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Now showing 1 - 10 of 6237
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    Fast Continuous Collision Detection among Deformable Models using Graphics Processors
    (The Eurographics Association, 2006) Govindaraju, Naga K.; Kabul, Ilknur; Lin, Ming C.; Manocha, Dinesh; Ming Lin and Roger Hubbold
    We present an interactive algorithm to perform continuous collision detection between general deformable models using graphics processors (GPUs). We model the motion of each object in the environment as a continuous path and check for collisions along the paths. Our algorithm precomputes the chromatic decomposition for each object and uses visibility queries on GPUs to quickly compute potentially colliding sets of primitives. We introduce a primitive classification technique to perform efficient continuous self-collision. We have implemented our algorithm on a 3:0 GHz Pentium IV PC with a NVIDIA 7800 GPU, and we highlight its performance on complex simulations composed of several thousands of triangles. In practice, our algorithm is able to detect all contacts, including self-collisions, at image-space precision in tens of milli-seconds.
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    Progressive Hulls for Intersection Applications
    (Blackwell Publishers, Inc and the Eurographics Association, 2003) Platis, Nikos; Theoharis, Theoharis
    Progressive meshes are an established tool for triangle mesh simplification. By suitably adapting the simplification process, progressive hulls can be generated which enclose the original mesh in gradually simpler, nested meshes. We couple progressive hulls with a selective refinement framework and use them in applications involving intersection queries on the mesh. We demonstrate that selectively refinable progressive hulls considerably speed up intersection queries by efficiently locating intersection points on the mesh. Concerning the progressive hull construction, we propose a new formula for assigning edge collapse priorities that significantly accelerates the simplification process, and enhance the existing algorithm with several conditions aimed at producing higher quality hulls. Using progressive hulls has the added advantage that they can be used instead of the enclosed object when a lower resolution of display can be tolerated, thus speeding up the rendering process.ACM CSS: I.3.3 Computer Graphics-Picture/Image Generation, I.3.5 Computer Graphics-Computational Geometry and Object Modeling, I.3.7 Computer Graphics-Three-Dimensional Graphics and Realism
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    Simulation of Facial Muscle Actions Based on Rational Free Form Deformations
    (Blackwell Science Ltd and the Eurographics Association, 1992) Kalra, Prem; Mangili, Angelo; Thalmann, Nadia Magnenat; Thalmann, Daniel
    This paper describes interactive facilities for simulating abstract muscle actions using Rational Free Form Deformations (RFFD). The particular muscle action is simulated as the displacement of the control points of the control-unit for an RFFD defined on a region of interest. One or several simulated muscle actions constitute a Minimum Perceptible Action (MPA), which is defined as the atomic action unit, similar to Action Unit (AU) of the Facial Action Coding System (FACS), to build an expression.
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    Interactive Rendering of Volumetric Data Sets
    (The Eurographics Association, 1994) Juskiw, "Scott; Durdle, Nelson G.; W. Strasser
    The bela architecture for interactive rendering of regularly structured volumetric data sets is presented. The proposed architecture is scalable and uses custom processors to achieve high-speed shading, projection. and composition of voxel primitives. A general purpose image composition network supports the accumulation of both volumetric and geometric elements into the final rendered scene. Data access contentions between processors are eliminated via the use of an enhanced dual object space and image space partitioning scheme that does not require replication or redistribution of rendered data. The bela architecture is intended for rendering large data sets and meets the performance requirements of a full frame interactive image generation system.
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    Constellation Models for Sketch Recognition
    (The Eurographics Association, 2006) Sharon, Dana; Panne, Michiel van de; Thomas Stahovich and Mario Costa Sousa
    Sketch-based modeling shares many of the difficulties of the branch of computer vision that deals with single image interpretation. Most obviously, they must both identify the parts observed in a given 2D drawing or image.We draw on constellation models first proposed in the computer vision literature to develop probabilistic models for object sketches, based on multiple example drawings. These models are then applied to estimate the most-likely labels for a new sketch. A multi-pass branch-and-bound algorithm allows well-formed sketches to be quickly labelled, while still supporting the recognition of more ambiguous sketches. Results are presented for five classes of objects.
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    The Impulse Graph: A New Dynamic Structure For Global Collisions
    (Blackwell Publishers Ltd and the Eurographics Association, 2000) Baciu, George; Keung Wong, Sai
    In interactive virtual environments and dynamic simulations, collisions between complex objects and articulated bodies may occur simultaneously at multiple points or regions of interference. Many solutions to the collision response problem are formulated based on the local pair-wise contact dynamics. In this article, we present a new solution to the global interactions and dynamic response between multiple structures in a three-dimensional environment. This is based on a new dynamic impulse graph that tracks the reaction forces through the entire system and gives a global view of all the interactions in a multibody system.
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    Dynamic Load Balancing within a High PerformanceGraphics System
    (The Eurographics Association, 1991) Selzer, Harald; A. Kaufman
    Interactive 3D graphics applications require significant arithmetic processing to meet the ever-inreasing desire for higher image complexity and higher resolution in displayed images. This paper describes a graphics processor architecture with a high degree of parallelismconnected to a distributed frame buffer. The architecture can be configured with an arbitrary number of identical, high level programmable processors operating in parallel.Within the architecture an automatic load balancing mechanism is presented whichdistributes the processing load between geometry and rendering section. After the unique features of the architecture are described the load balancing mechanismis analyzed and the increase of performance is demonstrated."
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    Comparative Visualization of Instabilities in Crash-Worthiness Simulations
    (The Eurographics Association, 2001) Sommer, Ove; Ertl, Thomas; David S. Ebert and Jean M. Favre and Ronald Peikert
    Since crash-worthiness simulations get more and more important as part of the car development process in order to reduce the cost of development, enhance the product quality, and minimize the time-to-market, the reliability of the simulation results plays a decisive role concerning their significance. Recently the simulation departments of several automotive companies started investigating the quantity and reason for deviations during a number of simulation runs on the same input model. In this case study we discuss different measurements for instability and present a texture-based visualization method which allows the engineers to efficiently explore the simulation results by interactively hiding finite element structures with nearly constant crash performance. Furthermore, we describe those parts of our prototype which use a CORBA layer for providing the same view on a set of simulation results and allowing the visual comparison by using the marker functionality.
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    Sense-Enabled Mixed Reality Museum Exhibitions
    (The Eurographics Association, 2007) Liarokapis, Fotis; Newman, Robert M.; Mount, Sarah; Goldsmith, Dan; Macan, Luis; Malone, Garry; Shuttleworth, James; D. Arnold and F. Niccolucci and A. Chalmers
    During the past few years museums and other cultural heritage institutions have started making use of handheld technologies to provide tourist guides to their visitors. For open-air sites, a number of experimental and commercial applications have been developed based on location-based guides. However, in museum environments static audiovisual guides are the dominant technologies used. In this paper, we present a novel pervasive mixed reality framework to a sensor network capturing ambient noise that can be used to create tangible cultural heritage exhibitions. Localisation of the visitors can be established in a hybrid manner based on machine vision and a wireless sensor network allowing visitors to interact naturally or with the help of sensors. In terms of interface design, a multimodal mixed reality visualisation domain allows for an audio-visual presentation of cultural heritage artefacts.