Interactive graphics for structural chemistry

• Published in: Computers & chemistry 1977, Vol.1 (2), p.75-78
• Main Authors: Glick, Milton D., Anderson, Thomas J., Butler, William A., Corey, Eugene R., Srodawa, Ronald J.
• Format: Article
• Language: English
• ISSN: 0097-8485
• DOI: 10.1016/0097-8485(77)80002-8

An interactive graphics display system that allows users to display and to alter monoscopic or stereoscopic projections of crystallographic or quantum mechanical models and to communicate with a central computer facility is described. The display panel is a digital write-only memory plasma panel with a grid of 512 × 512 points; a mini-computer is used to drive the panel. The molecular graphics mode software has been written in BASIC with the addition of graphics—primitives that simplify the display of geometric figures. The communication mode software has been written in an assembler language routine that may be called from BASIC. The ASCII character code is presently used for communication through a 1200 baud modern to the central computer facility. Communications are effected in two modes. (1) Information from local files and the keyboard flow to the central facility and from there back to the plasma tube and local files; or (2) the graphics system and central facility appear as a two processor computer with programs cooperatively executing simultaneously on both central processors. A description of a minimal and expanded system is included. The relatively low cost of such a system suggests it is applicable to a number of limited budgets. The simplicity of the system makes it a valuable tool for teaching and research in crystallography, quantum mechanics, and topics of general chemical interest.