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Now showing 1 - 4 of 4
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    Dart Throwing on Surfaces
    (The Eurographics Association and Blackwell Publishing Ltd, 2009) Cline, D.; Jeschke, S.; White, K.; Razdan, A.; Wonka, P.
    In this paper we present dart throwing algorithms to generate maximal Poisson disk point sets directly on 3D surfaces. We optimize dart throwing by efficiently excluding areas of the domain that are already covered by existing darts. In the case of triangle meshes, our algorithm shows dramatic speed improvement over comparable sampling methods. The simplicity of our basic algorithm naturally extends to the sampling of other surface types, including spheres, NURBS, subdivision surfaces, and implicits. We further extend the method to handle variable density points, and the placement of arbitrary ellipsoids without overlap. Finally, we demonstrate how to adapt our algorithm to work with geodesic instead of Euclidean distance. Applications for our method include fur modeling, the placement of mosaic tiles and polygon remeshing.
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    A Shape Grammar for Developing Glyph-based Visualizations
    (The Eurographics Association and Blackwell Publishing Ltd, 2009) Karnick, P.; Jeschke, S.; Cline, D.; Razdan, A.; Wentz, E.; Wonka, P.
    In this paper we address the question of how to quickly model glyph-based Geographic Information System visualizations. Our solution is based on using shape grammars to set up the different aspects of a visualization, including the geometric content of the visualization, methods for resolving layout conflicts and interaction methods. Our approach significantly increases modelling efficiency over similarly flexible systems currently in use.
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    A Comparison of Tabular PDF Inversion Methods
    (The Eurographics Association and Blackwell Publishing Ltd, 2009) Cline, D.; Razdan, A.; Wonka, P.
    The most common form of tabular inversion used in computer graphics is to compute the cumulative distribution table of a probability distribution (PDF) and then search within it to transform points, using an O(logA n) binary search. Besides the standard inversion method, however, several other discrete inversion algorithms exist that can perform the same transformation inO(1) time per point. In this paper, we examine the performance of three of these alternate methods, two of which are new.
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    GPU Rendering of Relief Mapped Conical Frusta
    (The Eurographics Association and Blackwell Publishing Ltd, 2009) Bhagvat, D.; Jeschke, S.; Cline, D.; Wonka, P.
    This paper proposes to use relief-mapped conical frusta (cones cut by planes) to skin skeletal objects. Based on this representation, current programmable graphics hardware can perform the rendering with only minimal communication between the CPU and GPU. A consistent definition of conical frusta including texture parametrization and a continuous surface normal is provided. Rendering is performed by analytical ray casting of the relief-mapped frusta directly on the GPU. We demonstrate both static and animated objects rendered using our technique and compare to polygonal renderings of similar quality.