Animation for on-line documents-an end-user system using object-oriented constraints

CBAD is designed to support mental abstraction of animation sequences and their components, freeing users from the need to deal with graphic representation, or implementation details and requiring no programming expertise. Using a metaphore based on movie directing, one creates animations in CBAD by assigning predefined animation actors with certain tasks. Complex behavior of predefined actors is achieved by establishing inter-actor relations, internally expressed as constraints maintained automatically by the system. Constraints are encapsulated and solved distributively