VNC.RFBDrawing.UpdateDecoders.RREBaseDecoder.drawRectangle Function
the difference in the CoRRE and RRE Protocol is in the method to encode a rectangle

Protected void drawRectangle (System.Drawing.Color, DrawingSupport.DrawingObject)
  Type Name Description  
    System.Drawing.Color foreCol    
    DrawingObject drawDest    
  Return Description  
    void