anchor.diff:  
   
           let sg =
  -            Glyph.geometry font '&' 
  +            Glyph.geometry font '@' 
                   |> Sg.ofIndexedGeometry
                   |> Sg.effect [
                       DefaultSurfaces.trafo |> toEffect
  
positive.code:             quad |> Sg.ofIndexedGeometry
  
  
          use font = new Font("Georgia", 1.0f)
  
  
  
  
negative.code: 
  
  
  
  
      let geometry (f : Font) (c : char) : IndexedGeometry =
          use path = new GraphicsPath()
          let size = 1.0f
  
          path.AddString(String(c, 1), f.FontFamily, int f.Style, size, PointF(0.0f, 0.0f), StringFormat.GenericDefault)
          
          
  
          let types = path.PathTypes
  