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51	Implicit representation of inscribed volumes Sahbaei, Parto 01 May 2017 (has links) We present an implicit approach for constructing smooth isolated or interconnected 3-D inscribed volumes which can be employed for volumetric modeling of various kinds of spongy or porous structures, such as volcanic rocks, pumice stones, Cancellus bones *, liquid or dry foam, radiolarians, cheese, and other similar materials. The inscribed volumes can be represented in their normal or positive forms to model natural pebbles or pearls, or in their inverted or negative forms to be used in porous structures, but regardless of their types, their smoothness and sizes are controlled by the user without losing the consistency of the shapes. We introduce two techniques for blending and creating interconnections between these inscribed volumes to achieve a great flexibility to adapt our approach to different types of porous structures, whether they are regular or irregular. We begin with a set of convex polytopes such as 3-D Voronoi diagram cells and compute inscribed volumes bounded by the cells. The cells can be irregular in shape, scale, and topology, and this irregularity transfers to the inscribed volumes, producing natural-looking spongy structures. Describing the inscribed volumes with implicit functions gives us a freedom to exploit volumetric surface combinations and deformations operations effortlessly / Graduate Marching Cubes Implicit Modeling Inscribed Volumes Marching Tetra-hedra Extended Marching Cubes Dual Marching Cubes Dual Contouring Spline Inscribed Curves Subsurface Scattering Laguerre tessellation Radiolarians Voronoi Diagram The BlobTree Octree porous surfaces spongy surfaces Polytopes
52	Optimalizované sledování paprsku / Optimized Ray Tracing Brich, Radek Unknown Date (has links) Goal of this work is to write an optimized program for visualization of 3D scenes using ray tracing method. First, the theory of ray tracing together with particular techniques are presented. Next part focuses on different approaches to accelerate the algorithm. These are space partitioning structures, fast ray-triangle intersection technique and possibilities to parallelize the whole ray tracing method. A standalone chapter addresses the design and implementation of the ray tracing program.
53	Algorithmique hiérarchique parallèle haute performance pour les problèmes à N-corps Fortin, Pierre 27 November 2006 (has links) (PDF) Cette thèse porte sur la méthode dite « méthode multipôle rapide » qui résout hiérarchiquement le problème à N-corps avec une complexité linéaire pour n'importe quelle précision. Dans le cadre de l'équation de Laplace, nous souhaitons pouvoir traiter efficacement toutes les distributions de particules rencontrées en astrophysique et en dynamique moléculaire.<br /> Nous étudions tout d'abord deux expressions distinctes du principal opérateur (« multipôle-to-local ») ainsi que les bornes d'erreur associées. Pour ces deux expressions, nous présentons une formulation matricielle dont l'implémentation avec des routines BLAS (Basic Linear Algebra Subprograms) permet d'améliorer fortement l'efficacité de calcul. Dans la gamme de précisions qui nous intéresse, cette approche se révèle plus performante que les améliorations existantes (FFT, rotations et ondes planes), pour des distributions uniformes ou non.<br /> Outre une nouvelle structure de données pour l'octree sous-jacent et des contributions algorithmiques à la version adaptative, nous avons aussi efficacement parallélisé notre méthode en mémoire partagée et en mémoire distribuée. Enfin, des comparaisons avec des codes dédiés justifient l'intérêt de notre code pour des simulations en astrophysique. problème à N-corps méthode multipôle rapide algorithme de Barnes & Hut équation de Laplace équation de Poisson astrophysique dynamique moléculaire borne d'erreur Transformée Rapide de Fourier rotations ondes planes routines BLAS octree parallélisme mémoire partagée mémoire distribuée
54	Dynamic Visualization of Space Weather Simulation Data / Dynamisk visualisering av rymdvädersimuleringsdata Sand, Victor January 2014 (has links) The work described in this thesis is part of the Open Space project, a collaboration between Linköping University, NASA and the American Museum of Natural History. The long-term goal of Open Space is a multi-purpose, open-source scientific visualization software. The thesis covers the research and implementation of a pipeline for preparing and rendering volumetric data. The developed pipeline consists of three stages: A data formatting stage which takes data from various sources and prepares it for the rest of the pipeline, a pre-processing stage which builds a tree structure of of the raw data, and finally an interactive rendering stage which draws a volume using ray-casting. The pipeline is a fully working proof-of-concept for future development of Open Space, and can be used as-is to render space weather data using a combination of suitable data structures and an efficient data transfer pipeline. Many concepts and ideas from this work can be utilized in the larger-scale software project. nasa space space weather scientific visualization visualization 3d graphics volumetric rendering c++ opencl opengl glsl amnh pipeline voxel voxels data structures tsp tree octree gpu gpgpu Media and Communication Technology Medieteknik
55	Vizualizace a uživatelské rozhraní pro řídicí systém divadelního jeviště / Visualization and User Interface for Theatre Stage Control System Kobza, Lukáš January 2013 (has links) This thesis deals with questions of modelling and 3D visualization. Also, it involves an overview of technical equipment on a theatre stage and control systems of this machinery with accent on user interface and all the interaction with staff. Afterwards, the main topic is the investigation of 3D visualization utilization technology in the field of theatre stage control systems and then the proposal and implementation of the theatre stage 3D visualization application follows in order to increase a clearness and safety of operation with the theatre control system.

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