Computer-Aided Civil and Infrastructure Engineering 25 (2010) 55–68 Interactive Graphical Representation for Collaborative 3D Virtual Worlds Ning Gu ∗ School of Architecture and Built Environment, University of Newcastle, Australia & Jerry Jen-Hung Tsai Department of Art Creativity and Development, Yuan Ze University, Taiwan Abstract: Three-dimensional (3D) virtual worlds have the potential to make a major impact on global de- sign teams by providing an online place that supports distant design activities without designers being physi- cally present. To accommodate designing in 3D virtual worlds for the architecture, engineering, and construc- tion (AEC) domain, there is an urgent need for the development of a representation system applicable in conceptual design and multi-disciplinary design. Ex- tended from Qualitative Archi Bond Graphs (QABGs) that are developed as qualitative unified representations for buildings, this article presents and demonstrates an interactive graphical representation for collaborative de- sign in 3D virtual worlds. The representation supports multiple design representation subsystems and their in- teractions that enable designers to better facilitate design collaboration in 3D virtual worlds. 1 INTRODUCTION In the architecture, engineering, and construction (AEC) domain, the ever increasing globalization results ∗ To whom correspondence should be addressed. E-mail: ning.gu@ newcastle.edu.au. in large projects that require global design teams to collaborate across different geographical locations and time zones, which often demands additional time and financial inputs in coordinating and relocating human and design resources. Three-dimensional (3D) virtual worlds have the potential to make a major impact on global design teams by providing an online place that supports distant design activities without designers be- ing physically present. Supporting a wide variety of hu- man activities online, 3D virtual worlds are networked environments designed using the place metaphor. 3D virtual worlds distinguish themselves from other net- worked technologies by having place characteristics. They are not just another communication tool but func- tional online places, where various human activities ranging from business, education, and social interaction to entertainment are supported. Designers use representations to communicate and collaborate on design projects. Digital representations for building designs are often developed for specific building subsystems, for instance, AutoCAD for ar- chitecture and DDS-CAD for hydraulics and electric- ity. More importantly, most digital representations, for example, architectural drawings and conventional CAD models usually only address the final design C  2009 Computer-Aided Civil and Infrastructure Engineering. DOI: 10.1111/j.1467-8667.2009.00613.x