This paper presents an efficient way to provide a graphical interactive visualization to a non-interactive existing object oriented application. Assuming that the initial application uses an “Abstract Factory” pattern (GoF87) in order to create new objects, our aim is achieved by using the PAC-Amodeus model and extending the existing objects to create intermediate components, using object oriented techniques: inheritance, polymorphism and dynamic binding, using the `Proxy' pattern (GoF207). Although our field of interest is physical and behavioral simulation, the techniques developed in this paper can be applied to any non-interactive object oriented existing kernel. Then, we present a complete simulation example `Bugs life' to illustrate the use of our method. Finally, we point out the limits of our approach, and we suggest new directions for further work.