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diff --git a/intern/python/modules/util/vectools.py b/intern/python/modules/util/vectools.py
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+++ b/intern/python/modules/util/vectools.py
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+"""Vector tools
+
+	Various vector tools, basing on vect.py"""
+
+from vect import *
+
+EPSILON = 0.0001
+
+def vecarea(v, w):
+	"Computes area of the span of vector 'v' and 'w' in 2D (not regarding z coordinate)"
+	return v[0]*w[1] - v[1]*w[0]
+
+def intersect(a1, b1, a2, b2):
+	"""Computes 2D intersection of edges ('a1' -> 'b1') and ('a2' -> 'b2'), 
+returning normalized intersection parameter 's' of edge (a1 -> b1). 
+If 0.0 < 's' <= 1.0,
+the two edges intersect at the point::
+
+	v = a1 + s * (b1 - a1)
+"""
+	v = (b1[0] - a1[0], b1[1] - a1[1])
+	w = (b2[0] - a2[0], b2[1] - a2[1])
+	d0 = (a2[0] - a1[0])
+	d1 = (a2[1] - a1[1])
+
+	det = w[0]*v[1] - w[1]*v[0]
+	if det == 0: return 0.0
+	t = v[0]*d1 - v[1]*d0
+	s = w[0]*d1 - w[1]*d0
+	s /= det
+	t /= det
+	if s > 1.0 or s < 0.0: return 0.0
+	if t > 1.0 or t < 0.0: return 0.0
+	return s
+
+def insidetri(a, b, c, x):
+	"Returns 1 if 'x' is inside the 2D triangle ('a' -> 'b' -> 'c'), 0 otherwise"
+	v1 = norm3(sub3(b, a))
+	v2 = norm3(sub3(c, a))
+	v3 = norm3(sub3(x, a))
+	
+	a1 = (vecarea(v1, v2))
+	a2 = (vecarea(v1, v3))
+	lo = min(0.0, a1)
+	hi = max(0.0, a1)
+
+	if a2 < lo or a2 > hi: return 0
+
+	v2 = norm3(sub3(b, c))
+	v3 = norm3(sub3(b, x))
+
+	a1 = (vecarea(v1, v2))
+	a2 = (vecarea(v1, v3))
+
+	lo = min(0.0, a1)
+	hi = max(0.0, a1)
+	
+	if a2 < lo or a2 > hi: return 0
+
+	return 1
+
+def plane_fromface(v1, v2, v3):
+	"Returns plane (normal, point) from 3 vertices 'v1', 'v2', 'v3'"
+	v = sub3(v2, v1)
+	w = sub3(v3, v1)
+	n = norm3(cross(v, w))
+	return n, v1
+
+def inside_halfspace(vec, plane):
+	"Returns 1 if point 'vec' inside halfspace defined by 'plane'"
+	n, t = plane
+ 	n = norm3(n)
+	v = sub3(vec, t)
+	if dot(n, v) < 0.0:
+		return 1
+	else:
+		return 0
+
+def half_space(vec, plane, tol = EPSILON):
+	"""Determine whether point 'vec' is inside (return value -1), outside (+1)
+, or lying in the plane 'plane' (return 0) of a numerical thickness 
+'tol' = 'EPSILON' (default)."""
+	n, t = plane
+	v = sub3(vec, t)
+	fac = len3(n)
+
+	d = dot(n, v)
+	if d < -fac * tol:
+		return -1
+	elif d > fac * tol:
+		return 1
+	else:
+		return 0
+	
+
+def plane_edge_intersect(plane, edge):
+	"""Returns normalized factor 's' of the intersection of 'edge' with 'plane'.
+The point of intersection on the plane is::
+
+	p = edge[0] + s * (edge[1] - edge[0])
+
+"""
+	n, t = plane # normal, translation
+	mat = matfromnormal(n)
+	mat = transmat(mat) # inverse
+	v = matxvec(mat, sub3(edge[0], t)) #transformed edge points
+	w = matxvec(mat, sub3(edge[1], t)) 
+	w = sub3(w, v)
+	if w[2] != 0.0:
+		s = -v[2] / w[2]
+		return s
+	else:
+		return None
+
+def insidecube(v):
+	"Returns 1 if point 'v' inside normalized cube, 0 otherwise"
+	if v[0] > 1.0 or v[0] < 0.0:
+		return 0
+	if v[1] > 1.0 or v[1] < 0.0:
+		return 0
+	if v[2] > 1.0 or v[2] < 0.0:
+		return 0
+	return 1
+
+
+def flatproject(verts, up):
+	"""Projects a 3D set (list of vertices) 'verts' into a 2D set according to
+an 'up'-vector"""
+	z, t = plane_fromface(verts[0], verts[1], verts[2])
+	y = norm3(up)
+	x = cross(y, z)
+	uvs = []
+	for v in verts:
+		w = (v[0] - t[0], v[1] - t[1], v[2] - t[2])
+		# this is the transposed 2x2 matrix * the vertex vector
+		uv = (dot(x, w), dot(y,w)) # do projection
+		uvs.append(uv)
+	return uvs
+
+
+
+