anchor.diff:                  
           for (pts, att) in regions do
               let contour = LibTess.closed pts
  -            for i in 0 .. contour.Length - 1 do contour.[i].Data <- att.[i]
  +            for i in 0 .. contour.Length - 1 do contour.[i].Data <- att.[i % att.Length]
               t.AddContour(contour)
   
           let combine (pos : Vec3) (data : obj[]) (weights : float[]) =
  
positive.code:                 
          for (pts, att) in regions do
              let contour = LibTess.closed pts
              for i in 0 .. contour.Length - 1 do contour.[i].Data <- att.[i]
              t.AddContour(contour)
  
          let combine (pos : Vec3) (data : obj[]) (weights : float[]) =
  
negative.code:                 
          for (pts, att) in regions do
              let contour = LibTess.closed3 pts
              for i in 0 .. contour.Length - 1 do contour.[i].Data <- att.[i % att.Length]
              t.AddContour(contour)
  
          let combine (pos : Vec3) (data : obj[]) (weights : float[]) =
  