 - i)));
+
+    // build the spinning cube which goes in the dynamic texture
+    cube = cBuilder.newCube();
+    cube->removeBounce();
+
+    // build the background tiles
+    TileBuilder tBuilder(geom);
+    tBuilder.setColor(QColor(Qt::white));
+    for (int c = -2; c <= +2; ++c)
+        for (int r = -2; r <= +2; ++r)
+            tiles.append(tBuilder.newTile(QVector3D(c, r, 0)));
+
+    // graded backdrop for the pbuffer scene
+    TileBuilder bBuilder(geom, 0.0f, 2.0f);
+    bBuilder.setColor(QColor(102, 176, 54, 210));
+    backdrop = bBuilder.newTile(QVector3D(0.0f, 0.0f, -1.5f));
+    backdrop->setColors(colorArray);
+}
+
+void GLWidget::initCommon()
+{
+    qglClearColor(QColor(Qt::darkGray));
+
+    glEnable(GL_DEPTH_TEST);
+    glEnable(GL_CULL_FACE);
+    glEnable(GL_MULTISAMPLE);
+
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    glEnable(GL_BLEND);
+
+    glEnable(GL_TEXTURE_2D);
+
+    geom->loadArrays();
+}
+
+void GLWidget::perspectiveProjection()
+{
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glFrustum(-aspect, +aspect, -1.0, +1.0, 4.0, 15.0);
+    glMatrixMode(GL_MODELVIEW);
+}
+
+void GLWidget::orthographicProjection()
+{
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    glOrtho(-1.0, +1.0, -1.0, +1.0, -90.0, +90.0);
+    glMatrixMode(GL_MODELVIEW);
+}
+
+void GLWidget::resizeGL(int width, int height)
+{
+    glViewport(0, 0, width, height);
+    aspect = (qreal)width / (qreal)(height ? height : 1);
+    perspectiveProjection();
+}
+
+void GLWidget::drawPbuffer()
+{
+    orthographicProjection();
+
+    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+    glDisable(GL_TEXTURE_2D);
+    backdrop->draw();
+    glEnable(GL_TEXTURE_2D);
+
+    glBindTexture(GL_TEXTURE_2D, cubeTexture);
+    glDisable(GL_CULL_FACE);
+    cube->draw();
+    glEnable(GL_CULL_FACE);
+
+    glFlush();
+}
+
+void GLWidget::initPbuffer()
+{
+    pbuffer->makeCurrent();
+
+    cubeTexture = bindTexture(QImage(":res/cubelogo.png"));
+
+    initCommon();
+
+    // generate a texture that has the same size/format as the pbuffer
+    dynamicTexture = pbuffer->generateDynamicTexture();
+
+    // bind the dynamic texture to the pbuffer - this is a no-op under X11
+    hasDynamicTextureUpdate = pbuffer->bindToDynamicTexture(dynamicTexture);
+    makeCurrent();
+}
+
+void GLWidget::setAnimationPaused(bool enable)
+{
+    cube->setAnimationPaused(enable);
+    for (int i = 0; i < 3; ++i)
+        cubes[i]->setAnimationPaused(enable);
+}