Open Issues for the development of 3D Multimodal User Interfaces from an MDE perspectiv

Given its current state of the art, Model-Based UI Development (MBDUI) is able to fulfill the major requirements of desktop and mobile applications, such as form-based user interfaces that adapt to the actual context of use. More recent research deals with the development of 3D interactive multimodal environments. Though user-centered design is more and more driving the design of these environments, less attention is devoted to the development proc-esses than to interactive tools supporting isolated phases in the realization process. In this paper we describe our findings when considering model-based development of 3D multimodal applica-tions in the context of model-driven engineering. We concentrate on the requirements of such a process, the models being used and the transformations that are able to guide or even automate part of the development process for the envisioned applications. We con-clude with some open issues that have been discovered.