-Runscript
(Option Explicit
'Script written and copyrighted by Jaroslaw Bieda	
'Script version August 19, 2007 6:10:31 PM

Call RandomPointsOnSurf()
Sub RandomPointsOnSurf()
	
	Dim strSurface, strSurfaceShrunk
	
	Dim arrPoints() 
	Dim arrCurves, idCurve
	Dim dblCrvDist : dblCrvDist=0
	Dim arrDomU, arrDomV
	Dim t(1), pt, strPoint
	Dim a, m, j
	Dim idDistTest
	Dim intM : intM = 0 'level of point count match
	Dim blnSkip : blnSkip = vbFalse 'skipping regenerating points while MinDist=0 and switching strMatch levels
	
	strSurface = Rhino.GetObject("Select surface to generate random points on",8)
	If IsNull(strSurface) Then Exit Sub

	arrCurves=Rhino.GetObjects("Select edge curves ( ENTER if none )",4)
	Dim l : l=1
	If Not IsNull(arrCurves) Then l=0

	
	Call Rhino.EnableRedraw(vbFalse) 'shrinking surface to speed up the process
	strSurfaceShrunk=Rhino.CopyObject(strSurface)  
	If Rhino.IsSurfaceTrimmed(strSurfaceShrunk) Then Rhino.ShrinkTrimmedSurface(strSurfaceShrunk)
	arrDomU = Rhino.SurfaceDomain(strSurfaceShrunk, 0)
	arrDomV = Rhino.SurfaceDomain(strSurfaceShrunk, 1)
	Call Rhino.DeleteObject(strSurfaceShrunk)
	Call Rhino.EnableRedraw(vbTrue)
	
	If Not IsArray(arrDomU) Or Not IsArray(arrDomV) Then Exit Sub
	
	'OPTIONS
	Dim strResult, arrOptions() : ReDim arrOptions(5-l)
	Dim intQuantity : intQuantity = 10 'Initial points number
	Dim dbDist : dbDist=0
	Dim strMatch : strMatch="Disabled"
	
	Do
		arrOptions(0)="Randomize"
		arrOptions(1)="PointCount_" & intQuantity
		arrOptions(2)="MinPtDist"
		If dbDist<1 And dbDist>0 Then arrOptions(2)="MinPtDist_between_0_and_1"
		arrOptions(3)="MatchPointCount_" & strMatch
		arrOptions(4)="CurveMinDist"			
		arrOptions(5-l)="CREATE"
			
		
		If blnSkip=False Then	
			ReDim arrPoints(0) : j=0
			'GENERATING RANDOM POINTS
			Call Rhino.EnableRedraw(vbFalse)
			For a = 1 To intQuantity
				For m = 0 To intM '-loop for iterations for point count match	
					Do
						t(0) = arrDomU(0) + (((arrDomU(1) - arrDomU(0))*Rnd)) 
						t(1) = arrDomV(0) + (((arrDomV(1) - arrDomV(0))*Rnd)) 
						pt = Rhino.EvaluateSurface(strSurface, t)
						If Rhino.IsPointOnSurface(strSurface,pt) Then Exit Do
					Loop
				
					strPoint = Rhino.AddPoint(pt) 
					'testing for existing points withing given minimum distance		
					If dbDist > 0 Then
						If IsArray(Rhino.SelectedObjects) Then
							For Each idDistTest In Rhino.SelectedObjects	
								If FastDistance(pt,Rhino.PointCoordinates(idDistTest)) < dbDist Then
									Rhino.DeleteObject(strPoint)
									Exit For
								End If
							Next	
						End If
					End If

					'testing distance to curves
					If l=0 And dblCrvDist>0 And Rhino.IsObject(strPoint) Then
						For Each idCurve In arrCurves
							If FastDistance(Rhino.PointCoordinates(strPoint),Rhino.EvaluateCurve(idCurve,Rhino.CurveClosestPoint(idCurve,Rhino.PointCoordinates(strPoint)))) < dblCrvDist Then
								Rhino.DeleteObject(strPoint)
								Exit For
							End If
						Next
					End If

					If Rhino.IsObject(strPoint) Then
						ReDim Preserve arrPoints(j)
						arrPoints(j)=strPoint
						j=j+1
	   				 Exit For
					End If
				Next
									
				Call Rhino.SelectObject(strPoint)
				'process percentage and points generated	
				Call Rhino.Prompt("Generating points... "&CStr(Int((100*a)/intQuantity))&"% | Generated " & CStr(UBound(arrPoints)+1)&" points. Press ESC to cancel")
				'refresh every 10%
				If a Mod (intQuantity/10) = 0 Then			
					Call Rhino.EnableRedraw(vbTrue)
					Call Rhino.EnableRedraw(vbFalse)
				End If
				
			Next
			Call Rhino.Print("Generated " & CStr(UBound(Rhino.SelectedObjects)+1)&" points...")	
			Call Rhino.EnableRedraw(vbTrue)
		End If
		
		'OPTIONS
		strResult = Rhino.GetString("Generate random points on surface","CREATE",arrOptions)
		Select Case Left(UCase(strResult),2)	

			Case "CU"
				dblCrvDist=Rhino.GetReal("Minimum distance from curve?",dblCrvDist,0)
				If IsNull(dblCrvDist) Then dblCrvDist=0
				Call Rhino.DeleteObjects(Rhino.SelectedObjects)
				If dblCrvDist>0 Then blnSkip=False
			
			Case "CR"
				Exit Do
				
			Case "PO"
				intQuantity = Rhino.GetInteger("Number of points to generate",intQuantity,1)
				Call Rhino.DeleteObjects(Rhino.SelectedObjects)
				
			Case "RA"
				Call Rhino.DeleteObjects(Rhino.SelectedObjects)
					
			Case "MI"
				dbDist=Rhino.GetReal("Minimal point to point distance",dbDist,0)
				Call Rhino.DeleteObjects(Rhino.SelectedObjects)
				If dbDist>0 Then blnSkip = False
				
			Case "MA"  ' setting the level of point count match while minimal distance is defined
			
				If dbDist=0 Then blnSkip = vbTrue
				
				strMatch=Rhino.Getstring("Select point count match attempt level",strMatch,Array("Disabled","Low","Med","High","Max"))
				Select Case Left(UCase(strMatch),2)
					Case "DE"
						intM = 0
					Case "LO"
						intM = 10
					Case "ME"
						intM = 50
					Case "HI"
						intM = 100
					Case "MA"
						intM = 300
					Case Else
						strMatch="Disabled"
						intM=0
				End Select
				If Not blnSkip=True Then Call Rhino.DeleteObjects(Rhino.SelectedObjects)
					
			Case Else 
				Call Rhino.DeleteObjects(Rhino.SelectedObjects)
				Exit Sub
							
		End Select
				
	Loop
			
	Call Rhino.Command("!_Group")

End Sub

Function FastDistance(byref P1,byref P2)
	FastDistance=Sqr((P1(0)-P2(0))*(P1(0)-P2(0))+(P1(1)-P2(1))*(P1(1)-P2(1))+(P1(2)-P2(2))*(P1(2)-P2(2)))
End Function)