@InProceedings {felkel99sccg, UPDATE = { 2003-12-12 }, author = { Felkel Petr and Obdr{\v z}{\' a}lek, {\v S}t{\v e}p{\' a}n }, title = { Improvement of Oliva's Algorithm for Surface Reconstruction from Contours }, year = { 1999 }, booktitle = { SCCG 99: Proceedings of the 15th Spring Conference on Computer Graphics }, pages = { 254--263 }, editor = { Ji{\v r}{\' i} {\v Z}{\' a}ra }, publisher = { Comenius University. Bratislava }, month = { 4--5 }, day = { 28--1 }, venue = { Budmerice, Slovakia }, isbn = { 80--223--1357--2 }, annote = { Oliva proposed an interesting algorithm for a 3D surface reconstruction from contours in parallel cross-sections. As stated in the article [9], the algorithm constructs the surface for any non-self-intersecting contour shape also with holes [9] by means of adding appropriate number of intermediate cross-sections between complicated contours and triangulation of every pair of contours in different slices separately. For this task a Straight skeleton (Angular Bisector Network) [1, 9] is exploited. We have implemented Oliva's algorithm and we have found cases, which are not handled properly. The resulting surface can contain overhangs and self-intersected triangles can occur. We propose a modification of a triangulation step in Oliva's algorithm which handles differently the cases when overhangs (artifacts looking like folds) can appear and generates an overhang-free surface. By excluding overhangs we prevent also the creation of degenerated surface with mutually-intersected triangles. }, authorship = { 50-50 }, psurl = { felkel.ps.gz [compressed postscript, 26 kB] }, }