Graphics server and action language interpreter greatly simplify the composition of a graphical user interface

A new control system based on a distributed computing environment is gradually installed at BESSY, a 800 MeV storage ring dedicated to the generation of synchrotron light in the VUV and soft X-ray region. The new operator consoles are large high resolution, bitmap oriented color graphic screens with mouse and keyboard. A new graphical user interface has been developed with a user interface management system. A graphics server encapsulates completely representational aspects, mediates between user interactions and application variables and takes care of a consistent state of graphical and applicational objects. Graphical representations, semantics of user interactions and interpreter instructions are defined in a database written in a simple and comprehensible user interface definition language. (R.P.) 7 refs.; 5 figs