Simulation and Application of Virtual Reality in Architectural Design?YANG Yi( Faculty of Architectural Engineering,Kunming Unviversity of Science and Technology, Kunming 650224, China)Abstract: The development of internet and Virtual Reality technology raises a new concept ? VirtualArchitecture and Virtual City ? in the field of architecture and CAAD. After analyzing a lot of simu? lation and application of Virtual Reality in architectural design, this paper indicates that an integratedVR world builder and environment is critical to the VR development, and new concepts and meth?ods of CAAD have been put forward.Key words:virtual reality; CAAD; simulation and applicationCLC number:TU18? ? Document:A ? ? Article:1007- 855X( 2002) 03- 094- 030? IntroductionComputer simulation technologies have already been applied to studying the built environment such as ar? chitecture and urban space for years1. T he purpose of simulation is to better understand the prospective cre? ation or changes before the physical implementation through various mechanisms. The lately developed virtual reality ( VR) technology, known as?a simulated interactive environment?, even provides promising character? istics such as immersivity,interactivity,and fidelity 2. Furthermore,the more profound impact on cy? berspace is through internet browsers to view VR models created by virtual reality modeling language ( VRML) . T herefore, it is critical to explore the potential uses of VR in architectural design. The following sections will describe the application of virtual reality in architectural design and how to model the architectural objects and behaviors.1? The Applacation and Significance of Vitual Reality in Architectual DesignVirtual Reality ( VR) , a very advanced human- computer interaction tool3, provides diversified media for visually, aurally, and interactively experiencing activities and behaviors conducted in the cyberspace. De? sign taught in this fashion will be very effective, and professional design projects done in VR will have great protential for communication and presentation 4. Applying this tool to design offers four advantages over other CAD system. First, it enables navigation performing in full scale to create the sense of immersion and reflection of the seeing- as. Second, it allows the creation, modification, and editing of three- dimensional object in a virtual space. T hird, design can be mod? ified and viewed simultaneously inside or outside of the generated model to obtain the best design products. Fourth, the entire design process can be recorded and played back 5. T raditionally, architectural design begins with an idea in mind; then, either a two- dimensional concept第 27 卷 第 3 期昆? 明? 理? 工? 大 ? 学 ? 学? 报Vol. 27? No.3 2002 年 6 月Journal of Kunming University of Science and TechnologyJun. 2002?Received date:2001- 01- 11; ? Foundation: The National Science Foundation of the board of science The National Science Foundation of the board of Education of Yunnan province ( No. 279942068) ;? ? ? ? Biography:Yang yi, male, born in 1970, post graguate of Doctor degree in T ongji University. Main Research: Architectural design.is sketched on paper, or a three- dimensional model is constructed to visually perceive the form and to evalu? ate the design product. A designer will rarely design in full scale. The convention of sketching in paper and constructing miniature models is very much culture- bound. Even though the conventional methods provide a means for cultivating ideas, they set up certain limits on stimulation and inspiration. Because designers cannot project themselves into the space in the same way as they are physically existing, the experience of seeing- as and reflection in- action 6is limited, and the scope of design thinking is narrowed. If a medium provides de? signers with an opportunity to see design interactively, a sense of projection into design will be generated. In the design profession, diversity will broaden personal vision, enrich mental images, and stimulate multidirec? tional thinking. All these are likely to improve design quality. Furthermore, diversified media applied in de? sign will broaden thinking, change the design process, and enhance creativity. Any design medium that culti? vates diversity can be seen as an appropriate future design tool.2? The Simulatoin of Virtual Reality in Architectual Design2. 1? Modeling Architectural Object and Behaviors An object is considered as a single artifact, and a scene consists of a group of related objects. Two basic approaches of creating objects or scenes are: ( 1) to translate from other formats to VR models, or ( 2) to use existing VR modelers to create objects. Because VR is real- time rendered without setting path, and is differ? ent from computer animation, the complexity of objects is critical to its performance. Most current modelers have limitation of number of polygons that can be used for optimizing the performance7. T he