PMVC.pys

import math

def pointsOnSphere(N):
	N = float(N) # in case we got an int which we surely got 
	pts = [[],[],[]]
	inc = math.pi * (3 - math.sqrt(5)) 
	off = 2 / N 
	for k in range(0, int(N)): 
		y = k * off - 1 + (off / 2) 
		r = math.sqrt(1 - y*y) 
		phi = k * inc 
		pts[0].append(math.cos(phi)*r)
		pts[1].append(y)
		pts[2].append(math.sin(phi)*r)
	return pts
	
xsi = Application	
sparse = 1
c = xsi.Selection(1)
cPrim = c.Activeprimitive
cGeo = cPrim.Geometry
d = xsi.Selection(0)
dGeo = d.ActivePrimitive.Geometry
dPoints = dGeo.Points

#dGeo.RemoveICEAttribute("PMVWeight")
#dGeo.RemoveICEAttribute("PMVid")

nbSample = 64
Samples =  pointsOnSphere(nbSample)
PMVC = [[],[]]
area = math.pi*4/nbSample
for p in dPoints:
	w = [0]*cGeo.Points.Count
	pos = p.Position
	lPos = [pos.X,pos.Y,pos.Z]
	posArray = [[lPos[i] for j in range(nbSample)] for i in range(3)]
	loc = cGeo.GetRaycastIntersections( posArray, Samples,0 )
	aI = cGeo.EvaluatePositions(loc)
	aCoord = cGeo.GetTriangleWeightArray(loc)
	ID = cGeo.GetTriangleVertexIndexArray( loc )
	for s in range(nbSample):
		if ID[0][s] != -1:
			dist = XSIMath.CreateVector3(aI[0][s], aI[1][s], aI[2][s]) 
			dist.SubInPlace(pos)
			distScale = 1/dist.Length()*area
			x=aCoord[0][s]*distScale
			y=aCoord[1][s]*distScale
			z=aCoord[2][s]*distScale
			w[ID[0][s]]+=x
			w[ID[1][s]]+=y  
			w[ID[2][s]]+=z
	nW = []
	id = []
	tW = sum(w)
	if sparse == 0:
		for i in w:
			if i/tW < 0.000001:
				nW.append(0.0)
			else:
				nW.append(i/tW)
		PMVC[0].append(nW)
	else:
		j=0
		for i in w:
			if i/tW > 0.000001:
				nW.append(i/tW)
				id.append(j)
			j+=1
		PMVC[0].append(nW)
		PMVC[1].append(id)
attr = dGeo.AddIceAttribute("PMVWeight",4,2,2)
attr.DataArray2D = PMVC[0]
attr = dGeo.AddIceAttribute("PMVID",2,2,2)
attr.DataArray2D = PMVC[1]