Option Explicit
'Script written by <David Mans>
'Script copyrighted by <Neoarchaic Design>
'Script version Tuesday, January 06, 2009 8:42:52 PM

Call Main()
Sub Main()
	Dim strReturn, curve, dom, distance, percent, origin
	'Select Curve to Evaluate
	curve = Rhino.GetObject("Select Curve",4)
	If isNull(curve) Then Exit Sub
	reparameterize(curve)

	'Choose Method for Curve Evaluation Parameter of Origin
	strReturn = Rhino.GetString("Evaluate Curve From ","Start",array("Start","Middle","End","Percent","Point"))
	If isNull(strReturn) Then Exit Sub

	'Set Parameter Based on Results
	dom = Rhino.CurveDomain(curve)
	If strReturn = "Start" Then
		origin = dom(0)
	ElseIf strReturn = "Middle" Then
		origin = dom(0)+(dom(1)-dom(0))*0.5
	ElseIf strReturn = "End" Then
		origin = dom(1)
	ElseIf strReturn = "Percent" Then

		percent = Rhino.GetReal("Percent",50,0,100)
		If isNull(percent) Then Exit Sub

		If percent = 0 Then
			origin = dom(0)
		Else
			origin = dom(0)+(dom(1)-dom(0))*(percent*0.01)
		End If
	ElseIf strReturn = "Point" Then
		origin = Rhino.CurveClosestPoint(curve,Rhino.GetPointOnCurve(curve))
		If isNull(origin) Then Exit Sub
	End If

	'Specify Increment Length with which to Evaluate Curve
	distance = Rhino.GetReal("Division Length",10)
	If isNull(distance) Then Exit Sub

	Dim i, j, evalCurve

	Call Rhino.EnableRedraw(False)
	evalCurve = evalCrvByDist(curve, distance, origin)

	For i = 0 To 1 Step 1
		For j = 1 To uBound(evalCurve(i)) Step 1
			Call Rhino.AddTextDot(j,evalCurve(i)(j))
			Call Rhino.AddLine(evalCurve(i)(j-1),evalCurve(i)(j))
		Next
	Next
	Call Rhino.EnableRedraw(True)

End Sub
Function evalCrvByDist(curve,distance, origin)
	evalCrvByDist = Null
	Dim i, j, k, r, s, t
	Dim sphere
	Dim tInt(), pt(), tempT(),pts(1)
	r=0: s=0

	For k = 0 To 1 Step 1
		t = origin
		r=0
		ReDim Preserve pt(r)

		pt(r) = Rhino.EvaluateCurve(curve,t)

		Do
			j=0

			ReDim tempT(0)
			ReDim Preserve tInt(r)

			sphere = Rhino.AddSphere(pt(r),distance)
			tInt(r) = Rhino.CurveSurfaceIntersection(curve,sphere)
			Call Rhino.DeleteObject(sphere)

			For i = 0 To uBound(tInt(r)) Step 1
				If k = 0 Then
					If tInt(r)(i, 0) = 1 And tInt(r)(i,5) > t Then
						s=s+1
						ReDim Preserve tempT(j)
						tempT(j) = tInt(r)(i,5)
						j=j+1
					End If
				Else
					If tInt(r)(i, 0) = 1 And tInt(r)(i,5) < t Then
						s=s+1
						ReDim Preserve tempT(j)
						tempT(j) = tInt(r)(i,5)
						j=j+1
					End If
				End If
			Next

			If s = 0 Then Exit Do
			If k = 0 Then
				t = Rhino.Min(tempT)
			Else
				t = Rhino.Max(tempT)
			End If
			r=r+1
			ReDim Preserve pt(r)
			pt(r) = Rhino.EvaluateCurve(curve,t)
			s=0
		Loop
		pts(k) = pt
	Next
	evalCrvByDist = pts
End Function
Function reparameterize(strObjectID)
	If Rhino.IsCurve(strObjectID) = True Then
		Call rhino.SelectObject(strObjectID)
		Call rhino.Command("reparameterize 0 1",False)
		Call rhino.UnselectAllObjects()
	End If
	If Rhino.IsSurface(strObjectID) = True Then
		Call rhino.SelectObject(strObjectID)
		Call rhino.Command("reparameterize 0 1 0 1",False)
		Call rhino.UnselectAllObjects()
	End If
End Function