建立DTM时顾及地形线的辐射旋转法

RADIAL SWEEP METHOD FOR ESTABLISHING DTMWITH TOPOGRAPHICAL LINES CONCERNED

: Over the last ten years, there has been considerable progress in the modelling of complex surface by computer. Surface modelling techniques have often been used to interpolate contours and to calculate land volumes. Two methods are often used in the modelling of irregular surface, i.e. triangulated irregular networks (TIN) and rectangular grids (RG). In the process of establishing digital terrain model (DTM), among all the problems, the more difficult one to be solved is how to represent uncontinuity, such as break layer, which is often existed in mine maps as well as in other topographical con tour or 3-D maps. After a brief review of the TIN and RG models, there advantages and disadvantages are compared in this paper. The principles of the radial sweep method adopted by the authors are discussed in detail. Finally, the application prospect and developing direction of DTM are also discussed.