def window(w=800,h=800,title='light',px=100,py=100):

    #glut init
    glut.glutInit(sys.argv)
    glut.glutInitDisplayMode (glut.GLUT_DOUBLE | glut.GLUT_RGB)
    glut.glutInitWindowSize (w, h)
    glut.glutInitWindowPosition (px, py)
    glut.glutCreateWindow (title)