spiro.py 文件源码

def spiro(num_teeth_fixed, num_teeth_move, height, num_segs, outfile):
    N = abs(num_teeth_fixed)
    D = abs(num_teeth_move)
    side_sign = num_teeth_move/D
    height = height*D/N
    num_segs = num_segs

    turns = D/fractions.gcd(N, D)
    print('OFF\n{} 1 0'.format(num_segs), file=outfile)

    for i in range(num_segs):
        ang_fixed = 2*math.pi*turns*i/num_segs
        ang_move = side_sign * ang_fixed * N/D
        move_cent = [math.cos(ang_fixed)*(N + side_sign*D)/N,
                     math.sin(ang_fixed)*(N + side_sign*D)/N, 0]
        move_offset = [height*math.cos(ang_fixed+ang_move),
                       height*math.sin(ang_fixed+ang_move), 0]
        P = [move_cent[i] + move_offset[i] for i in range(3)]
        print(P[0], P[1], P[2], file=outfile)

    print(num_segs, *[i for i in range(num_segs)], file=outfile)