Computer graphics
You read R.C.M.?
It is now exactly spelled out, but same methods were used in printing on wings for Gollywock in December 2001 issue.
Used to have a picture of a Super Sinbad with computer plotted LiteSpan (more difficult, and non-erasble) at the site for Bob Holman plans. Ask him for picture if it cannot be pulled up anymore. His site has dead spots in it on occasion to certain viewers, and his nephew is in hospital, so may be a while before it gets fixed.
Wm.