The Implementation of the CGM as a GKS Metafile

Abstract

A major goal of recent computer graphics standards development has been a high degree of compatibility among standards. Two major standards have recently been adopted which provide a test case for demonstrating this goal: the Graphical Kernel System (GKS) and the Computer Graphics Metafile (CGM). This paper discusses the relationship between GKS and CGM from the perspective of implementation of an interface to CGM from GKS. The two models of graphics metafile represented by GKSM (GKS metafile) and CGM are compared. Areas of mismatch of functionality are analyzed and solutions to the functional mismatch are presented. Experiences with integrating CGM into the GKS environment are discussed, first, in terms of the generation of a CGM by a GKS implementation, then, in terms of interpretation of a CGM (not necessarily generated by a GKS implementation). Finally, there is a brief review of current work on extensions to CGM functionality which is intended to address some of the areas of mismatch between GKS and CGM.