Option Explicit
'Script written by Howard Jiho Kim
'Script version December 22, 2008
Call Diffuse()

Sub Diffuse()

	Dim aCrvs : aCrvs = Rhino.GetObjects("Select Curves", 4)
 
	Dim devRate : devRate = 0.01
	Dim vecLenMax : vecLenMax = 1
	Dim vecLenMin : vecLenMin = 3
	Dim noParticle : noParticle = 100

	Dim i,n
	Dim aPts()
	Dim crvDom, crvParam, crvLen
	
	Randomize
	
	For i = 0 To UBound(aCrvs)
 
		n = 0
		Dim strCrv : strCrv = aCrvs(i)
 
		crvDom = Rhino.CurveDomain(strCrv)
		crvLen = Rhino.CurveLength(strCrv)
  
		Rhino.EnableRedraw False
  
		Do Until n = noParticle
  
			crvParam = (RN(0.00, 1.00)) * (crvDom(1))
  
			ReDim Preserve aPts(n)
			aPts(n) = Rhino.EvaluateCurve(strCrv, crvParam)
						
			Dim devPt : devPt = aPts(n)
			Dim devX : devX = crvLen * devRate * RN(-1,1) + devPt(0)
			Dim devY : devY = crvLen * devRate * RN(-1,1) + devPt(1)
			Dim devZ : devZ = crvLen * devRate * RN(-1,1) + devPt(2)
			Dim devPt2 : devPt2 = Array(devX, devY, devZ)
			
			Dim rndPt : rndPt = Array(RN(-1,1), RN(-1,1), RN(-1,1))
			Dim rndPt2 : rndPt2 = Rhino.PointAdd(devPt2, rndPt)
   
			If n >= 1 Then
				Dim vecDir : vecDir = rhino.AddLine(devPt2, rndPt2)
				Dim vecLen : vecLen = RN(vecLenMin, vecLenMax)
				Dim Xform : Xform = Rhino.XformScale(devPt2, vecLen)
				
				Rhino.TransformObject vecDir, Xform, True
			End If

			n = n + 1
    
		Loop
 
		Rhino.EnableRedraw True
	Next
End Sub
Function RN (nMin, nMax)
	RN = Null
	Randomize
	RN = (nMax - nMin) * Rnd + nMin
End Function