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348
ComputerGenerated PenandInk Illustration
, 1996
"... This dissertation describes the principles of penandink illustration, and shows how a great number of them can be implemented as part of an automated rendering system. Illustration techniques in general, and penandink rendering in particular, offer great potential for creating effective images f ..."
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Cited by 219 (11 self)
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This dissertation describes the principles of penandink illustration, and shows how a great number of them can be implemented as part of an automated rendering system. Illustration techniques in general, and penandink rendering in particular, offer great potential for creating effective images from CAD models. And with the computer's ability to manipulate increasingly large models, communicating complex information in an effective and comprehensible manner is becoming an important problem. However, this potential remains relatively untapped in the field of computer graphics. After discussing principles of traditional penandink rendering, this dissertation shows how the traditional graphics pipeline must be modified to support penandink rendering. Then, it introduces the new concept of prioritized stroke textures. Prioritized stroke textures form the central mechanism by which strokes are generated so as to both convey a certain texture, such as "bricks", and achieve a target tone simultaneously. Prioritized stroke textures also have the advantages of being resolution dependent
OutofCore Compression for Gigantic Polygon Meshes
, 2003
"... Polygonal models acquired with emerging 3D scanning technology or from large scale CAD applications easily reach sizes of several gigabytes and do not fit in the address space of common 32bit desktop PCs. In this paper we propose an outofcore mesh compression technique that converts such gigantic ..."
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Cited by 81 (23 self)
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Polygonal models acquired with emerging 3D scanning technology or from large scale CAD applications easily reach sizes of several gigabytes and do not fit in the address space of common 32bit desktop PCs. In this paper we propose an outofcore mesh compression technique that converts such gigantic meshes into a streamable, highly compressed representation. During decompression only a small portion of the mesh needs to be kept in memory at any time. As full connectivity information is available along the decompression boundaries, this provides seamless mesh access for incremental incore processing on gigantic meshes. Decompression speeds are CPUlimited and exceed one million vertices and two million triangles per second on a 1.8 GHz Athlon processor.
Polygonization of NonManifold Implicit Surfaces
, 1995
"... A method is presented to broaden implicit surface modeling. The implicit surfaces usually employed in computer graphics are two dimensional manifolds because they are defined by realvalued functions that impose a binary regionalization of space (i.e., an inside and an outside). When tiled, these su ..."
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Cited by 50 (0 self)
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A method is presented to broaden implicit surface modeling. The implicit surfaces usually employed in computer graphics are two dimensional manifolds because they are defined by realvalued functions that impose a binary regionalization of space (i.e., an inside and an outside). When tiled, these surfaces yield edges of degree two. The new method allows the definition of implicit surfaces with boundaries (i.e., edges of degree one) and intersections (i.e., edges of degree three or more). These nonmanifold implicit surfaces are defined by a multiple regionalization of space. The definition includes a list of those pairs of regions whose separating surface is of interest. Also presented is an implementation that converts a nonmanifold implicit surface definition into a collection of polygons. Although following conventional implicit surface polygonization, there are significant differences that are described in detail. Several example surfaces are defined and polygonized. CR Categories and Subject Descriptors: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling  Curve, Surface, Solid, and Object Representations. Additional Keywords and Phrases: Implicit Surface, NonManifold, Polygonization. 1
Using Generic Programming for Designing a Data Structure for Polyhedral Surfaces
 Comput. Geom. Theory Appl
, 1999
"... Appeared in Computational Geometry  Theory and Applications 13, 1999, 6590. Software design solutions are presented for combinatorial data structures, such as polyhedral surfaces and planar maps, tailored for program libraries in computational geometry. Design issues considered are flexibility, ..."
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Cited by 48 (4 self)
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Appeared in Computational Geometry  Theory and Applications 13, 1999, 6590. Software design solutions are presented for combinatorial data structures, such as polyhedral surfaces and planar maps, tailored for program libraries in computational geometry. Design issues considered are flexibility, time and space efficiency, and easeofuse. We focus on topological aspects of polyhedral surfaces and evaluate edgebased representations with respect to our design goals. A design for polyhedral surfaces in a halfedge data structure is developed following the generic programming paradigm known from the Standard Template Library STL for C++. Connections are shown to planar maps and facebased structures. Key words: Library design; Generic programming; Combinatorial data structure; Polyhedral surface; Halfedge data structure 1 Introduction Combinatorial structures, such as planar maps, are fundamental in computational geometry. In order to be useful in practice, a solid library for compu...
Metamorphosis of Arbitrary Triangular Meshes
 ABSTRACT TO APPEAR IN IEEE COMPUTER GRAPHICS AND APPLICATIONS
"... Recently, animations with deforming objects have been frequently used in various computer graphics applications. Metamorphosis (or morphing) of threedimensional objects is one of the techniques which realizes shape transformation between two or more existing objects. In this paper, we present an ef ..."
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Cited by 43 (3 self)
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Recently, animations with deforming objects have been frequently used in various computer graphics applications. Metamorphosis (or morphing) of threedimensional objects is one of the techniques which realizes shape transformation between two or more existing objects. In this paper, we present an efficient framework for metamorphosis between two topologically equivalent, arbitrary meshes with the control of surface correspondences by the user. The basic idea of our method is to partition meshes according to the reference shapes specified by the user, whereby vertextovertex correspondences between the two meshes can be specified. Each of the partitioned meshes is embedded into a polygonal region on the plane with harmonic mapping. Those embedded meshes have the same graph structure as their original meshes. By overlapping those two embedded meshes, we can establish correspondence between them. Based on this correspondence, metamorphosis is achieved by interpolating the corresponding vertices from one mesh 1 to the other. We demonstrate that the minimum control of surface correspondences by the user generates sophisticated results of the interpolation between two meshes.
Automatic Surface Reconstruction From Point Sets in Space
 Computer Graphics Forum
, 2000
"... In this paper an algorithm is proposed that takes as input a generic set of unorganized points, sampled on a real object, and returns a closed interpolating surface. Specifically, this method generates a closed 2manifold surface made of triangular faces, without limitations on the shape or genus of ..."
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Cited by 40 (5 self)
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In this paper an algorithm is proposed that takes as input a generic set of unorganized points, sampled on a real object, and returns a closed interpolating surface. Specifically, this method generates a closed 2manifold surface made of triangular faces, without limitations on the shape or genus of the original solid. The reconstruction method is based on generation of the Delaunay tetrahedralization of the point set, followed by a sculpturing process constrained to particular criteria. The main applications of this tool are in medical analysis and in reverse engineering areas. It is possible, for example, to reconstruct anatomical parts starting from surveys based on TACs or magnetic resonance.
Matchmaker: Manifold BReps for nonmanifold rsets
 Proceedings of the ACM Symposium on Solid Modeling
, 1999
"... Many solid modeling construction techniques produce nonmanifold rsets (solids). With each nonmanifold model N we can associate a family of manifold solid models that are infinitely close to N in the geometric sense. For polyhedral solids, each nonmanifold edge of N with 2k incident faces will be ..."
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Cited by 40 (20 self)
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Many solid modeling construction techniques produce nonmanifold rsets (solids). With each nonmanifold model N we can associate a family of manifold solid models that are infinitely close to N in the geometric sense. For polyhedral solids, each nonmanifold edge of N with 2k incident faces will be replicated k times in any manifold model M of that family. Furthermore, some nonmanifold vertices of N must also be replicated in M, possibly several times. M can be obtained by defining, in N, a single adjacent face TA(E,F) for each pair (E,F) that combines an edge E and an incident face F. The adjacency relation satisfies TA(E,TA(E,F))=F. The choice of the map A defines which vertices of N must be replicated in M and how many times. The resulting manifold representation of a nonmanifold solid may be encoded using simpler and more compact datastructures, especially for triangulated model, and leads to simpler and more efficient algorithms, when it is used instead of a nonmanifold repre...
An Efficient Algorithm for Finding the CSG Representation of a Simple Polygon
, 1989
"... Modeling twodimensional and threedimensional objects is an important theme in computer graphics. Two main types of models are used in both cases: boundary representations, which represent the surface of an object explicitly but represent its interior only implicitly, and constructive solid geometr ..."
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Cited by 37 (9 self)
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Modeling twodimensional and threedimensional objects is an important theme in computer graphics. Two main types of models are used in both cases: boundary representations, which represent the surface of an object explicitly but represent its interior only implicitly, and constructive solid geometry representations, which model a complex object, surface and interior together, as a boolean combination of simpler objects. Because neither representation is good for all applications, conversion between the two is often necessary. We consider the problem of converting boundary representations of polyhedral objects into constructive solid geometry (CSG) representations. The CSG representations for a polyhedron P are based on the halfspaces supporting the faces of P . For certain kinds of polyhedra this problem is equivalent to the corresponding problem for simple polygons in the plane. We give a new proof that the interior of each simple polygon can be represented by a monotone...