Patent ID: 8805908
Filing Date: 2014-08-12
Classification: G06T

Abstract:
1. An approximation processing method for approximating data points of a point group using a curve or a surface defined by control points, said approximation processing method, executed by a computer according to a program stored in the computer, comprising: a simplification step of forming an initial approximated curve or an initial approximated surface using initial control points that are simplified by a geometrical algorithm; a step of forming an approximated curve or an approximated surface using control points that retain features of a shape from the initial approximated curve or the initial approximated surface; a first calculation step of calculating a closest point closest to each of the data points on the approximated curve or the approximated surface; a second calculation step of calculating an error vector that joins the closest point, obtained in said first calculation step, to the data point; and a third calculation step of calculating a corrected control point by moving each of the control points based on the error vector obtained by said second calculation step wherein said step of forming an approximated curve or an approximated surface and said calculation steps are performed by operation means in which the geometrical algorithm is included, said step of forming an approximated curve or an approximated surface and said first to third calculation steps are repeated to make the approximated curve or the approximated surface respectively approximate the curve or the surface of an object configured by the data points, and said third calculation step performs weighting processing for error vectors that are a plurality of error vectors calculated by said second calculation step and that are calculated for closest points around a control point to be corrected, adds up the weighted error vectors through vector addition, moves the control point with the added vector, generated by adding up the vectors, as a motion vector, and calculates the moved control point as the corrected control point.