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Triangulation (geometry)

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is a point set triangulation of a set of two-dimensional points together with elevations for each point. Lifting each point from the plane to its elevated height lifts the triangles of the triangulation into three-dimensional surfaces, which form an approximation of a three-dimensional
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of a point set is a partition of the convex hull of the points into pseudotriangles—polygons that, like triangles, have exactly three convex vertices. As in point set triangulations, pseudotriangulations are required to have their vertices at the given input points.
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as vertices. In order to be suitable as finite element meshes, a triangulation must have well-shaped triangles, according to criteria that depend on the details of the finite element simulation (see
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into triangles meeting edge-to-edge, again with the property that the set of triangle vertices coincides with the set of vertices of the polygon. Polygon triangulations may be found in
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such that they cover the entire surface, the intersection on any pair of subsets is either empty, an edge or a vertex and if the intersection the intersection
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Different types of triangulations may be defined, depending both on what geometric object is to be subdivided and on how the subdivision is determined.
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The concept of a triangulation may also be generalized somewhat to subdivisions into shapes related to triangles. In particular, a
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and form the basis of several important geometric algorithms, including a simple approximate solution to the
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In most instances, the triangles of a triangulation are required to meet edge-to-edge and vertex-to-vertex.
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of any dimension or not at all and such that the set of vertices of the simplices are contained in
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is an adaptation of the Delaunay triangulation from point sets to polygons or, more generally, to
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into triangles, and by extension the subdivision of a higher-dimension geometric object into
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Berg, Mark Theodoor de; Kreveld, Marc van; Overmars, Mark H.; Schwarzkopf, Otfried (2000).
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intersect in a common face (a simplex of any lower dimension) or not at all, and any
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of the points into simplices such that any two simplices intersect in a common
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of a space generally refer to simplicial complexes that are
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Triangulations, Structures for Algorithms and Applications
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Computational geometry: algorithms and applications
60:. Unsourced material may be challenged and removed. 689:is an isometry of the plane on that intersection. 681: 636: 596: 569: 540: 520: 493: 420: 388: 334: 310: 277: 257: 237: 208: 179: 716:. Many meshing techniques are known, including 831:. European Mathematical Society. p. 510. 548:homeomorphic to a non degenerate triangle in 27:Subdivision of a planar object into triangles 8: 682:{\displaystyle f_{\alpha }f_{\beta }^{-1}} 637:{\displaystyle T_{\alpha }\cap T_{\beta }} 670: 665: 655: 649: 628: 615: 609: 588: 582: 561: 557: 556: 553: 533: 512: 506: 486: 412: 411: 409: 380: 376: 375: 365: 364: 362: 327: 302: 298: 297: 294: 270: 250: 229: 225: 224: 221: 200: 196: 195: 192: 172: 120:Learn how and when to remove this message 762: 696:, triangulations are often used as the 501:is a set of subset of compact spaces 7: 731:In more general topological spaces, 58:adding citations to reliable sources 852:Basener, William F. (2006-10-20). 535: 488: 469:constrained Delaunay triangulation 342:. That is, it is a locally finite 25: 18:Triangulation (advanced geometry) 570:{\displaystyle \mathbb {R} ^{2}} 311:{\displaystyle \mathbb {R} ^{d}} 238:{\displaystyle \mathbb {R} ^{d}} 209:{\displaystyle \mathbb {R} ^{d}} 34: 827:Papadopoulos, Athanase (2007). 45:needs additional citations for 829:Handbook of Teichmüller Theory 445:triangulated irregular network 421:{\displaystyle {\mathcal {P}}} 1: 855:Topology and Its Applications 353:, i.e., a triangulation of a 346:that covers the entire space. 69:"Triangulation" geometry 455:is a subdivision of a given 434:minimum-weight triangulation 597:{\displaystyle f_{\alpha }} 521:{\displaystyle T_{\alpha }} 473:planar straight-line graphs 928: 781:. Vol. 25. Springer. 480:triangulation of a surface 396:, is a subdivision of the 912:Triangulation (geometry) 858:. Wiley. pp. 3–14. 722:Chew's second algorithm 541:{\displaystyle \Sigma } 494:{\displaystyle \Sigma } 351:point-set triangulation 683: 638: 598: 571: 542: 522: 495: 430:Delaunay triangulation 422: 390: 336: 312: 279: 259: 239: 210: 181: 140:is a subdivision of a 694:finite element method 684: 639: 599: 572: 543: 523: 496: 453:polygon triangulation 423: 391: 337: 313: 280: 260: 240: 211: 182: 648: 608: 581: 552: 532: 505: 485: 408: 361: 326: 293: 269: 249: 220: 216:is a subdivision of 191: 171: 54:improve this article 750:pseudotriangulation 726:Ruppert's algorithm 720:algorithms such as 718:Delaunay refinement 678: 644:is not empty then 465:art gallery problem 885:Weisstein, Eric W. 771:De Loera, Jesús A. 679: 661: 634: 594: 567: 538: 518: 491: 418: 386: 344:simplicial complex 332: 322:many simplices in 308: 275: 255: 235: 206: 177: 865:978-0-471-68755-9 813:978-3-540-65620-3 775:Santos, Francisco 700:(in this case, a 335:{\displaystyle T} 278:{\displaystyle T} 258:{\displaystyle d} 180:{\displaystyle T} 152:packed together. 130: 129: 122: 104: 16:(Redirected from 919: 898: 897: 870: 869: 849: 843: 842: 824: 818: 817: 799: 793: 792: 773:; Rambau, Jörg; 767: 714:nonobtuse meshes 688: 686: 685: 680: 677: 669: 660: 659: 643: 641: 640: 635: 633: 632: 620: 619: 603: 601: 600: 595: 593: 592: 576: 574: 573: 568: 566: 565: 560: 547: 545: 544: 539: 527: 525: 524: 519: 517: 516: 500: 498: 497: 492: 427: 425: 424: 419: 417: 416: 395: 393: 392: 387: 385: 384: 379: 370: 369: 341: 339: 338: 333: 318:intersects only 317: 315: 314: 309: 307: 306: 301: 284: 282: 281: 276: 264: 262: 261: 256: 244: 242: 241: 236: 234: 233: 228: 215: 213: 212: 207: 205: 204: 199: 186: 184: 183: 178: 167:A triangulation 125: 118: 114: 111: 105: 103: 62: 38: 30: 21: 927: 926: 922: 921: 920: 918: 917: 916: 902: 901: 888:"Triangulation" 883: 882: 879: 874: 873: 866: 851: 850: 846: 839: 826: 825: 821: 814: 801: 800: 796: 789: 769: 768: 764: 759: 746: 651: 646: 645: 624: 611: 606: 605: 584: 579: 578: 555: 550: 549: 530: 529: 508: 503: 502: 483: 482: 406: 405: 374: 359: 358: 324: 323: 296: 291: 290: 267: 266: 247: 246: 223: 218: 217: 194: 189: 188: 169: 168: 161: 126: 115: 109: 106: 63: 61: 51: 39: 28: 23: 22: 15: 12: 11: 5: 925: 923: 915: 914: 904: 903: 900: 899: 878: 877:External links 875: 872: 871: 864: 844: 837: 819: 812: 794: 787: 761: 760: 758: 755: 745: 744:Generalization 742: 741: 740: 733:triangulations 729: 706:Steiner points 690: 676: 673: 668: 664: 658: 654: 631: 627: 623: 618: 614: 591: 587: 564: 559: 537: 515: 511: 490: 476: 449: 437: 415: 383: 378: 373: 368: 357:set of points 347: 331: 305: 300: 274: 254: 232: 227: 203: 198: 176: 160: 157: 128: 127: 42: 40: 33: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 924: 913: 910: 909: 907: 895: 894: 889: 886: 881: 880: 876: 867: 861: 857: 856: 848: 845: 840: 838:9783037190296 834: 830: 823: 820: 815: 809: 805: 798: 795: 790: 788:9783642129711 784: 780: 776: 772: 766: 763: 756: 754: 751: 743: 739:to the space. 738: 734: 730: 727: 723: 719: 715: 711: 707: 703: 702:triangle mesh 699: 695: 691: 674: 671: 666: 662: 656: 652: 629: 625: 621: 616: 612: 589: 585: 562: 513: 509: 481: 477: 474: 470: 466: 462: 458: 454: 450: 446: 442: 438: 435: 431: 403: 399: 381: 371: 356: 352: 348: 345: 329: 321: 303: 288: 272: 252: 230: 201: 174: 166: 165: 164: 158: 156: 153: 151: 147: 143: 142:planar object 139: 138:triangulation 135: 124: 121: 113: 102: 99: 95: 92: 88: 85: 81: 78: 74: 71: –  70: 66: 65:Find sources: 59: 55: 49: 48: 43:This article 41: 37: 32: 31: 19: 891: 854: 847: 828: 822: 803: 797: 778: 765: 747: 737:homeomorphic 710:mesh quality 478:A Euclidean 162: 154: 137: 131: 116: 107: 97: 90: 83: 76: 64: 52:Please help 47:verification 44: 461:linear time 441:cartography 398:convex hull 287:bounded set 757:References 150:tetrahedra 80:newspapers 893:MathWorld 672:− 667:β 657:α 630:β 622:∩ 617:α 590:α 536:Σ 514:α 489:Σ 448:landform. 372:⊂ 146:simplices 906:Category 777:(2010). 355:discrete 320:finitely 134:geometry 110:May 2024 692:In the 457:polygon 94:scholar 862:  835:  810:  785:  467:. 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Index

Triangulation (advanced geometry)

verification
improve this article
adding citations to reliable sources
"Triangulation" geometry
news
newspapers
books
scholar
JSTOR
Learn how and when to remove this message
geometry
planar object
simplices
tetrahedra
bounded set
finitely
simplicial complex
point-set triangulation
discrete
convex hull
face
Delaunay triangulation
minimum-weight triangulation
cartography
triangulated irregular network
polygon triangulation
polygon
linear time

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