Deformable Surface Modeling

Publications

Here you can find DesMo articles and other documentation stuff.

Articles
  • Accessing CUDA features in the OpenGL rendering pipeline: A case study using N-Body simulation (pdf)
    Authors: Mario Santos Camillo and Wu, Shin - Ting
    Category: Sibgrapi 2017 Electronic Proceedings
    Abstract: The advances of the graphics programing unit (GPU) architecture and its rapidly evolving towards general purpose GPU make a series of applications adopt a general purpose (GPGPU) and a graphics computing interoperability approach in which the first is used for heavy calculations and the second for 3D graphics rendering. Because GPGPU exposes several hardware features, such as shared memory and thread synchronization mechanism, it allows a developer to write more efficient code. Nevertheless, we conjecture that such hardware features are also available in the graphics computing interface OpenGL 4.5 or later through the graphics concepts: blending, transform feedback, tessellation and instancing. In this paper we assess our conjecture by implementing an N-body simulation with both approaches. We indeed devise a novel non-graphics application to the tessellation hardware and the instanced rendering circuit. Instead of refining a mesh, we use the abstract patch for gaining direct accesses to shared memory. In the place of drawing multiple objects, we apply the instanced rendering technology for improving sequential data accesses. Comparative timing analysis is provided. We believe that these results provide better understanding of the graphics features that are useful for closing the performance gap between OpenGL and a GPGPU architecture, and open a new perspective on implementing solely with the OpenGL graphics applications that require both intense, but pre-specified, memory accesses and 3D graphics rendering.
  • Simulação Realista de Tecidos (in Portuguese) (pdf)
    Authors: Leandro de Pinho Monteiro and Wu, Shin - Ting
    Category: SBGames 2006 Proceedings
    Abstract: A crescente busca pelo realismo nos jogos tem levado à integração da simulação de tecidos para fazer os movimentos de vestuários, sobre um personagem animado, mais próximos da nossa percepção usual. Este artigo objetiva apresentar a eficácia de um paradigma geometricamente exato, fundamentado na teoria de superfície de Cosserat Elástica, para simulação de tecidos, descrevendo uma implementação com integração temporal explícita, de baixo custo computacional. Dessa forma, nossa implementação do modelo deformável resulta em comportamentos físicos convincentes, mesmo usando integrações temporais simples, como as integrações Euler ou Verlet.
  • A Deformable Surface Model on the basis of the Theory of a Cosserat Surface (pdf)
    Author: Wu, Shin - Ting and Vanio Fragoso de Melo
    Category: Sibgrapi 2004 conference proceedings
    Abstract: This paper aims at proposing an elastically deformable surface with use of differential geometric structures. On the basis of the Theory of a Cosserat Surface, a computationally processable equation that relates the accumulated elastic energy and the variations in the differential geometry variables (metric and curvature tensors) of the deformable surface is presented. On the basis of our analysis, we propose a novel algorithm to compute more precisely, without compromising the interface's simplicity, the potential deformation energy in terms of the derivatives of the surface. With our proposal, we may maintain the finite difference scheme for computing deformations iteratively. Some simulation results are included.
  • An approximation for Normal Vectors of Deformable Models (compressed PostScript or pdf)
    Author: Wu, Shin - Ting and Vanio Fragoso de Melo
    Category: Sibgrapi 2003 conference proceedings
    Abstract: This paper explores the use of elements of Differential Geometry to control the manipulation of the deformable model proposed by Terzopoulos et al. for animating deformable objects. Particularly, we are interested on the animation of deformable panels without stretching (area invariant), such as clothes and papers. Based on our analysis we could generate with a little effort several simulations compatible with our expectation.
  • On Improving the Search for Critical Points of Implicit Functions ( pdf)
    Authors: Marcelo de Gomensoro Malheiros, Wu, Shin - Ting
    Category: IS99: The Fourth International Workshop in Implicit Surfaceconference proceedings
    Abstract: Recently, there is a trend to develop efficient polygonization techniques for implicit surfaces, aiming at interactive modeling and animation. One of the most challenging issues for such techniques is to ensure the matching between the topology of the surface and the topology of its polygonal approximation. Therefore, it is important to accurately extract the topological information from a given implicit function. This can be done using Morse theory, which says that the critical points of a real function are intimately related to the topology of its level sets. Previous efforts to locate critical points consist of either employing interval search over the domain of the implicit function or trying to find them incrementally in the neighborhood of selected vertices. In this paper we propose an alternative procedure for a specific skeleton-based model. We use the spatial coherence of the skeleton elements to give a good first guess for the locations of the critical points. Newton's method is then applied to improve the accuracy of these predictions.
  • Hierarchical Skeleton-based Implicit Modeling ( compressed PostScript)
    Author: Marcelo G. Malheiros and Wu, Shin - Ting
    Category: SIBGRAPI'97 conference proceedings published by IEEE
    Abstract: Implicit modeling is a recent trend in Computer Graphics and a variety of skeleton-based models was proposed. This paper presents a hierarchical skeleton-based model that can encompass a wide range of these variants and provides more flexible way for defining implicitly an object shape. We also derived a new decay function, which is computationally cheaper. Some results based on the proposed are also shown.
  • Analyzing a Deformable Model Using Differential Geometry ( compressed PostScript)
    Authors: Paulo Fernandes de Santa Clara Ramos Jr., Wu, Shin - Ting, and Sueli I. R. Costa
    Category: SIBGRAPI'97 conference proceedings published by IEEE
    Abstract:
  • Deformação de Superfícies Não-Rígidas baseada em Princípios Físicos ( in Portuguese)
    Authors: Agnus Azevedo Horta and Wu, Shin - Ting
    Category: Anais SIBGRAPI'95
    Abstract: The physically based deformation model proposed in can simulate almost realistic behaviour for non-rigid objects. But there are some situations that require special handling to obtain really satisfactory results. In this paper we present solutions for three situations: movement restrictions, descontinuities and collisions. We also show some deformation simulations for these situations.
Theses
  • Soluções Numéricas em um Modelo de Tecidos Baseado na Superfície de Cosserat ( compressed PostScript | pdf in Portuguese)
    Author: Leandro de Pinho Monteiro
  • Modelagem e Controle de Caimento e Dobras em Superfícies Deformáveis ( compressed PostScript | pdf in Portuguese)
    Author: Vanio Fragoso de Melo
  • Análise Topológica de um Modelo Implícito ( compressed PostScript in Portuguese)
    Author: Marcelo de Gomensoro Malheiros
  • Um Modelo de Deformações para Superfícies: Análise e Simulações ( compressed PostScript in Portuguese)
    Author: Paulo Fernandes de Santa Clara Ramos Jr.
Technical Reports
  • Deformação de Malhas de Arbitrária Topologia (pdf in Portuguese)
    Author: Matias Rodrigues Costa
    Category: Mestrado's Qualifying Examination Monograph
  • Estimação de Propriedades Geométricas em Malhas de Topologia Arbitrária (pdf in Portuguese)
    Author: Matias Rodrigues Costa
    Category: technical report DCA-01/11 - DCA, FEEC, Unicamp - 2011
    Abstract:
  • DeSMo - Deformable Surface Modeling (pdf)
    Author: Wu Shin-Ting
    Category: technical report DCA-02/11 - DCA, FEEC, Unicamp - 2011
  • Deformação de Superfícies (pdf in Portuguese)
    Authors: Vanio Fragoso de Melo and Wu, Shin - Ting
    Category: technical report DCA-03/06 - DCA, FEEC, Unicamp - 2003
    Abstract: Este relatório técnico tem como objetivo apresentar a teoria de superfícies de Cosserat para descrever a dinâmica de deformação de uma superfície em termos das suas propriedades geométricas locais. Mostraremos uma possível aplicação deste modelo na simulação realística dos movimentos de tecido.
  • Estado de Arte de Modelos Deformáveis (pdf in Portuguese)
    Authors: Vanio Fragoso de Melo and Wu, Shin - Ting
    Category: technical report DCA-02/05 - DCA, FEEC, Unicamp - 2002
    Abstract: Este relatório técnico tem como objetivo apresentar uma revisão bibliográfica e dar um panorama do estado da arte de modelos deformáveis. Ele é parte de um projeto de pesquisa maior, que estamos desenvolvendo no programa de doutorado da Faculdade de Engenharia Elétrica e de Computação (FEEC), no Departamento de Computação e Automação Industrial (DCA), na Universidade Estadual de Campinas (UNICAMP), sob a orientação da Profa. Dr-Ing Wu Shin-Ting. Nosso projeto de pesquisa tem como objetivo final a proposta de um modelo de superfície deformável fisicamente embasado. Os trabalhos aqui apresentados não estão confinados a aqueles que propõem um modelo para superfícies e com aplicação na modelagem e animação de tecidos de pano, mas, há predomínio dos mesmos. Este relatório está longe de esgotar todos os trabalhos propostos, por falta de tempo e espaço ou por não tê-los descobertos ou por não ter tido nenhum tipo de acesso aos mesmos. Para a modelagem de tecidos de pano está próximo de um estudo do ``estado da arte'', porém, para outros objetos é só a apresentação de alguns modelos sem essa preocupação.
  • Deformação de Superfícies Não-Rígidas: Implementação e Análise ( compressed PostScript in Portuguese)
    Authors: Wu, Shin - Ting, Paulo F. S.C.Ramos Jr., and Agnus A. Horta
    Category: technical report DCA-010/97 - DCA, FEEC, Unicamp - 1997
    Abstract: The deformable model proposed by Terzopoulos et al. is founded on the motion equation in Lagrangean form and adjust the elastic deformation by parameters related to the metric and curvature tensors of surfaces. Since it unifies the description of shape and motion, this model significantly simplifies the approach of animation of complex objects.
    The flexibility and the modeling power of this model is recognized by the modeling community. Several subsequent works are made to improve this approach. Two problems, which were not enough discussed, is how to manipulate the parameters to get realistic dynamics behavior and its application domains.
    This work addresses these problems. Using concepts from Differential Geometry, we could identify the relevant simplifications on the physically-based models to derive the deformable model proposed by Terzopoulos et al. Then, we took advantages of the geometric potential of this model and deal more intuitively with parameters in order to get realistic simulation or physical movements through an intuitive interface.
    A major challenge that we faced was the non-independency between these parameters. This interdependency, which is a consequence of the differential relation between the metric and the curvature tensors, is not considered up to now, and, as we could see, it can yield non-realistic deformations.
    In our analysis we deal more specifically with the class of surfaces with a big resistance against stretching and little resistance against curvature. These features would allow us to simulate the behavior of a great variety of physical objects, like a piece of cloth or a sheet of paper.
Posters