from OpenGL.GL import *
from OpenGL.GLUT import *
from OpenGL.GLU import *
import sys

def ecran():
    global pv # Le point de vue
    glClearColor(0,0,0,0)
    glClear(GL_COLOR_BUFFER_BIT)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    gluLookAt(pv[0],pv[1],pv[2],pv[3],pv[4],pv[5],pv[6],pv[7],pv[8])

    glColor3d(1,0,0)
    glBegin(GL_LINE_LOOP)
    glVertex3f(0.5,0.5,0.0)
    glVertex3f(0.,0.,1.0)
    glVertex3f(0.5,-0.5,0.0)
    glVertex3f(0.5,0.5,0.0)
    glVertex3f(-0.5,0.5,0.0)
    glVertex3f(0.,0.,1.0)
    glVertex3f(-0.5,-0.5,0.0)
    glVertex3f(-0.5,0.5,0.0)
    glVertex3f(0.5,0.5,0.0)
    glVertex3f(0.5,-0.5,0.0)
    glVertex3f(-0.5,-0.5,0.0)
    glVertex3f(-0.5,0.5,0.0)
    glEnd()
    glFlush()


def clavier(*args):
    global pv # Le point de vue
    if args[0] == 'q':
        sys.exit()
    elif args[0] == 'a':
        pv = (-2.,-1.,.0,0.,0.,0.,0.,0.,1.)
    elif args[0] == 'z':
        pv = (-2.,-1.,.5,0.,0.,0.,0.,0.,1.)
    elif args[0] == 'e':
        pv = (-2.,-1.,1.5,0.,0.,0.,0.,1.,1.)
    elif args[0] == 'r':
        pv = (-3.,-1.,.5,0.,0.,0.,0.,0.,1.)
    glutPostRedisplay()


def reshape(*args):
    glViewport(0,0,args[0],args[1])
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    gluPerspective(60.0,float(args[0])/args[1],1.,10.)


def main():
    global pv # Le point de vue
    pv = (-2.,-1.,.5,0.,0.,0.,0.,0.,1.)
    glutInit(sys.argv)
    glutInitDisplayMode(GLUT_RGBA)
    glutInitWindowPosition(100,100)
    glutInitWindowSize(320,320)
    glutCreateWindow("Une pyramide")
    glutDisplayFunc(ecran)
    glutKeyboardFunc(clavier)
    glutReshapeFunc(reshape)
    glutMainLoop()

main()