Report Number: CS-TR-68-114
Institution: Stanford University, Department of Computer Science
Title: Calgen - an interactive picture calculus generation system
Author: George, James E.
Date: December 1968
Abstract: A sub-set of the Picture Calculus was implemented on the IBM
360/75 to experiment with the proposed data structure, to
study the capability of PL/1 for implementing the Picture
Calculus and to evaluate the usefulness of drawing pictures
with this formalized language. The system implemented is
referred to as Calgen.
Like many other drawing proggrams, Calgen utilizes a graphic
display console; however, it differs from previous drawing
systems in one major area, namely, Calgen retains structure
information. Since the Picture Calculus is highly structured,
Calgen retains structure information, and only scope images
where convenient; further, these scope images saved may be
altered by changing the structure information. The only
reason scope images are saved by Calgen is to avoid
regeneration of a previously generated picture.