tixxit

# Jarvis March O(nh) - Tom Switzer <[email protected]>

TURN_LEFT, TURN_RIGHT, TURN_NONE = (1, -1, 0)

def turn(p, q, r):
    """Returns -1, 0, 1 if p,q,r forms a right, straight, or left turn."""
    return cmp((q[0] - p[0])*(r[1] - p[1]) - (r[0] - p[0])*(q[1] - p[1]), 0)

def _dist(p, q):
    """Returns the squared Euclidean distance between p and q."""