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Triangulated irregular network

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28: 20: 282:(Voronoi) polygon generation can only be performed on Delaunay conforming triangulations. A constrained Delaunay triangulation can be considered when you need to explicitly define certain edges that are guaranteed not to be modified (that is, split into multiple edges) by the triangulator. Constrained Delaunay triangulations are also useful for minimizing the size of a TIN, since they have fewer nodes and triangles where breaklines are not densified. 281:
or constrained Delaunay. Delaunay conforming triangulations are recommended over constrained triangulations. This is because the resulting TINs are likely to contain fewer long, skinny triangles, which are undesirable for surface analysis. Additionally, natural neighbor interpolation and Thiessen
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that determines which points are most necessary to create an accurate representation of the terrain. Data input is therefore flexible and fewer points need to be stored than in a raster DEM, with regularly distributed points. While a TIN may be considered less suited than a raster DEM for certain
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The TIN model was developed in the early 1970s as a simple way to build a surface from a set of irregularly spaced points. The first triangulated irregular network program for GIS was written by W. Randolph Franklin, under the direction of David Douglas and Thomas Peucker (Poiker), at Canada's
243:. Three-dimensional visualizations are readily created by rendering of the triangular facets. In regions where there is little variation in surface height, the points may be widely spaced whereas in areas of more intense variation in height the point density is increased. 73:
The vertices of these triangles are created from field recorded spot elevations through a variety of means including surveying through conventional techniques, Global Positioning System Real-Time Kinematic (GPS RTK),
224: 116: 156: 254:(DEM), which can be further used to produce digital surface models (DSM) or digital terrain models (DTM). An advantage of using a TIN over a 405: 274:, it is often used in CAD to create contour lines. A DTM and DSM can be formed from a DEM. A DEM can be interpolated from a TIN. 51: 354: 400: 395: 168: 67: 184: 317: 380: 179:-based representation of the physical land surface or sea bottom, made up of irregularly distributed 370: 287: 258: 251: 278: 261:(DEM) in mapping and analysis is that the points of a TIN are distributed variably based on an 191: 172: 83: 55: 129: 63: 8: 231:
A TIN comprises a triangular network of vertices, known as mass points, with associated
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A variety of different file formats exist for saving TIN information, including
75: 27: 389: 59: 240: 175:(CAD) for the visual representation of a topographical surface. A TIN is a 32: 232: 124:, TINs are useful for the description and analysis of general horizontal 19: 255: 236: 121: 262: 16:
Representation of a surface as a triangle mesh with elevated vertices
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Franklin, W. R. (1973). Triangulated irregular network program.
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that are arranged in a network of non-overlapping triangles.
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kinds of GIS applications, such as analysis of a surface's
78:, or some other means. Associated with three-dimensional 194: 132: 86: 302:, along with others such as AquaVeo and ICEM CFD. 218: 150: 110: 167:are used in a variety of applications, including 387: 320:Also known as a "Triangular Irregular Network" 58:consisting entirely of triangular facets (a 239:connected by edges to form a triangular 26: 18: 388: 13: 14: 417: 364: 160:distributions and relationships. 406:Geographic data and information 293: 347: 333: 324: 311: 213: 195: 169:geographic information systems 145: 133: 105: 87: 44:triangulated irregular network 23:Triangulated irregular network 1: 305: 185:three-dimensional coordinates 7: 10: 422: 68:primary elevation modeling 401:Geometric data structures 396:Triangulation (geometry) 246:A TIN used to represent 288:Simon Fraser University 259:digital elevation model 252:digital elevation model 219:{\displaystyle (x,y,z)} 111:{\displaystyle (x,y,z)} 341:"TIN Files - XMS Wiki" 279:Delaunay triangulation 220: 152: 112: 35: 24: 221: 173:computer aided design 153: 151:{\displaystyle (x,y)} 113: 30: 22: 192: 130: 84: 64:Discrete Global Grid 277:TIN are based on a 250:is often called a 216: 148: 108: 62:), used mainly as 36: 31:TIN overlaid with 25: 40:computer graphics 413: 359: 358: 351: 345: 344: 337: 331: 328: 322: 315: 227: 225: 223: 222: 217: 159: 157: 155: 154: 149: 119: 117: 115: 114: 109: 54:of a continuous 421: 420: 416: 415: 414: 412: 411: 410: 386: 385: 367: 362: 353: 352: 348: 339: 338: 334: 329: 325: 316: 312: 308: 296: 193: 190: 189: 187: 183:and lines with 165:data structures 131: 128: 127: 125: 85: 82: 81: 79: 17: 12: 11: 5: 419: 409: 408: 403: 398: 384: 383: 378: 373: 366: 365:External links 363: 361: 360: 346: 332: 323: 309: 307: 304: 295: 292: 215: 212: 209: 206: 203: 200: 197: 147: 144: 141: 138: 135: 107: 104: 101: 98: 95: 92: 89: 76:photogrammetry 52:representation 15: 9: 6: 4: 3: 2: 418: 407: 404: 402: 399: 397: 394: 393: 391: 382: 379: 377: 376:PSU Education 374: 372: 371:UBC Geography 369: 368: 356: 350: 342: 336: 327: 321: 318: 314: 310: 303: 301: 291: 290:, in 1973. 289: 283: 280: 275: 273: 269: 264: 260: 257: 253: 249: 244: 242: 238: 234: 229: 210: 207: 204: 201: 198: 186: 182: 178: 174: 170: 166: 161: 142: 139: 136: 123: 102: 99: 96: 93: 90: 77: 71: 69: 65: 61: 60:triangle mesh 57: 53: 49: 45: 41: 34: 33:contour lines 29: 21: 349: 335: 326: 313: 297: 294:File formats 284: 276: 245: 241:tessellation 230: 163:Digital TIN 162: 72: 47: 43: 37: 233:coordinates 171:(GIS), and 390:Categories 306:References 256:rasterized 237:dimensions 122:topography 263:algorithm 235:in three 120:data and 300:Esri TIN 248:terrain 226:⁠ 188:⁠ 158:⁠ 126:⁠ 118:⁠ 80:⁠ 56:surface 50:) is a 381:ArcGIS 272:aspect 177:vector 268:slope 181:nodes 270:and 42:, a 66:in 48:TIN 38:In 392:: 70:. 357:. 343:. 214:) 211:z 208:, 205:y 202:, 199:x 196:( 146:) 143:y 140:, 137:x 134:( 106:) 103:z 100:, 97:y 94:, 91:x 88:( 46:(

Index



contour lines
computer graphics
representation
surface
triangle mesh
Discrete Global Grid
primary elevation modeling
photogrammetry
topography
data structures
geographic information systems
computer aided design
vector
nodes
three-dimensional coordinates
coordinates
dimensions
tessellation
terrain
digital elevation model
rasterized
digital elevation model
algorithm
slope
aspect
Delaunay triangulation
Simon Fraser University
Esri TIN

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