> I suppose Bresenham had his reasons. Why not ask him. He's very approachable. Jack Bresenham bresenhamj@exchange.winthrop.edu I exchanged emails with him a year or so ago after discovering (many years after the event) that I had "invented" his method some 11 years after he did :-) Russell McMahon -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads