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Now showing 1 - 7 of 7
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    Real-time Inextensible Hair with Volume and Shape
    (The Eurographics Association, 2015) Sánchez-Banderas, Rosa María; Barreiro, Héctor; García-Fernández, Ignacio; Pérez, Mariano; Mateu Sbert and Jorge Lopez-Moreno
    Hair simulation is a common topic extensively studied in computer graphics. One of the many challenges in this field is simulating realistic hair in a real-time environment. In this paper, we propose a unified simulation scheme to consider three of the key features in hair simulation; inextensibility, shape preservation and hair-hair interaction. We use an extension to the Dynamic Follow the Leader (DFTL) method to include shape preservation. Our implementation is also coupled with a Lagrangian approach to address the hair-hair interaction dynamics. A GPU-friendly scheme is proposed that is able to exploit the massive parallelism these devices offer, being able to simulate thousands of strands in real-time. The method has been integrated in a game development platform with a shading model for rendering and several test applications have been developed using this implementation.
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    Computing Curvature Information on 3D Meshes from Cultural Heritage Artifacts
    (The Eurographics Association, 2012) López, L.; Torres, J. C.; Soler, F.; Isabel Navazo and Gustavo Patow
    The curvature provides essential information about the features of a object surface. This poster presents an operation that makes it possible to generate the curvature information in the CHiSEL system.
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    Lineal Hull: Two Algorithms for Convex Hull
    (The Eurographics Association, 2012) Sánchez, M. García; Salas, A. León; Cantero, J. C. Torres; Isabel Navazo and Gustavo Patow
    This poster proposes a concept that improves the existing algorithms for convex hull. This concept can be applied whether the initial points are sorted or not. The results show a comparation with Quick-Hull (QH) [BDH96]
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    A Procedural Modeling System for the Creation of Huge Models
    (The Eurographics Association, 2012) Cubero, Francisco; Mas, Albert; Patow, Gustavo; Isabel Navazo and Gustavo Patow
    This paper presents a new general purpose procedural geometrical modeling system. It is focused on providing flexibility, modularity and scalability. Furthermore, it is taylored to manage huge geometric models, with millions of polygons. An out-of-core memory management system assures that any scene size can be generated during the modeling evolution. This generation is performed by a set of rules and operations on geometrical objects, organized as a directed acyclic graph.
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    More Stable SPH-based Fluid Simulation
    (The Eurographics Association, 2012) Perea, Juan J.; Cordero, Juan M.; Isabel Navazo and Gustavo Patow
    The simulation of fluid is a field largely discussed, from the viewpoint of engineering, in the so-called computational fluid dynamics (CFD). A problem that occurs repeatedly in the literature of CFD is the stability of the simulation. One of the elements that introduce instability in any CFD model is the temporal integration method. Among the most commonly used CFD techniques, both in the field of engineering and in the computer graphics, is SPH, which is particularly relevant to its computational simplicity. However, this technique adds stability problems due to the treatment of viscous and pressure terms arising from the formulation of Navier'Stokes. SPH also introduces greater instability by the need to use interpolation functions appropriate to the phenomena that occur in fluid dynamics. We present solutions to these four problems of inestability mentioned: treatment of the terms of pressure and viscosity that appear in the Navier'Stokes, the formulation of the characteristic interpolation function of SPH and treatment of temporal integration.
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    Efficient and Robust Position-Based Fluids for VFX
    (The Eurographics Association, 2015) Alduán, Iván; Tena, Angel; Otaduy, Miguel A.; Mateu Sbert and Jorge Lopez-Moreno
    Designing a fluid simulator with VFX production pipelines in mind is a difficult task where goals like efficiency, robustness and scalability compromise each other. Many impressive fluid simulation methods have been presented in research papers before, but often they do not meet the production and flexibility demands of artists working on actual VFX production pipelines. In this paper we present a particle-based fluid simulation framework, based on the well known Position-Based Fluids (PBF) method, designed to address VFX production demands. Our framework puts special care on data structure design and implementation details. It highlights cache-efficient GPU-friendly data structures, an improved Z-index sort spatial voxelization technique, tuned-up simulation algorithms, and collision treatment based on VDB fields. Altogether, they empower the artist with a very efficient fluid solver, but also with the robustness and versatility needed for simulating very diverse scenes and effects.
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    Bringing Direct Local Control to Interactive Visual Editing of Procedural Buildings
    (The Eurographics Association, 2012) Riu, Adria; Patow, Gustavo; Isabel Navazo and Gustavo Patow
    This paper presents a new system to add direct and persistent local control to the visual editing of rules for procedural buildings, avoiding a combinatorial explosion of grammar rules. In this paper we follow the ideas initially proposed by Lipp and co-workers [LWW08]. For this, we have added a few simple new commands, which are added to the artist-provided ruleset in a way completely transparent to the user. The end-user selects the primitives/assets to modify, and the system automatically incorporates these modifications into the ruleset. This change is performed using graph-rewriting techniques, which are both simple to define and control, but also very powerful and practical for these situations.