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Practical Point-in-Polygon Tests Using CSG Representations of Polygons [chapter]

Robert J. Walker, Jack Snoeyink
1999 Lecture Notes in Computer Science  
We investigate the use of a constructive solid geometry (CSG) representation of polygons in testing if points fall within them; this representation consists of a tree whose nodes are either Boolean operators  ...  Existing Point-in-Polygon Algorithms Haines [10] gives a thorough comparative treatment of existing point-in-polygon algorithms.  ...  Conclusion We have presented an algorithm for performing point-in-polygon tests using a constructive solid geometry (CSG) representation of polygons.  ... 
doi:10.1007/3-540-48518-x_7 fatcat:d4ke3ucvo5fhzp4ufpzjl5fz4i

Using CSG representations of polygons for practical point-in-polygon tests

Robert Walker, Jack Snoeyink
1997 ACM SIGGRAPH 97 Visual Proceedings: The art and interdisciplinary programs of SIGGRAPH '97 on - SIGGRAPH '97  
A CSG representation for polygons is used for performing point-in-polygon tests, and is compared to existing methods.  ...  Using CSG Representations of Polygons for Practical Point-in-Polygon Tests Extended Abstract There have been many point-in-polygon test algorithms presented; Haines 1 gives a thorough comparative treatment  ...  of existing point-in-polygon algorithms, and the terminology that we use is based upon that work.  ... 
doi:10.1145/259081.259239 dblp:conf/siggraph/WalkerS97 fatcat:glkmhdapfrgt3mluhsqtl3mxkm

Determination of mass properties of polygonal CSG objects in parallel

Chandrasekhar Narayanaswami, William Randolph Franklin
1991 Proceedings of the first ACM symposium on Solid modeling foundations and CAD/CAM applications - SMA '91  
Determine the local topology representation of the evaluated object. Use the local topology representation to determine the mass properties of the CSG object.  ...  Since speed is important in these interactive applications, a fast and practical parallel algorithm for this problem will be useful.  ... 
doi:10.1145/112515.112550 dblp:conf/sma/NarayanaswamiF91 fatcat:yckepyn3y5f4ndw2j2mfbtky7a

Representation, Boundary Computation and Fast Display of CSG Models with NURBS Primitives [chapter]

Shankar Krishnan, Subodh Kumar, Dinesh Manocha
1997 IFIP Advances in Information and Communication Technology  
Based on algorithms for trapezoidation of polygons, partitioning of polygons using polygonal chains, surface intersection of high degree spline surfaces and ray-shooting, the boundaries of the resulting  ...  The system has been used to convert parts of a submarine storage and handling system model represented as more than 2; 000 CSG trees.  ...  The CSG model of the submarine storage and handling system was provided to us by Greg Angelini, Jim Boudreaux and Ken Fast at Electric Boat; thanks goes to them.  ... 
doi:10.1007/978-0-387-35187-2_29 fatcat:ulddt6sqmrdnpjzdmmfcrqn4c4

POLYGONIZATION OF IMPLICIT SURFACES WITH CONSTRUCTIVE SOLID GEOMETRY

BRIAN WYVILL, KEES VAN OVERVELD
1996 International journal of shape modeling  
These potential fields are parameterized by configurations of so called skeletal elements. The resulting system, unlike most CSG systems, combines blended and unblended primitives.  ...  A polygonisation algorithm is presented which extends an existing skeletal implicit surface technique to include operations based on Constructive Solid Geometry between blended groups of implicit surface  ...  Geoff Wyvill of the University of Otago for their encouragement past and present. This work is partially supported by the Natural Sciences and Engineering Council of Canada.  ... 
doi:10.1142/s0218654396000142 fatcat:kuxlfxxl6rgpdo63cb2uwe6bme

Cultural Heritage Preservation Using Constructive Shape Modeling

C. Vilbrandt, G. Pasko, A. Pasko, P.-A. Fayolle, T. Vilbrandt, J. R. Goodwin, J. M. Goodwin, T. L. Kunii
2004 Computer graphics forum (Print)  
Constructive Solid Geometry (CSG) and Function Representation (FRep) are examined and practically applied as mathematical representations producing compressed yet precise data structures, thus providing  ...  We examine the application of fitting of a parameterized FRep model to a cloud of data points as a step towards automation of the modeling process.  ...  Mainly, these representations are discussed from the practical modeling point of view.  ... 
doi:10.1111/j.1467-8659.2004.00003.x fatcat:rcvz22cldng75a3tlbsdbmdcmu

Out of core Polyhedral Union and its Application to Interactive Shadow Rendering [article]

J. Fedorkiw, C. Smith, S. Ghali
2006 Computer Graphics and Visual Computing  
Four methods for storing a set of points using a computer are currently known: Boundary representations, Constructive Solid Geometry, Binary Space Partitioning trees, and Nef polyhedra.  ...  We show that the algorithm is practical by providing time and space statistics. We also show the benefit of using the resulting union solid for computing interactive shadows.  ...  Compared to CSG and Nef representations, a BSP tree reverses the roles of interior and leaf nodes.  ... 
doi:10.2312/localchapterevents/tpcg/tpcg06/141-148 dblp:conf/tpcg/FedorkiwSG06 fatcat:zw2mroa23rgizcuhsswnznkimi

Solid representation and operation using extended octrees

Pere Brunet
1990 ACM Transactions on Graphics  
Configurations can then be used in the point membership classification algorithms.  ...  Due to the simplicity of the Boolean operation algorithms [19], extended octrees have been used as a secondary representation model in the DMI solid modeling system [22] .  ...  Esterling for his useful ideas and comments, and Josep Fontdecaba and Francesc Bate for their help in the implementation of some of the proposed algorithms.  ... 
doi:10.1145/78956.78959 fatcat:ufjd4khn6jgg7mcm4dc6w3wnza

Asymptotic speed-ups in constructive solid geometry

D. Eppstein
1995 Algorithmica  
We convert constructive solid geometry input to explicit representations of polygons, polyhedra, or more generally d-dimensional polyhedra, in time O(n d ), improving a previous O(n d log n) bound.  ...  We then show that any Boolean formula can be preprocessed in time O(n log n/ log log n) so that the value of the formula can be maintained, as variables are changed one by one, in time O(log n/ log log  ...  Dynamic maintenance of formula values Goodrich's [8] algorithm for testing CSG emptiness (and for constructing an explicit representation of a CSG polygon) traverses the space in which the polygon is  ... 
doi:10.1007/bf01190849 fatcat:4rnajo7dsfcmnamizdhr5renuy

Fast Exact Booleans for Iterated CSG using Octree-Embedded BSPs

Julius Nehring-Wirxel, Philip Trettner, Leif Kobbelt
2021 Computer-Aided Design  
Consequently, BSP Booleans and mesh extraction are formulated in terms of mesh cutting. The octree is used as a global acceleration structure to keep modifications local and bound the BSP complexity.  ...  We demonstrate our system in two iterated CSG settings: sweep volumes and a milling simulation.  ...  To avoid having to increase the resolution when creating new intersection vertices they use a purely plane-based representation for convex polygons which is a subset of the class of Nef polygons [17]  ... 
doi:10.1016/j.cad.2021.103015 fatcat:qimlfhm3zjffritn5u7n5ggpqu

EMBER

Philip Trettner, Julius Nehring-Wirxel, Leif Kobbelt
2022 ACM Transactions on Graphics  
Exactness is guaranteed by using a plane-based representation for the input meshes along with recently introduced homogeneous integer coordinates.  ...  Boolean operators are an essential tool in a wide range of geometry processing and CAD/CAM tasks.  ...  ACKNOWLEDGMENTS We use the Thingi10K data set  ... 
doi:10.1145/3528223.3530181 fatcat:4myw33pd4vavzj5aohyzrzp4a4

3D Metamorphosis Between Different Types of Geometric Models

David E. Breen, Sean Mauch, Ross T. Whitaker, Jia Mao
2001 Computer graphics forum (Print)  
We have developed techniques for converting several types of geometric models (polygonal meshes, CSG models and MRI scans) into distance volumes, the volumetric representation required by our level set  ...  A dilation of size α, Dα, corresponds to the solution of Equation 9 at t © α using the positive sign, and likewise erosion, Eα, uses the negative sign.  ...  The polygonal model was provided by Hughues Hoppe of Microsoft Research, and the MRI scan was provided by the University of Utah's SCI Institute.  ... 
doi:10.1111/1467-8659.00496 fatcat:5wca5e76tbek7ogp2pqcooihzi

Representing geographical objects with scale‐induced indeterminate boundaries: A neural network‐based data model

J. L. Silván‐Cárdenas, L. Wang, F. B. Zhan
2009 International Journal of Geographical Information Science  
The degree of uncertainty of many geographical objects has long been known to be in intimate relation with the scale of its observation and representation.  ...  The construction of complex fuzzy regions, as well as lines and points, is discussed and illustrated with examples.  ...  Acknowledgements The authors would like to thank the anonymous referees for their comments that helped to reach the final shape of this article.  ... 
doi:10.1080/13658810801932021 fatcat:fzejybjvxvgqrloempjkwduom4

3D modeling with silhouettes

Alec Rivers, Frédo Durand, Takeo Igarashi
2010 ACM Transactions on Graphics  
We evaluate our approach by modeling a random sampling of man-made objects taken from the words in WordNet, and show that all of the tested man-made objects can be modeled quickly and easily using our  ...  Arbitrarily complex models can be constructed by assembling them out of parts defined by their silhouettes, which can be combined using CSG operations.  ...  Acknowledgments Thanks to Danielle Magrogan for providing many of the models in the range evaluation, and the reviewers of the MIT pre-deadline.  ... 
doi:10.1145/1778765.1778846 fatcat:heu6tsxhxfhmddytxr6j3r5num

3D modeling with silhouettes

Alec Rivers, Frédo Durand, Takeo Igarashi
2010 ACM SIGGRAPH 2010 papers on - SIGGRAPH '10  
We evaluate our approach by modeling a random sampling of man-made objects taken from the words in WordNet, and show that all of the tested man-made objects can be modeled quickly and easily using our  ...  Arbitrarily complex models can be constructed by assembling them out of parts defined by their silhouettes, which can be combined using CSG operations.  ...  Acknowledgments Thanks to Danielle Magrogan for providing many of the models in the range evaluation, and the reviewers of the MIT pre-deadline.  ... 
doi:10.1145/1833349.1778846 fatcat:hhteqhm7xfg6hoxeyyaqldzy54
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