Efficient nearest point projection method based on improved Newton iteration

The invention particularly relates to an efficient nearest point projection method based on improved Newton iteration. The method comprises the steps of 1, applying an over-limit interpolation method to an original CAD digital-analog curved surface to obtain three-dimensional space points, and connecting the three-dimensional space points to obtain a three-dimensional grid; 2, discretizing the original CAD digital-analog curved surface, normalizing parameters of the original CAD digital-analog curved surface, and establishing a search tree; 3, searching a discrete point closest to the to-be-projected point by using the search tree, obtaining a clipping ball by taking the distance between the to-be-projected point and the closest discrete point as a radius, and obtaining discrete points searched on a screening surface and a corresponding surface; 4, taking the nearest point of each screened surface as an initial iteration value, and taking the nearest distance point as a final projection point after cyclic alt