Interaction diagrams: a visual language for controlling a visual program editor

A visual program editor is a graphics editor which has been specialized to support the creation of visual programs. Palette is a tool for constructing custom visual program editors from a generic editor and high-level specifications. One aspect of that customization is to specify the mapping from the actions of the user to the operations of the editor. Interaction diagrams are a visual notation for programming the direct manipulation aspects of the Palette editor. Interaction diagrams are based on finite state machines, with aspects of data-flow and objects, for defining overall control in the drawing interface. The author describes the initial version of the Indigo visual programming language, which is an implementation of interaction diagrams