Option Explicit
'
'Script written by Dimitrie Stefanescu
'Released under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0
'№ 5:28:35 AMW ednesday, May 21, 2008

Dim surf

Call Main()
Sub Main()
	
	surf = Rhino.GetObject("sel surf ", 8, True)
	
	Dim detailLevel : detailLevel = Rhino.GetInteger("det lev/density x y ", 10, 5, 50)
	Dim hght : hght = Rhino.GetReal("rib height ", 0.5)
	
	Dim uDomain : uDomain = Rhino.SurfaceDomain(surf, 0)
	Dim uStep : uStep = (uDomain(1) - uDomain(0))/detailLevel
  
	Dim vDomain : vDomain = Rhino.SurfaceDomain(surf, 1)
	Dim vStep : vStep = (vDomain(1) - vDomain(0))/detailLevel
	
	Call rhino.enableredraw(False)
	
	Dim firstLine : firstLine = Array()
	Dim secondLine : secondLine = Array()
	
	ReDim firstLine(detailLevel)
	ReDim secondLine(detailLevel)
	
	Dim i, j, k : k = -1
	Dim ribArr : ribArr = Array()
	Dim n : n = -1
	Dim rib
	
	'Dim sgn : sgn = 0
	Dim m, mm : m = 0 : mm = 0
	
	For i=uDomain(0) To uDomain(1) Step uStep*2
		Dim sgn : sgn = 0
		For j=vDomain(0) To vDomain(1) Step vStep
			
			k = k + 1
			ReDim Preserve firstLine(k)
			ReDim Preserve secondLine(k)  
			
			If sgn < 2 Then
				firstLine(k) = Rhino.EvaluateSurface(surf, Array(i, j))
				If(m > 0) Then
					secondLine(k) = Rhino.EvaluateSurface(surf, Array(i, j))
				End If			
			End If
			
			If ((sgn <4) And (sgn>1)) Then
				firstLine(k) = Rhino.EvaluateSurface(surf, Array(i + uStep, j))
				If(m > 0) Then
					secondLine(k) = Rhino.EvaluateSurface(surf, Array(i - uStep, j))
				End If	
			End If
			
			Call Rhino.AddText(CStr(sgn), firstLine(k), 0.1)
			
			sgn = sgn + 1
			
			If sgn >= 4 Then
				sgn = 0
			End If
			
			mm = mm + 1
	Next
	
		n = n + 1
		ReDim Preserve ribArr(n)
	
		If (i<uDomain(1)-uStep*2) Then	
			rib = addRib(firstLine, hght)
			ribArr(n) = rib
		End If
		
		If(m>0) Then
			rib = addRib(secondLine, hght)
			n = n + 1
			ReDim Preserve ribArr(n)
	
			rib = addRib(firstLine, hght)	
			ribArr(n) = rib
		End If
		
	m = m + 2
	k = -1
	Next
	
	Call borders(uDomain, uStep, vDomain, vStep, hght)
	
	
	Call rhino.enableredraw(True)
End Sub

Function borders(uDomain, uStep, vDomain, vStep,hght)
	Dim i, j
	Dim pts : pts = Array()
	Dim k
	
	k = -1
	j = vDomain(0)
	For i=uDomain(0) To uDomain(1) Step uStep
		k = k + 1
		ReDim Preserve pts(k)
		
		pts(k) = Rhino.EvaluateSurface(surf, Array(i, j))
	Next
	Call addRib(pts,hght)
	
	k = -1
	j=vDomain(1)
	For i=uDomain(0) To uDomain(1) Step uStep
		k = k + 1
		ReDim Preserve pts(k)
		
		pts(k) = Rhino.EvaluateSurface(surf, Array(i, j))	
	Next
	Call addRib(pts,hght)
	
	k = -1
	i = uDomain(0)
	For j=vDomain(0) To vDomain(1) Step vStep
		k = k + 1
		ReDim Preserve pts(k)
		
		pts(k) = Rhino.EvaluateSurface(surf, Array(i, j))
	Next
	Call addRib(pts,hght)
	
	k = -1
	i = uDomain(1)
	For j=vDomain(0) To vDomain(1) Step vStep
		k = k + 1
		ReDim Preserve pts(k)
		
		pts(k) = Rhino.EvaluateSurface(surf, Array(i, j))
	Next
	Call addRib(pts,hght)
	
End Function


Function addRib(pts, height)

	Dim pt, pt2
	Dim pts2 : pts2 = Array()
	Dim k : k = -1
	
	For Each pt In pts
		k = k + 1
		
		ReDim Preserve pts2(k)
		pts2(k) = offsetPoint(pt, height)
	Next
	
	Dim firstLine, secondLine, rib
	
	firstLine = Rhino.AddPolyline(pts)
	secondLine =  Rhino.AddPolyline(pts2)
	rib = Rhino.AddLoftSrf(Array(firstLine, secondLine))
	
	'Call Rhino.UnselectAllObjects
	
	'Call Rhino.SelectObject(rib(0))
	
	'Call Rhino.Command (CStr("_UnrollSrf Explode=No Labels=No _Enter"), vbFalse)
	
	addRib = rib
	
End Function

Function offsetPoint(point, height)	
	Dim norm 
	Dim closestPt : closestPt = Rhino.SurfaceClosestPoint(surf, point)
	norm = Rhino.SurfaceNormal(surf, closestPt)
	norm = Rhino.VectorScale(norm, height)
	offsetPoint = Rhino.VectorAdd(norm, point)	
End Function