def intersect_circle_plane(center, radius, direction, triangle):
# let n be the normal to the plane
n = triangle.normal
if n.dot(direction) == 0:
return (None, None, INFINITE)
# project onto z=0
n2 = Point(n.x, n.y, 0)
if n2.norm == 0:
(cp, d) = triangle.plane.intersect_point(direction, center)
ccp = cp.sub(direction.mul(d))
return (ccp, cp, d)
n2 = n2.normalized()
# the cutter contact point is on the circle, where the surface normal is n
ccp = center.add(n2.mul(-radius))
# intersect the plane with a line through the contact point
(cp, d) = triangle.plane.intersect_point(direction, ccp)
return (ccp, cp, d)
def intersect_circle_plane(center, radius, direction, triangle):
# let n be the normal to the plane
n = triangle.normal
if n.dot(direction) == 0:
return (None, None, INFINITE)
# project onto z=0
n2 = Point(n.x, n.y, 0)
if n2.norm == 0:
(cp, d) = triangle.plane.intersect_point(direction, center)
ccp = cp.sub(direction.mul(d))
return (ccp, cp, d)
n2 = n2.normalized()
# the cutter contact point is on the circle, where the surface normal is n
ccp = center.add(n2.mul(-radius))
# intersect the plane with a line through the contact point
(cp, d) = triangle.plane.intersect_point(direction, ccp)
return (ccp, cp, d)
