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Visibility graph

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147:: the boundary of the polygon forms a Hamiltonian cycle in the visibility graph. It is known that not all visibility graphs induce a simple polygon. However, an efficient algorithmic characterization of the visibility graphs of simple polygons remains unknown. These graphs do not fall into many known families of well-structured graphs: they might not be 186:
of a system of polygons or curves are lines that touch two of them without penetrating them at their points of contact. The bitangents of a set of polygons form a subset of the visibility graph that has the polygon's vertices as its nodes and the polygons themselves as the obstacles. The visibility
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between them. That is, if the line segment connecting two locations does not pass through any obstacle, an edge is drawn between them in the graph. When the set of locations lies in a line, this can be understood as an ordered series. Visibility graphs have therefore been extended to the realm of
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graph approach to the Euclidean shortest path problem may be sped up by forming a graph from the bitangents instead of using all visibility edges, since a Euclidean shortest path may only enter or leave the boundary of an obstacle along a bitangent.
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VisiLibity: A free open source C++ library of floating-point visibility algorithms and supporting data types. This software can be used for calculating visibility graphs of polygonal environments with polygonal holes. A Matlab interface is also
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to the graph. For planning the motion of a robot that has non-negligible size compared to the obstacles, a similar approach may be used after expanding the obstacles to compensate for the size of the robot.
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of the obstacles. Therefore, the Euclidean shortest path problem may be decomposed into two simpler subproblems: constructing the visibility graph, and applying a shortest path algorithm such as
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is the problem of finding a small set of points such that all other non-obstacle points are visible from this set. Certain forms of the art gallery problem may be interpreted as finding a
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The visibility graph of a set of locations that lie in a line can be interpreted as a graph-theoretical representation of a time series. This particular case builds a bridge between
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of the obstacles, where it may turn, so the Euclidean shortest path is the shortest path in a visibility graph that has as its nodes the start and destination points and the
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has the polygon's vertices as its point locations, and the exterior of the polygon as the only obstacle. Visibility graphs of simple polygons must be
496: 201: 97:, and also cite a 1973 description of this method by Russian mathematicians M. B. Ignat'yev, F. M. Kulakov, and A. M. Pokrovskiy. 410: 569: 506:
Lozano-Pérez, Tomás; Wesley, Michael A. (1979), "An algorithm for planning collision-free paths among polyhedral obstacles",
32: 408:; Snoeyink, Jack; Vosoughpour, Hamideh (2017). "Visibility graphs, dismantlability, and the cops and robbers game". 564: 196: 113: 90: 72:
obstacles in the plane: the shortest path between two obstacles follows straight line segments except at the
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Lacasa, Lucas; Luque, Bartolo; Ballesteros, Fernando; Luque, Jordi; Nuño, Juan Carlos (2008).
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attribute the visibility graph method for Euclidean shortest paths to research in 1969 by
36: 24: 322: 228:"Voronoi-Visibility Roadmap-based Path Planning Algorithm for Unmanned Surface Vehicles" 341: 296: 176: 159:. An exception to this phenomenon is that the visibility graphs of simple polygons are 140: 109: 553: 472: 160: 156: 148: 529: 262: 206: 152: 128: 105: 44: 433: 120: 53: 405: 246: 35:
of intervisible locations, typically for a set of points and obstacles in the
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Visibility graphs may also be used to calculate the placement of
475:; Schwarzkopf, Otfried (2000), "Chapter 15: Visibility Graphs", 226:
Niu, Hanlin; Savvaris, Al; Tsourdos, Antonios; Ji, Ze (2019).
543: 297:"From time series to complex networks: The visibility graph" 43:in the graph represents a point location, and each 476: 282: 86: 301:Proceedings of the National Academy of Sciences 8: 519: 423: 381: 340: 330: 312: 274: 272: 218: 64:Visibility graphs may be used to find 370:Discrete & Computational Geometry 7: 202:Fuzzy architectural spatial analysis 471:de Berg, Mark; van Kreveld, Marc; 14: 283:Lozano-PĂ©rez & Wesley (1979) 87:Lozano-PĂ©rez & Wesley (1979) 1: 434:10.1016/j.comgeo.2017.07.001 364:Ghosh, S. K. (1997-03-01). 104:, or as a tool used within 586: 139:The visibility graph of a 508:Communications of the ACM 247:10.1017/S0373463318001005 197:Visibility graph analysis 114:visibility graph analysis 281:, sections 5.1 and 5.3; 66:Euclidean shortest paths 332:10.1073/pnas.0709247105 179:in a visibility graph. 93:on motion planning for 570:Computational geometry 479:Computational Geometry 411:Computational Geometry 18:computational geometry 521:10.1145/359156.359164 455:de Berg et al. (2000) 279:de Berg et al. (2000) 235:Journal of Navigation 82:Dijkstra's algorithm 323:2008PNAS..105.4972L 173:art gallery problem 383:10.1007/BF02770871 145:Hamiltonian graphs 49:visible connection 498:978-3-540-65620-3 307:(13): 4972–4975. 125:dynamical systems 577: 565:Geometric graphs 532: 523: 501: 483:(2nd ed.), 482: 458: 452: 446: 445: 427: 402: 396: 395: 385: 361: 355: 354: 344: 334: 316: 292: 286: 276: 267: 266: 232: 223: 167:Related problems 135:Characterization 95:Shakey the robot 29:visibility graph 585: 584: 580: 579: 578: 576: 575: 574: 550: 549: 540: 514:(10): 560–570, 505: 499: 485:Springer-Verlag 470: 467: 462: 461: 453: 449: 404: 403: 399: 363: 362: 358: 294: 293: 289: 277: 270: 230: 225: 224: 220: 215: 193: 169: 137: 68:among a set of 62: 37:Euclidean plane 25:motion planning 12: 11: 5: 583: 581: 573: 572: 567: 562: 552: 551: 548: 547: 539: 538:External links 536: 535: 534: 503: 497: 473:Overmars, Mark 466: 463: 460: 459: 447: 397: 376:(2): 143–162. 356: 287: 268: 241:(4): 850–874. 217: 216: 214: 211: 210: 209: 204: 199: 192: 189: 177:dominating set 168: 165: 161:cop-win graphs 157:chordal graphs 149:perfect graphs 141:simple polygon 136: 133: 110:urban planning 102:radio antennas 61: 58: 13: 10: 9: 6: 4: 3: 2: 582: 571: 568: 566: 563: 561: 560:Robot control 558: 557: 555: 546: 542: 541: 537: 531: 527: 522: 517: 513: 509: 504: 500: 494: 490: 486: 481: 480: 474: 469: 468: 464: 456: 451: 448: 443: 439: 435: 431: 426: 421: 417: 413: 412: 407: 401: 398: 393: 389: 384: 379: 375: 371: 367: 360: 357: 352: 348: 343: 338: 333: 328: 324: 320: 315: 310: 306: 302: 298: 291: 288: 284: 280: 275: 273: 269: 264: 260: 256: 252: 248: 244: 240: 236: 229: 222: 219: 212: 208: 205: 203: 200: 198: 195: 194: 190: 188: 185: 180: 178: 174: 166: 164: 162: 158: 154: 153:circle graphs 150: 146: 142: 134: 132: 130: 126: 122: 117: 115: 111: 107: 103: 98: 96: 92: 88: 83: 79: 75: 71: 67: 59: 57: 55: 50: 47:represents a 46: 42: 38: 34: 30: 26: 23: 19: 511: 507: 478: 450: 415: 409: 400: 373: 369: 359: 304: 300: 290: 238: 234: 221: 207:Space syntax 181: 170: 138: 129:graph theory 118: 106:architecture 99: 91:Nils Nilsson 63: 60:Applications 28: 15: 487:, pp.  406:Lubiw, Anna 121:time series 54:time series 554:Categories 465:References 425:1601.01298 184:bitangents 56:analysis. 545:included. 457:, p. 316. 418:: 14–27. 392:0179-5376 314:0810.0920 255:0373-4633 70:polygonal 530:17397594 351:18362361 263:67908628 191:See also 112:through 78:vertices 74:vertices 39:. Each 489:307–317 442:3693353 342:2278201 319:Bibcode 528:  495:  440:  390:  349:  339:  261:  253:  526:S2CID 420:arXiv 309:arXiv 259:S2CID 231:(PDF) 213:Notes 155:, or 33:graph 31:is a 22:robot 493:ISBN 388:ISSN 347:PMID 251:ISSN 182:The 171:The 127:and 108:and 45:edge 41:node 27:, a 20:and 516:doi 430:doi 378:doi 337:PMC 327:doi 305:105 243:doi 16:In 556:: 524:, 512:22 510:, 491:, 438:MR 436:. 428:. 416:66 414:. 386:. 374:17 372:. 368:. 345:. 335:. 325:. 317:. 303:. 299:. 271:^ 257:. 249:. 239:72 237:. 233:. 163:. 151:, 131:. 123:, 116:. 533:. 518:: 502:. 444:. 432:: 422:: 394:. 380:: 353:. 329:: 321:: 311:: 285:. 265:. 245::

Index

computational geometry
robot
motion planning
graph
Euclidean plane
node
edge
visible connection
time series
Euclidean shortest paths
polygonal
vertices
vertices
Dijkstra's algorithm
Lozano-PĂ©rez & Wesley (1979)
Nils Nilsson
Shakey the robot
radio antennas
architecture
urban planning
visibility graph analysis
time series
dynamical systems
graph theory
simple polygon
Hamiltonian graphs
perfect graphs
circle graphs
chordal graphs
cop-win graphs

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