sphere packing in Maya optimized

from pymel.all import *
import maya.OpenMaya as OpenMaya
import maya.mel as mel
import maya.cmds as cmds
import time

step = 100
######################################
def mag(p1,p2):
    return ((p1[0]-p2[0])**2+(p1[1]-p2[1])**2+(p1[2]-p2[2])**2)**.5

def fillOptimized():
    if(len(ls(sl=1))):
        obj=cmds.ls(sl=1)[0]
        objList = OpenMaya.MSelectionList()
        objList.add(obj)
        path = OpenMaya.MDagPath()
        objList.getDagPath(0,path)
        path.extendToShape()

        closest = OpenMaya.MMeshIntersector()

        closest.create(path.node(),path.inclusiveMatrix())

        try:
            particleFill(rs=step,maxX=1,maxY=1,maxZ=1,minX=0,minY=0,minZ=0,pd=1,cp=1)
        except:
            pass
        part = cmds.ls(sl=1)[0]
        partShape = cmds.listRelatives(part,shapes=1)[0]

        nplist = OpenMaya.MSelectionList()
        nplist.add(partShape)
        npobj = OpenMaya.MObject()
        nplist.getDependNode(0,npobj)

        npnode = OpenMaya.MFnDependencyNode(npobj)

        nplug = npnode.findPlug("position")

        nhdl = nplug.asMDataHandle()

        ndata = OpenMaya.MFnVectorArrayData(nhdl.data())

        points = OpenMaya.MVectorArray()

        points.copy(ndata.array())

        delete(part)

        rayons=OpenMaya.MDoubleArray()
        for p in range(points.length()):
            mpom = OpenMaya.MPointOnMesh()
            closest.getClosestPoint(OpenMaya.MPoint(points[p]),mpom)
            closestPoint = mpom.getPoint()
            rayons.append(mag(points[p],closestPoint))

        newPoints,newRayons = OpenMaya.MVectorArray(),OpenMaya.MDoubleArray()
        while points.length()>0:
            print "%s problem points still left..." % points.length()
            action,p,max,maxId = 0,OpenMaya.MVector(),-1.0,-1
            for i in range(points.length()):
                if rayons[i]>max:
                    max,p,maxId=rayons[i],points[i],i
            points.remove(maxId)
            rayons.remove(maxId)
            newPoints.append(p)
            newRayons.append(max*1.2)
            i=0
            while i<points.length():
                if mag(p,points[i])<rayons[i]+max:
                    points.remove(i)
                    rayons.remove(i)
                else:
                    i=i+1

        #note: the default nParticle creation mode should be set to "points"

        part = cmds.nParticle()[1]

        plist = OpenMaya.MSelectionList()

        plist.add(part)

        newNPObj = OpenMaya.MObject()

        plist.getDependNode(0,newNPObj)

        newNPNode = OpenMaya.MFnDependencyNode(newNPObj)

        newPosPlug = newNPNode.findPlug("position")

        newNPHdl = newPosPlug.asMDataHandle()

        newposdata = OpenMaya.MFnVectorArrayData(newNPHdl.data())

        newposdata.set(newPoints)

        newPosPlug.setMObject(newposdata.object())

        prt = newNPNode.findPlug("particleRenderType")

        prt.setInt(4)

        isg = newNPNode.findPlug("ignoreSolverGravity")

        isg.setInt(1)

        tattr = OpenMaya.MFnTypedAttribute()

        rpp = tattr.create("radiusPP","rpp",OpenMaya.MFnData.kDoubleArray)

        newNPNode.addAttribute(rpp)

        rppPlug = newNPNode.findPlug("radiusPP")

        rpphdl = rppPlug.asMDataHandle()

        rppdata = OpenMaya.MFnDoubleArrayData(rpphdl.data())

        rppdata.set(newRayons)

        rppPlug.setMObject(rppdata.object())

        print "finished."
    else:
        print("no mesh selected !")