Computers & Graphics 27 (2003) 71–82 Technical section Interaction-free dressing of virtual humans Arnulph Fuhrmann a, *, Clemens Gro a , Volker Luckas a , Andreas Weber b a Fraunhofer-Institut f . ur Graphische Datenverarbeitung Fraunhoferstr. 5, 64283 Darmstadt, Germany b Institut f . ur Informatik II, Universit . at Bonn R . omerstr. 164, 53117 Bonn, Germany Abstract We describe an interaction-free method for a geometric pre-positioning of virtual cloth patterns with human 3D scans. Combined with the following physically based sewing simulation, a fully automated dressing of virtual humans becomes possible. This reduces the time needed for dressing virtual humans by eliminating the time needed for the interactive placement of the cloth patterns in previous methods, where the patterns have to be pre-positioned by user interaction. The result of our pre-positioning method is computed in less than 0:3 s CPU time for various examples on current PCs and designed to converge efficiently in the simulation step afterwards. r 2002 Elsevier Science Ltd. All rights reserved. Keywords: Cloth modeling; Physically based modeling; Optimization for animation 1. Introduction Modeling clothing and textiles has become a major topic in computer graphics research; see e.g. [1] for a survey up to 1996, [2] for a collection of some landmark papers up to 2000, [3] for a recent textbook, or [4,5] for some research papers from the last year. On the application level, virtual clothing for various kinds of virtual actors has become a reality [6,7]. This has become possible because major advances have been achieved for the simulation times of virtual clothing. This involves simplified cloth models such as the ones used in [8,9], but also more accurate models such as the ones used in [10,4]. A comparison and survey of both approaches can be found in [11]. Also, the area of collision detection and response for cloth, another prerequisite for the clothing of virtual actors, has been the topic of intense research [8,12,7,13,3]. For the initial manipulation of the clothing patterns— placing them around a virtual actor and sewing them together—interactive techniques have been used [14,3]. While interactive manipulation of the patterns is a sufficient technique for some applications, such as virtual actors, it is not acceptable in other areas like a virtual clothing boutique, in which customers want to see the fit of several pieces of clothing on their virtual twins, i.e. figurines obtained from measurement data or 3D scans of individual customers. This boutique can reside in a real shop or even be realized as an internet application. In the latter case the customer may try on garments from home. Major prerequisites for such a scenario in a virtual boutique exist. Methods of obtaining the geometric surface data of real people by 3D-scanning technologies are well established. Also large collections of CAD data of the patterns of ‘‘real clothing’’ exist, which can be stored in standard databases together with information on sewing, texture, material properties, etc. However, no system has been described up to now that would allow the fully automated simulation of clothing on an individual figurine by taking the clothing information out of a database without requiring any user interaction. The manipulation of the patterns before sewing them together at the right places near a figurine required the interaction of a user in all systems that have been described in the literature. After the patterns are sewen together, the various physically based simulation systems then allow an automated simulation *Corresponding author. Tel.: +49-6151-155640; fax: +49- 6151-155139. E-mail address: afuhr@igd.fhg.de (A. Fuhrmann). 0097-8493/03/$-see front matter r 2002 Elsevier Science Ltd. All rights reserved. PII:S0097-8493(02)00245-5