A Framework to Generate Heterogeneous Collaborative Web Environments

A Collaborative Virtual Environment, CVE, is a computer-based virtual space that supports collaborative work and social interplay. In a 3D CVE, a “hosting” 3D world is the necessary ingredient: within it, users, provided with graphical embodiments, called avatars, that convey their identity (presence, location, movement, ..) can meet and interact with other users, with agents, or with virtual objects.

Even if  graphics hardware and 3D technologies are rapidly evolving  and the increased internet connection speed allows to share amount of data and information between user geographically distributed, the development of networked three-dimensional applications is still complicated and demands expert knowledge. Though some collaborative Web 3D technologies and applications had already been developed, most of them are concerned especially to offer an high level realistic representation of the virtual world as increasing the level of detail would mean to increase the “virtual presence” sense in the 3D world; at the same time they don’t support from one hand an high level, non-expert authoring process, from the other the concept of programming flexibility and of component reuse is rarely taken into account.

In my thesis, we advocate the need of drastically simplify authoring and personalization phases through  formal description of the interaction’s sets as well as of the  behavioral features and rules, that we call “collaborative metaphors”, in a component oriented fashion to drive collaboration among users in the specific way a designer is intended to do. As result of previous considerations we present WebTalk04 (WT04), a declarative 3D component framework based on XML documents describing not only the environment formal structure of the virtual world were the action take place but also the complex interaction  set  of rules that control interactions between users and world objects used to stimulate certain kind of collaboration, thus effectively help fast prototyping and an easy building up of such collaborative applications. The WT04 framework also provide a runtime 3D rendering engine fully configurable through XML in order to easily modify virtual world settings as well as collaborative interaction rules thus allowing to control independently geometries, behaviors and contents, assigning to different developer (i.e software dev. , content dev. , graphics dev. , session designers) different task.

Main innovative features of the proposed framework are:

• Decouple all phases of the authoring process
• Easily define and compose virtual sessions in a component oriented fashion
• Drive and control interaction among user to stimulate specific kinds of collaboration

Moreover, event thought Collaborative Virtual Environments are one of the most successful application in the field of Computer Supported Collaborative Workgroup (CSCW), their support and working environment has often been relegated to desktop systems without regarding of recent spread of smart mobile devices and wireless networks. In this work, we also present the extension of the WebTalk framework to support in a flexible way both stationary and mobile systems.  We explore the use of heterogeneous collaboration thought a software architecture, running on mobile devices compatible with J2ME, able to configure itself on the basis of a XML declaration representing workspace and interaction rules shared with the 3D  stationary users.