dc.description.abstract | Conformance testing for the Programmer’s Hierarchical Interactive Graphics System (PHIGS) standard presents certain novel difficulties, especially the indirect effect of many functions, and the inaccessibility to the program of visual effects. The PHIGS Validation Tests (PVT) incorporate several innovative design features in order to address these difficulties. The model of deductive inference suggests ways to organize a system as logically complex as the PVT. This complexity makes the use of certain database concepts quite valuable in allowing users to navigate within the system. The problem of inaccessible effects can be addressed by careful design of the user interface, so as to minimize the subjectivity and operational difficulty inherent in testing such features. Subjectivity is minimized by posing short simple questions to the operator, in which the expected answer is randomized. Several design features enhance ease of use, including a customizable interface, self-explanatory displays, and automatic capture of results. | en_US |