A multi-layer graphic model for building interactive graphical applications

In this article, we present a model based on multilayer graphics for building interactive graphical applications. With this model, a variety of components of an interactive graphical editor (transient objects like the selection rectangle, selected objects, grids, cursors), as well as the handling of input events, acquire a clearer status. We show how an interactive graphical application can use layered graphics in a simple and effective way to describe direct manipulation, some graphic constraints and events handling using various input devices. By giving a clear status to abstract elements of an interactive application, the model helps to describe a significant part of the dynamic aspect of the interaction.