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The availability of inexpensive minicomputers and low cost digital/analog conversion equipment enables one to use interactive graphics in situations where such techniques were previously infeasible. The University of Tulsa is presently developing an interactive graphics package entitled BANDMARCH to assist the choreography of marching band drills. The graphics hardward consist of a 32K Interdata Model 70 minicomputer, a 5MB Diablo Disc system, a Tektronix 603 monitor with 256 × 256 point display provided by a pair of Detel 8 bit D/A converters. The program enables a band director who is most likely not computer oriented to prepare a routine in an existing language (About Face, Left Flank) and view the result of his ‘design’ in real time. The obvious interactive features of editing, cataloguing and accessing standard functions must be provided in a way that can be easily understood. T.U.'s BANDMARCH (not an acromym) provides such features. Common data structures in a relatively novel environment are a demonstration of the soundness of these techniques to an interactive graphics situation.

This paper discusses a system called DISPLAYTRAN that interpretively executes FORTRAN statements entered at a display console, allowing graphics users to perform unanticipated computations and to more easily debug graphics application programs. The relationships among the operating system, the display terminal, and the computing system are discussed, and the major components of this system are described. A command language, the FORTRAN IV subset, and the graphics language provided for users are presented. Internal operation of the graphic facility is outlined.

This article was prompted by the article written by Jon Meads in the Fall 1973 SIGGRAPH report. (1) A graphics package has been developed for use on Digital Equipment Corporation's GT40 and GT44 series of minicomputer-based graphics systems. Within the limitations of the machines, a package of graphics software was written to allow almost complete control of the display processor by a programmer using the language BASIC.

This paper describes the architecture of the micro-programmed processor which is the heart of the Adage GP/400 interactive graphics system, and discusses some of the factors which influenced its design.

Stand alone graphic systems and time-shared graphics provide different benefits to a user. The same is true of refresh graphics and storage displays. An operating system is described which supports these combined modes through the integration of graphics into the operating system. Realization of the role of the system, generality, and flexibility were the major factors in the development of the system. The result is a computer graphic system providing high-level interactive graphics at a relatively low cost.

A new two-dimensional graphics modeling program which has been fully implemented is introduced. Features include a generalized extendable graphics editor, an open-ended library of elements, a translator -macro processor for interface with a wide range of analysis routines, and on-line operating system control.

An interactive graphics space allocation system is described with which a designer at the console of an IBM 2250 can generate and edit preliminary building layouts.