A PROCEDURE FOR AUTOMATICALLY CORRECTING INVALID FLAT TRIANGLES OCCURRING IN TRIANGULATED CONTOUR DATA

Constrained Delaunay triangulation is used widely as a basis for trian gulating contour data. However, this method frequently produces triang ulations that include flat triangles (i.e. where the three vertices of a triangle lie on the same contour). In many situations, such triangl es fail to reflect the true shape of the surface being modelled. This paper presents details of a procedure, termed flat triangle corrector, which automatically corrects invalid flat triangles and produces a mo re accurate surface approximation. A detailed description of the proce dure is provided in the form of a commentary and pseudo-code listing. Experimental results on digitised contour data demonstrate that the ap proach is successful in correcting all Aat triangles in a series of tr iangulations, (C) 1998 Elsevier Science Ltd. All rights reserved.