An Algorithm for Reconstruction of Surface from Parallel Contours and Its Section Contour Extraction in any Cutting Plane

To obtain reconstruction of surfaces from a given contours stack, this paper presents a new algorithm based on MC-algorithm, which solves the problem that 3D surface model cannot be built because the first/last contour has no previous/next contour information, or there are only isolated contours. Meanwhile, the algorithm is applied to extracting section contour of the 3D model in any cutting plane. The algorithm does not need to do as following: traverse and rebuild each triangle of the 3D model, obtain the points of intersection with the cutting plane, and link all points of intersection to get the contour in cutting plane. The algorithm divides the cutting plane into rectangular grid and gets isoline in each marching rectangle directly, without considering the problem of connections of all points of intersection. The 2D sectional contour can be obtained directly after finishing calculating isoline in the rectangular grid.