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Item Haptic Simulation, Perception and Manipulation of Deformable Objects(The Eurographics Association, 2007) Magnenat-Thalmann, Nadia; Volino, Pascal; Bonanni, Ugo; Summers, Ian R.; Brady, A. C.; Qu, J.; Allerkamp, D.; Fontana, M.; Tarri, F.; Salsedo, F.; Bergamasco, Massimo; Karol Myszkowski and Vlastimil HavranThis tutorial addresses haptic simulation, perception and manipulation of complex deformable objects in virtual environments (VE). We first introduce HAPTEX, a research project dealing with haptic simulation and perception of textiles in VEs. Then, we present state-of-the-art techniques concerning haptic simulation and rendering, ranging from physically based modelling to control issues of tactile arrays and force-feedback devices. In the section on cloth simulation for haptic systems we describe techniques for simulating textiles adapted to the specific context of haptic applications. The section concerning tactile aspects of virtual objects shows how arrays of contactors on the skin can be used to provide appropriate spatiotemporal patterns of mechanical excitation to the underlying mechanoreceptors. Finally, the last section addresses the problem of developing suitable force feedback technologies for the realistic haptic rendering of the physical interaction with deformable objects, addressing the design of novel force feedback systems, innovative concepts for curvature simulation and control algorithms for accuracy improvement.Item SOME USEFUL BUT RATHER UNUSUAL GRAPHICAL PRIMITIVES(The Eurographics Association, 1981) Magnenat-Thalmann, Nadia; Thalmann, Daniel; Bergeron, Philippe; J. L. EncarnacaoThe MIRALIB library is a powerful graphical library which may be used with MIRA-2D, a graphical PASCAL extension as well as with the standard PASCAL language. MIRALIB includes figure algebra routines, figure measure functions, figure recognition predicates, image transformations as fitting or clearing and animation primitives. The most unusual primitives are presented with the help of a few examples.Item Real-time Inhabited Virtual Worlds and Interaction - interactive virtual worlds module(The Eurographics Association, 2006) Magnenat-Thalmann, Nadia; Papagiannakis, George; Egges, Arjan; Lyard, Etienne; Nadia Magnenat-Thalmann and Katja BühlerVirtual Worlds [MK94] and their concept of cyber-real space interplay invoke such interactive digital narratives that promote new patterns of understanding. However, the "narrative" and "interactive" part, which refers to a set of events happening during a certain period of time and providing aesthetic, dramaturgical and emotional elements, objects and attitudes ([NM00], [TYK01]) is still an early topic of research. Mixing such aesthetic ambiences with interactive virtual character augmentations [CMM*03] and adding dramatic tension has developed very recently these narrative patterns into an exciting new edutainment medium [LHM03]. With the interplay of a modern real-time framework for integrated interactive virtual character simulation, we can enhance the experience with full virtual character simulations.Item Course: Modeling Individualities in Groups and Crowds(The Eurographics Association, 2009) Donikian, Stéphane; Magnenat-Thalmann, Nadia; Pettré, Julien; Thalmann, Daniel; K. Museth and D. WeiskopfCrowds are part of our everyday life experience and essential when working with realistic interactive environments. Domains of application for such simulations range from populating artificial cities to entertainment, and virtual reality exposure therapy for crowd phobia. We mainly focus on real-time applications where the visual uniqueness of the characters composing a crowd is paramount. On the one hand, it is required to display several thousands of virtual humans at high frame rates. On the other hand, each character has to be different from all others, and its visual quality highly detailed. Variety in rendering is defined as having different forms or types and is necessary to create believable and reliable crowds in opposition to uniform crowds. For a human crowd, variation can come from the following aspects: gender, age, morphology, head, kind of clothes, color of clothes and behaviors.Item The Use of Finite Element Theory for Simulating Object and Human Body Deformations and Contacts(Eurographics Association, 1989) Gourret, Jean-Paul; Magnenat-Thalmann, Nadia; Thalmann, DanielThis paper presents a method for combining image synthesis and modeling based on a finite element method (FEM) to get realistic intelligent images. FEM is used for modeling both elastically and plastically deformations of objects, and impacts with or without penetration between deformable objects. The concept of deformable objects is applied to human flesh to improve the behavior of synthetic human grasping and walking. The paper also discusses the introduction of this method in an animation system based on the concept of "intelligent" synthetic actors with automatic motion control performed using A.I. and robotics techniques. In particular, motion is planned at a task level and computed using physical laws.Item Facial Modeling and Animation(Eurographics Association, 2003) Haber, Jörg; Terzopoulos, Demetri; Magnenat-Thalmann, Nadia; Blanz, VolkerIn this tutorial we present an overview of the concepts and current techniques that have been developed to model and animate human faces. We introduce the research area of facial modeling and animation by its history and applications. As a necessary prerequisite for facial modeling, data acquisition is discussed in detail. We describe basic concepts of facial animation and present different approaches including parametric models, performance-, physics-, and image-based methods. State-of-the-art techniques such as MPEG-4 facial animation parameters, mass-spring networks for skin models, and face space representations are part of these approaches. We furthermore discuss texturing of head models and rendering of skin and hair, addressing problems related to texture synthesis, bump mapping with graphics hardware, and dynamics of hair. Typical applications for facial modeling and animation such as speech synchronization, head morphing, and forensic applications are presented and explained.Item Key Techniques for interactive Virtual Garment Simulation(The Eurographics Association, 2005) Volino, Pascal; Magnenat-Thalmann, Nadia; Thomaszewski, Bernhard; Wacker, Markus; Ming Lin and Celine LoscosVirtual garment design and simulation involves a combination of a large range of techniques, involving mechanical simulation, collision detection, and user interface techniques for creating garments. Here, we perform an extensive review of the evolution of these techniques made in the last decade to bring virtual garments to the reach of computer applications not only aimed at graphics, but also at CAD techniques for the garment industry.Item Inhabited Virtual Heritage(Eurographics Association, 2001) Magnenat-Thalmann, Nadia; Chalmers, Alan; Thalmann, DanielTwo techniques depending on the interest – accuracy and precision of the obtained object model shapes, • CAD systems, medical application. – visual realism and speed for animation of the reconstructed models, • internet applications • Virtual Reality applications.Item Virtual Hip Joint: from Computer Graphics to Computer-Assisted Diagnosis(The Eurographics Association, 2009) Charbonnier, Caecilia; Schmid, Jérôme; Kolo-Christophe, Frank; Magnenat-Thalmann, Nadia; Becker, Christoph; Hoffmeyer, Pierre; K. Bühler and D. BartzOsteoarthritis (OA) is a major musculoskeletal disorder which causes are not always fully understood. Femoroacetabular impingements such as cam/ pincer cannot always explain observed OA in hips with normal morphology. This paper investigates the hypothesis of extreme repetitive movements as a source of cartilage degeneration. We present a clinical study conducted with professional ballet dancers and a methodology to perform functional simulations of the hip joint in extreme postures. Throughout the process, various computer graphics techniques are used, like motion capture, 3D body scanning and physically-based models. In addition to accelerate and strengthen some tasks, these techniques strongly participate in the clinical understanding of OA related to motion. Preliminary results have indeed shown a significant correlation between the location of impingements and radiologically observed damage zones in the labrum cartilage.Item Towards the Virtual Physiological Human(The Eurographics Association, 2007) Magnenat-Thalmann, Nadia; Gilles, Benjamin; Delingette, Hervé; Giachetti, Andrea; Agus, Marco; Karol Myszkowski and Vlastimil HavranThe objective of this tutorial is to train students and researchers in the various domains involving the modelling and simulation of the human body for medical purposes. Human body representations have been used for centuries to help in understanding and documenting the shape and function of its compounding parts. Nowadays, medical acquisition devices especially medical scanners are able to produce a large amount of information, such as highresolution volumes, temporal sequences or functional images, more-and-more difficult to analyse and visualise. In other words, we measure much more than we understand. In this context, higher-level information such as anatomical and functional models is increasingly required to support diagnosis and treatment. Three levels of complexity can be distinguished (geometry, function and control) where modelling and simulation methods take place. In this tutorial, we will present the current research issues towards the patient-specific reconstruction of virtual models and their functional simulation. We will focus on the computer graphics aspects involved in medical modelling/ simulation: deformable model-based segmentation, mesh optimisation, data fusion, interactive mechanical simulation, cost-efficient visualisation, etc. Examples will be given in the musculoskeletal, cardiac and neurological domains. All speakers are partners of the EU project "3D Anatomical Human" led by MIRALab - University of Geneva.