As we move more complex algorithms to parallel computers we have found it more and more necessary to gain understanding of the behavior of a program through application-specific animation. Although the extra level of insight obtainable through program animation is very great, the effort required is similarly large. Typically considerable ``extra'' programming must be done, often requiring expertise in graphical programming. In an effort to make it much easier to application programmers to incorporate program animation into their programs, we are developing a system we call PADL (Program Animation Display Language).
PADL interprets a logfile (in the same format as that read by upshot which is evolving to be consistent with the format described in [Worley 1992]), together with a simple text file describing graphical actions to be taken for each event in the logfile. The research objective in this project is to develop a set of animation primitives expressive enough to to allow a programmer to assemble a custom-designed meaningful animation for his application, while at the same time compact enough to be easy to implement and efficient. Currently we are slowly expanding the set of primitives available.