Virtual Urban Environments are an important content to the Virtual Reality Systems used in applications such as urban planning and management, virtual tourism, cultural heritage and education. This kind of virtual environments make available three-dimensional models that replicate the particular urban environments, allowing the attainment of high levels of detail and visual fidelity and thus being a natural metaphor for interaction. The tasks developed in urban environments often demand for cooperative work between different professionals, whom could greatly benefit from a collaborative tool, similar to the Wiki concept. A “Wiki” is collaborative software that allows cooperative edition of documents, without the need a supervision process.
This project aims at the development of a collaborative VR (Virtual Reality) system that provides a more natural and intuitive interface to supply diversified services upon urban environments – a 3D Wiki for urban environments. These services shall contemplate citizenship activities, entrepreneurship activities, promotion of the natural and cultural heritage and support of the cooperation and data sharing among citizens.

The 3D Wiki for urban environments, proposed in this project, requires virtual environments, composed by three-dimensional models of the objects tha populate them. In order to increase the effectiveness of the participation of users, it shall include an immersive virtual environment where services are provided and cooperative work is supported. However, generating models of urban environments poses a great number of Computer Graphics problems, as the amount of information needed to create realistic models increases with the scene size and complexity. Although some models have been created by individual modelling of each element in the urban environment, semi-automatic methods have proven to be much more effective by reducing the duration, the cost and the allocation of human resources. Data amplification can be achieved based on mathematical tools such as geospatial L-systems from an initial set of urban data. This process is regulated by the definition of a set of production rules that capture the knowledge about these urban environments. This technology is being develop by this research team, and will be further enhanced to support the 3DWikiU system.

Expeditious modelling of virtual urban environments requires a high level of interactivity, leading to the need for a set of specific tools for the authoring of the modelling processes. These tools shall provide authoring by example: as the user defines production rules, it is possible to visualize their effect on a specific initial object.

Information on urban environments is generally scattered and structured in different ways. This project aims at the development of a unified information model that adapts to the concepts and features of urban reality, and a set of tools that enables the expeditious mapping of existing data sources to the defined model.