Surface Remeshing and Applications

Due to the focus of popular graphic accelerators, triangle meshes remain the primary representation for 3D surfaces. They are the simplest form of interpolation between surface samples, which may have been acquired with a laser scanner, computed from a 3D scalar field resolved on a regular grid, or identified on slices of medical data. Typical methods for the generation of triangle meshes from raw data attempt to lose as less information as possible, so that the resulting surface models can be used in the widest range of scenarios. When such a general-purpose model has to be used in a particular application context, however, a pre-processing is often worth to be considered. In some cases, it is convenient to slightly modify the geometry and/or the connectivity of the mesh, so that further processing can take place more easily. Other applications may require the mesh to have a pre-defined structure, which is often different from the one of the original general-purpose mesh. The central focus of this thesis is the automatic remeshing of highly detailed surface triangulations. Besides a thorough discussion of state-of-the-art applications such as real-time rendering and simulation, new approaches are proposed which use remeshing for topological analysis, flexible mesh generation and 3D compression. Furthermore, innovative methods are introduced to post-process polygonal models in order to recover information which was lost, or hidden, by a prior remeshing process. Besides the technical contributions, this thesis aims at showing that surface remeshing is much more useful than it may seem at a first sight, as it represents a nearly fundamental step for making several applications feasible in practice

3D Object Comparison Based on Shape Descriptors

No abstract availabl

Object Matching and Morphing Calculation Based On Guarding Framework

计算机图形学的发展历程中，三维模型的模型化和处理技术在许多视觉计算任务中占据着非常重要的位置，一直是中外学者们研究的强大动力。目前，已经有提出了许多根本的问题，并进行了积极的研究。通常，三维表面和实心模型以三角网格和四面体网格分别表示。三维模型的曲线骨骼有效地简化了原始模型，并且抽取了原始模型的重要拓扑和几何特征。这样一个简化的图结构有利于一些图形分析应用，比如三维物体的匹配和变形计算，而这正是计算机图形学的重要研究课题，也是本文的重点所在。 本文研究了骨骼化方法和三维区域看守理论，提出了一种在统一的框架中使用图形的骨骼计算最小看守点集合的方法。之后，基于这个看守点计算过程，提出算法匹配两个...With the development of computer graphics, the modeling and processing of models in the 3D space has been a research thrust and playing important roles in many visual computing tasks. Many fundamental problems have been raised and active research has been conducted these days. 3D surfaces and solid models are usually represented by triangle meshes and tetrahedral meshes respectively. The curve-ske...学位：工学硕士院系专业：信息科学与技术学院自动化系_系统工程学号：2322007115284

Graph matching a skeletonized theoretical morphospace with a cladogram for gomphonemoid-cymbelloid diatoms (Bacillariophyta)

A three-dimensional (3D) theoretical morphospace of gomphonemoid and cymbelloid diatoms was skeletonized using concepts from extended Reeb graph analysis and Morse theory. The resultant skeleton tree was matched to a cladogram of the same group of related taxa using adjacency matrices of the trees and ordinated with multidimensional scaling (MDS) of leaf nodes. From this, an unweighted path matrix based on the number of branches between leaf nodes was ordinated to determine degree of matched tree structures. A constrained MDS of the path matrix, weighted by ranked MDS leaf node groups as facets, was used to interpret taxon environmental tolerances and habitat preferences with respect to adaptive value. The methods developed herein provided a way to combine results from morphological and phylogenetic analyses and interpret those results with respect to an aspect of evolutionary process, namely, adaptation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/83675/1/JLP-JBS2011.pdf-