The 1974 manual of Pico, a graphics library for the Alto workstation developed at Xerox PARC. Callable from BCPL, it allowed to generate graphic output and handle input from a mouse or graphics tablet.

https://bitsavers.org/pdf/xerox/parc/memos/Newman_and_Sproull_-_PICO_Manual_197407.pdf

The manual mentions a planned Interlisp callable version but I found no trace of it. Maybe Pico evolved into or influenced DLISP.

https://dl.acm.org/doi/abs/10.1145/965103.807428

#retrocomputing #xerox #alto #interlisp

@amoroso
It's very worthwhile mentioning that this was authored by and Sproul, the year after they wrote the first graphics "bible":

"In 1973, Sproull and William M. Newman wrote Principles of Interactive Computer Graphics; a second edition was published in 1979. This was the first comprehensive textbook on computer graphics, and was regarded as the graphics "bible," until it was succeeded by Foley and van Dam's Computer Graphics: Principles and Practice."
(available online e.g. at https://archive.org/details/principlesofinter00newm )
https://en.wikipedia.org/wiki/Bob_Sproull
https://en.wikipedia.org/wiki/William_Newman_(computer_scientist)

Another interesting tidbit from Sproull wikipedia page:
"While working towards his B.A. in physics at Harvard College in 1967, Sproull met Ivan Sutherland. Together, they worked on head-mounted displays, which led the way for 3-dimensional virtual reality."

...and more.