Simulation de champs sonores de haute qualité pour des applications graphiques interactives. (Simulation of high quality sound fields for interactive graphics applications)

This work is aimed at simulating high quality sound fields for interactive 3D graphics applica-tions. We focused our efforts on three main problems: interactive calculation of sound occlusion byobstacles, integration of sound simulation in an interactive 3D animation system and adaptive simula-tion of sound reflections in reverberant environments. We first present an original method that allowsfor approximating the effects of obstacles on sound waves propagation. This qualitative method isbased on the occlusion of the first Fresnel ellipsoids. We make advantage of the use of 3D graphicshardware to achieve interactive computation rates of the attenuation between a point source and apoint receiver in general environments. A more quantitative method based on the Fresnel-Kirchhofftheory of diffraction is also described. Then, we describe an interactive system for integrated soundand graphics rendering in the context of computer animation or virtual reality. This system integratesthe previous interactive occlusion rendering technique. We will show how other effects such as soundspecular reflections and Doppler shifting are also taken into account. Eventually, we introduce a newadaptive simulation technique based on a hierarchical radiosity-like approach as used in lighting si-mulations. It allows for taking into account global specular and diffuse reflections in the context oftime-varying energy exchanges. The obtained solution is independent of the listening position whichmakes the approach well suited to walkthrough applications. Moreover, the complexity of the processcan be tuned to reach more quantitative results, making it usable for room acoustic quality prediction.These three contributions may allow to design a complete simulation system for rendering a virtualsound scene which could be used in a wide range of applications. These applications, however, do notlimit to acoustic simulations but can also be extended to study radiowave propagation in the contextof mobile communications or wireless networks.