root/branches/Carsten_PtrWork2/Tutorials/01hello.cpp

// OpenSG Tutorial Example: Hello World
//
// Minimalistic OpenSG program
// 
// This is the shortest useful OpenSG program 
// (if you remove all the comments ;)
//
// It shows how to use OpenSG together with GLUT to create a little
// interactive scene viewer.
//

// GLUT is used for window handling
#include <OpenSG/OSGGLUT.h>

// General OpenSG configuration, needed everywhere
#include <OpenSG/OSGConfig.h>

// Methods to create simple geometry: boxes, spheres, tori etc.
#include <OpenSG/OSGSimpleGeometry.h>

// The GLUT-OpenSG connection class
#include <OpenSG/OSGGLUTWindow.h>

// A little helper to simplify scene management and interaction
#include <OpenSG/OSGSimpleSceneManager.h>

// Activate the OpenSG namespace
// This is not strictly necessary, you can also prefix all OpenSG symbols
// with OSG::, but that would be a bit tedious for this example
OSG_USING_NAMESPACE

// The SimpleSceneManager to manage simple applications
SimpleSceneManager *mgr;

// forward declaration so we can have the interesting stuff upfront
int setupGLUT( int *argc, char *argv[] );

// Initialize GLUT & OpenSG and set up the scene
int main(int argc, char **argv)
{
    std::cerr << "-- BEGIN main --" << std::endl;

    // OSG init
    osgInit(argc,argv);

    // GLUT init
    int winid = setupGLUT(&argc, argv);

    // the connection between GLUT and OpenSG
    GLUTWindowGlobalRefPtr gwin = GLUTWindow::create();
    gwin->setGlutId(winid);
    gwin->init();

    // create the scene
    NodeGlobalRefPtr scene = makeTorus(.5, 2, 16, 16);

    commitChanges();

    // create the SimpleSceneManager helper
    mgr = new SimpleSceneManager;

    // tell the manager what to manage
    mgr->setWindow(gwin );
    mgr->setRoot  (scene);

    // show the whole scene
    mgr->showAll();
    
    // GLUT main loop
    glutMainLoop();
    
    std::cerr << "-- END   main --" << std::endl;
    
    return 0;
}

//
// GLUT callback functions
//

// redraw the window
void display(void)
{
    std::cerr << "-- BEGIN Frame --" << std::endl;
    
    mgr->redraw();
    
    std::cerr << "-- END   Frame --" << std::endl;
}

// react to size changes
void reshape(int w, int h)
{
    mgr->resize(w, h);
    glutPostRedisplay();
}

// react to mouse button presses
void mouse(int button, int state, int x, int y)
{
    if (state)
        mgr->mouseButtonRelease(button, x, y);
    else
        mgr->mouseButtonPress(button, x, y);
        
    glutPostRedisplay();
}

// react to mouse motions with pressed buttons
void motion(int x, int y)
{
    mgr->mouseMove(x, y);
    glutPostRedisplay();
}

// react to keys
void keyboard(unsigned char k, int x, int y)
{
    switch(k)
    {
        case 27:        
        {
            delete mgr;
        
            OSG::osgExit();
            exit(0);
        }
        break;

        case 's':
        {
            mgr->setStatistics(!mgr->getStatistics());
        }
        break;
    }
}

// setup the GLUT library which handles the windows for us
int setupGLUT(int *argc, char *argv[])
{
    glutInit(argc, argv);
    glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
    
    int winid = glutCreateWindow("OpenSG");
    
    glutReshapeFunc(reshape);
    glutDisplayFunc(display);
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    glutKeyboardFunc(keyboard);

    return winid;
}