Abstract: The problems with the traditional surface segmentation intersection lie in the choice of plane, loss of intersection line and discontinuous intersection line. In view of these problems, this paper proposes a surface segmentation intersection algorithm based on spatial polygon triangulation. The algorithm based on equal depth segmentation avoids the problem of discontinuous intersection line. When the segmentation reaches a certain level, the spatial polygon is used to approximate the surface patch, and the spatial polygon is triangulated. The intersection of the triangular pair is similar to the intersection between the spatial polygons, then the intersection of the spatial polygons is approximated to the intersection of the patches. Finally we get intersection lines between the intersection surfaces. The spatial polygons constructed by the contours of the surface patch are closer to the true shape of the patch, and the approximation accuracy is improved. The triangulation of the spatial polygons improves the accuracy of the intersection, thus reducing the possibility of losing the intersection line. In theory, this algorithm is more accurate than the traditional segmentation method, and the experiment also verifies this conclusion.

Key words: segmentation method, spatial polygon, triangulation