from Nurbs import Crv
import Numeric

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

lastx = 0
lasty = 0

def on_motion(x, y):
    # store the mouse coordinate
    global lastx, lasty
    lastx = x
    lasty = y
    # redisplay
    glutPostRedisplay()

def on_reshape(width, height):
    # setup the viewport
    glViewport(0, 0, width, height)
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    aspect = float(width)/float(height)
    if aspect < 1.:
        glOrtho(-10., 20., -10. / aspect, 20. / aspect, -25., 25.)
    else:
        glOrtho(-10. * aspect, 20. * aspect, -10., 20., -25., 25.)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
        
def on_display():
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    
    global lastx, lasty
    glRotatef(lastx, 0.0, 1.0, 0.0)
    glRotatef(lasty, 1.0, 0.0, 0.0)
    
    glCallList(1)
    
    glutSwapBuffers()

def main():
    glutInit(sys.argv)
    glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_ALPHA | GLUT_DEPTH)
    glutInitWindowSize(640, 480)
    glutCreateWindow('GLSrf - Press MB and drag to rotate')

    glutMotionFunc(on_motion)
    glutDisplayFunc(on_display)
    glutReshapeFunc(on_reshape)
    
    nurb = gluNewNurbsRenderer()
    
    glMatrixMode(GL_MODELVIEW)
    
    glNewList(1, GL_COMPILE)
    
    cntrl = [[-5., -7.5, 2.5, 0, -2.5, 7.5, 5.0],
                 [2.5, 5.0, 5.0, .0, -5.0, -5.0, 2.5]]
    knots = [0., 0., 0., .2, .4, .6, .8, 1., 1., 1.]
    
    #crv = Crv.Crv(cntrl, knots)
    crv = Crv.Circle(radius=10)
    #crv = Crv.Line(p1=(0,0,0), p2=(10,10,10))

    glPointSize(10.)
    glDisable(GL_LIGHTING)
    glColor3f(1., 1., 1.)

    glBegin(GL_POINTS)
    for i in range(crv.cntrl.shape[1]):
        w = crv.cntrl[-1,i]
        glVertex3f(crv.cntrl[0, i]/w, crv.cntrl[1, i]/w, crv.cntrl[2, i]/w)
    glEnd()
    
    glBegin(GL_LINE_STRIP)
    for i in range(crv.cntrl.shape[1]):
        w = crv.cntrl[-1,i]
        glVertex3f(crv.cntrl[0, i]/w, crv.cntrl[1, i]/w, crv.cntrl[2, i]/w)
    glEnd()
    
    glColor3f(1., 1., 0.)
    gluBeginCurve(nurb)
    gluNurbsCurve(nurb, crv.uknots, Numeric.transpose(crv.cntrl), GL_MAP1_VERTEX_4)
    gluEndCurve(nurb)

    glEndList()

if __name__ == '__main__':
    try:
        GLU_VERSION_1_2
    except:
        print "Need GLU 1.2 to run this demo"
        sys.exit(1)
    main()
    glutMainLoop()