Editable Graphical Histories

Graphical interfaces typically provide their users with little idea of a session’s history, except insofar as it is reflected in the current state of the sytem. If undo and redo commands are provided, they are often the only way to review the actions performed, cycling through them in sequence. We allow the user to review and modify the actions performed with a graphical interface. We have designed a testbed system that creates a series of automatically generated panels that depict in chronological order the important events in the history of a users session with Chimera, a graphical editor. Our system heuristically determines the contents of each panel and the actions that it illustrates. The user can scroll through the sequence of panels, reviewing actions at different levels of detail, and selectively undoing, modifying, and redoing previous actions.