source: trunk/examples/opengl/framebufferobject2/glwidget.cpp@ 875

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#include "glwidget.h"
#include <QtGui/QImage>

#include <math.h>

static GLint cubeArray[][3] = {
    {0, 0, 0}, {0, 1, 0}, {1, 1, 0}, {1, 0, 0},
    {0, 0, 1}, {1, 0, 1}, {1, 1, 1}, {0, 1, 1},
    {0, 0, 0}, {1, 0, 0}, {1, 0, 1}, {0, 0, 1},
    {0, 1, 0}, {0, 1, 1}, {1, 1, 1}, {1, 1, 0},
    {0, 1, 0}, {0, 0, 0}, {0, 0, 1}, {0, 1, 1},
    {1, 0, 0}, {1, 1, 0}, {1, 1, 1}, {1, 0, 1}
};

static GLint cubeTextureArray[][2] = {
    {0, 0}, {1, 0}, {1, 1}, {0, 1},
    {0, 0}, {0, 1}, {1, 1}, {1, 0},
    {0, 0}, {1, 0}, {1, 1}, {0, 1},
    {1, 0}, {0, 0}, {0, 1}, {1, 1},
    {0, 0}, {1, 0}, {1, 1}, {0, 1},
    {1, 0}, {0, 0}, {0, 1}, {1, 1}
};

static GLint faceArray[][2] = {
    {1, -1}, {1, 1}, {-1, 1}, {-1, -1}
};

static GLubyte colorArray[][4] = {
    {102, 176, 54, 255},
    {81, 141, 41, 255},
    {62, 108, 32, 255},
    {45, 79, 23, 255}
};

GLWidget::GLWidget(QWidget *parent)
  : QGLWidget(QGLFormat(QGL::SampleBuffers), parent)
{
    // create the framebuffer object - make sure to have a current
    // context before creating it
    makeCurrent();
    fbo = new QGLFramebufferObject(512, 512);
    timerId = startTimer(20);
    setWindowTitle(tr("OpenGL framebuffer objects 2"));
}

GLWidget::~GLWidget()
{
    glDeleteLists(pbufferList, 1);
    delete fbo;
}

void GLWidget::initializeGL()
{
    glMatrixMode(GL_MODELVIEW);

    glEnable(GL_CULL_FACE);

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glVertexPointer(3, GL_INT, 0, cubeArray);
    glTexCoordPointer(2, GL_INT, 0, cubeTextureArray);
    glColorPointer(4, GL_UNSIGNED_BYTE, 0, colorArray);

    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glEnable(GL_BLEND);
    glEnable(GL_TEXTURE_2D);
    glEnable(GL_DEPTH_TEST);

    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
    pbufferList = glGenLists(1);
    glNewList(pbufferList, GL_COMPILE);
    {
        glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);

        // draw cube background
        glPushMatrix();
        glLoadIdentity();
        glTranslatef(0.5f, 0.5f, -2.0f);
        glDisable(GL_TEXTURE_2D);