A CAD system in APL
Uday G. Gujar, Joseph W. P. So · ACM SIGAPL APL Quote Quad · 1987
A two-dimensional Computer Aided DEsign Tutorial System (CADETS) has been designed and implemented and is reported in this paper. The graphics screen is divided into five windows. The main, and the largest, window is used for graphics; the others are used for user communication which is achieved through a structure of well defined menus and the system messages. There are currently eleven ways to create a point, thirteen ways to create a line segment, ten ways to specify a circular arc, several functions to generate common geometric objects such as triangles, rectangles, polygons, conics and ten fonts to write labels. Once created, the user may pick the geometric entities in the current model for inquiry, transformation or deletion through a series of selection menus. Translation, scaling, rotation, and mirroring is facilitated by transformation functions. Model file management functions enable the user to store the created geometric models on an auxiliary device and retrieve and manipulate them with options to move, copy or duplicate the transformed entities. The power of CADETS is further enhanced by the introduction of layers. This facility enables the user to view and draw each individual layer independently or to view selected layers simultaneously.