rem: printf("redraw\n");
context: void display(void){    printf("redraw\n");    // redraw the cluster window    mgr->redraw();    // clear change list. If you don't clear the changelist,    // then the same changes will be transmitted a socond time    // in the next frame.     OSG::Thread::getCurrentChangeList()->clearAll();    // clear local navigation window    glClear(GL_COLOR_BUFFER_BIT);    glutSwapBuffers();}