Half-tone perspective drawings by computer

In recent years, the sheer increase in demand for the graphic presentation of three-dimensional objects has almost overwhelmed conventional facilities; that is, designers, draftsmen and especially engineering artists. For example, it is important for a designer or architect to quickly describe a three-dimensional object and view it immediately; not as an endless set of engineering drawings, but as if he were viewing the three-dimensional object itself. He should be able to take a distant look at a complicated object, and then view, in detail, any subsection of the object. In other words, he would like to quickly and cheaply simulate and view the thing he is designing.