[pt] O principal objetivo deste trabalho é apresentar um novo método para visualização de variedades implícitas de dimensão 3 mergulhadas no R4. Esse método consiste primeiramente de um pré-processamento em CPU utilizando uma árvore 16-Tree e a Aritmética Intervalar para encontrar as regiões do domínio onde a variedade se encontra. Esses dados são posteriormente processados em GPU para efetuar a visualização, e para isso foi utilizada uma generalização da técnica Ray Casting. / [en] The main objective of this work is to present a new method for the visualization of implicit 3-manifolds in R4. This method consists primarily of a preprocessing in the CPU using a 16-tree and Interval Arithmetic to detect regions of the domain where the variety is present. These data are then processed in the GPU to perform the visualization, and for this a generalization of Ray Casting technique was adopted.

Made available in DSpace on 2016-12-12T17:38:34Z (GMT). No. of bitstreams: 1 Allan Yoshio Hasegawa.pdf: 18253702 bytes, checksum: e99aeb0d0d09ebc27b20111c88bac58f (MD5) Previous issue date: 2015-09-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work were studied the main geometric representations in the context of machining simulations and its data structures. Several interactive rendering methods for complex model were studied as well. After the exploratory phase, a prototype simulator using Distance Fields and ray cast was developed. Tests were performed, concluding that the Distance Fields representation is suitable for machining simulation as it offers efficient Boolean operations, practical memory requirements and methods for interactive rendering of complex models with ray casting. / Neste trabalho foram estudadas as principais representações geométricas no contexto de simulações de usinagem e as estruturas de dados utilizadas por estas representações. Diversas técnicas de renderização interativa para modelos complexos foram exploradas. Após a fase exploratória, foi desenvolvido um protótipo de simulador usando Campos de Distância e ray casting. Testes foram executados, concluindo que Campos de Distância é uma representação adequada para simulações de usinagem, providenciando operações booleanas eficientes, consumo prático de memória e oferecendo uma visualização interativa de modelos complexos usando ray casting.

The primary concern of this work is real-time fluid simulation on modern programmable graphics hardware. It starts by introducing fundamental fluid simulation principles with focus on Smoothed particle hydrodynamics technique. The following discussion then provides a brief introduction to OpenCL as well as contemporary GPU hardware and outlines their programming specifics in comparison with CPUs. Finally, the last two chapters of this work, detail the problem analysis and its implementation.

Computing surface and/or object intersections is a cornerstone of many algorithms in Geometric Modeling and Computer Graphics, for example Set Operations between solids, or surface Ray Casting display. We present an object centered, information preserving, hierarchical representation for polyhedra called Prism Tree. We use the representation to decompose the intersection algorithms into two steps: the localization of intersections, and their processing. When dealing with polyhedra with many faces (typically more than one thousand), the first step is by far the most expensive. The Prism Tree structure is used to compute efficiently this localization step. A preliminary implementation of the Set Operations and Ray casting algorithms has been constructed.

Turning and milling are the main manufacturing techniques in industry. A great deal of time and money is spent for machining operations. Although most of the time, the tool path of a CNC machine tool is generated by a Computer Aided Manufacturing (CAM) software package, to be sure that the result of the machining operation will be as required, it is necessary to use a simulation software. There are various machining simulation software packages available in the market. However, they are not only expensive, but also specialized for only one of the before mentioned machining techniques. Most of the companies in the industry are small or medium scale ones and, it is not so easy for them to afford a specialized simulation software for that purpose. In this thesis, it is aimed to develop a software package, which will be used to simulate advanced industrial machining processes, including turning and milling. Dexelmodeling, which is generated by ray casting, and sweep plane algorithm withpolygon clipping technique are used forvisualization. For polygon clipping technique, outer surfaces of the resultant workpiece are generated from planar contours. The software is developed in C# programming language and DirectX libraries are utilizedfor visualization purposes. With the aid of this software, it is also aimed to visually confirm the validity of both mill and lathe NC-code, by representing highly accurate 3D displayed results of these simulations.

Mannheim, Univ., Diss., 2006.

[pt] Este trabalho descreve um método para a visualização de terrenos e objetos por meio da combinação de dois algoritmos, um para terrenos e um para objetos. Nosso propósito é gerar, eficaz e rapidamente, imagens aéreas de um terreno com objetos como casas, veículos e linhas de transmissão e assim permitir um vôo simulado. Para os objetos, descritos por linhas e polígonos, é usado o algoritmo de Z-Buffer; para o terreno, descrito através de mapas de alturas, é usado o algoritmo de lançamento de raios aperfeiçoado, chamado de algoritmo de Horizonte Flutuante.

[pt] Este trabalho apresenta um estudo sobre exames virtuais, que são técnicas de visualização do interior do corpo humano para fins de avaliação clínica utilizando técnicas de visualização volumétrica. Os exames virtuais pretendem ser uma alternativa para os exames convencionais de endoscopia digestiva, colonoscopia e broncoscopia. Apresentamos um estudo comparativo entre os exames virtuais e seus análogos convencionais analisando vantagens e desvantagens para cada uma das técnicas em concreto.Além disso propomos um algoritmo para acelerar a visualização volumétrica com ray casting e comparamos os resultados com outras técnicas de otimização.

The subject of this thesis is an implementation of realistic rendering of voxel scenes using a graphics card. This work explains the fundamentals of realistic rendering and voxel representation of visual data. It also presents selected hierarchical structures usable for acceleration and describes the desing of a solution focusing on the representation of voxel data and their rendering. The thesis describes libraries created as part of the project and algorithms. It also evaluates time and memory requirements of the application along with graphical output.

No description available.