Graphics Language (Version 2.1)

This document defines the language interface to Version 2.1 of a device-independent graphics system intended to facilitate the use of graphics in the command and control environment. The system homogeneously supports graphics terminals of widely varying capability, configured with one or more different program running on separate computers connected via a C2 communications network. These include both calligraphic and bit-map displays as well as plotters. The set of graphics primitives defined here provides a core upon which device- independent application- tailored graphics packages can be built. Advanced graphics features such as color, shading, and input from multiple devices are supported in a manner that permits use of the same application program with devices not supporting those features. The graphics system performs the appropriate feature mapping to support the connected display device. For example, an application program may specify the color of a line segment. The system maps the specified color into some suitable color supported by the device or--in the case of a monochromatic display--into the single color of that device. An enquiry capability is also provided, permitting the application program to determine the characteristics of the connected display device and fully exploit all of its capabilities.