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Item Simulation of Facial Muscle Actions Based on Rational Free Form Deformations(Blackwell Science Ltd and the Eurographics Association, 1992) Kalra, Prem; Mangili, Angelo; Thalmann, Nadia Magnenat; Thalmann, DanielThis paper describes interactive facilities for simulating abstract muscle actions using Rational Free Form Deformations (RFFD). The particular muscle action is simulated as the displacement of the control points of the control-unit for an RFFD defined on a region of interest. One or several simulated muscle actions constitute a Minimum Perceptible Action (MPA), which is defined as the atomic action unit, similar to Action Unit (AU) of the Facial Action Coding System (FACS), to build an expression.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 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 Combined Direct and Inverse Kinematic Control for Articulated Figure Motion Editing(Blackwell Science Ltd and the Eurographics Association, 1992) Boulic, Ronan; Thalmann, DanielA new approach for the animation of articulated figures is presented. We propose a system of articulated motion design which offers a full combination of both direct and inverse kinematic control of the joint parameters. Such an approach allows an animator to specify interactively goal-directed changes to existing sampled joint motions, resulting in a more general and expressive class of possible joint motions. The fundamental idea is to consider any desired-joint space motion as a reference model inserted into the secondary task of an inverse kinematic control scheme. This approach profits from the use of half-space Cartesian main tasks in conjunction with a parallel control of the articulated figure called the coach-trainee metaphor. In addition, a transition function is introduced so as to guarantee the continuity of the control. The resulting combined kinematic control scheme leads to a new methodology of joint-motion editing which is demonstrated through the improvement of a functional model of human walking.Item An Integrated System for Modeling, Animating and Rendering Hair(Blackwell Science Ltd and the Eurographics Association, 1993) Daldegan, Agnes; Thalmann, Nadia Magnenat; Kurihara, Tsuneya; Thalmann, DanielThere are basically four problems to solve in order to produce realistic animated synthetic actors with hair: hair modeling and creation, hair motion, collision detection and hair rendering. This paper describes a complete methodology to solve these basic four problems. We present how hair styles may be designed with our Hair Styler module. Then we survey the animation model and emphasize a method of collision processing. Finally, we explain how hair may be rendered using an extension of a standard ray-tracing program. We also show applications of our synthetic actors with various hair styles and different styles of mustaches and beards.Item The Problematics of Human Prototyping and Animation(Blackwell Publishing Ltd and the Eurographics Association, 1989) Magnenat-Thalmann, Nadia; Thalmann, DanielSeveral ideas and experiments are presented for the creation and realistic animation of three-dimensional scenes involving human beings conscious of their environment. The various approaches should allow the intelligent creation of human beings using prototypes and generate their animation based on mechanics, artificial intelligence and robotics. This paper discusses the problems involved in three major steps of the simulation of human beings: the creation of the human shapes, the motion of the human skeleton, and the deformation of the surfaces. Several examples are presented illustrating positional constraints, dynamics, behavioural animation and finite element theory.