| 摘要 |
PURPOSE:To simplify the arithmetic processing for calculation of a normal vector after sampling of a 3-dimensional model and to shorten the processing time by sampling equidistantly the 3-dimensional model in both X and Y axis directions, obtaining the upper limit sampling value from the coefficient value to be multiplied by the sampling interval, and applying the coefficient value to a prescribed normal vector calculation formula. CONSTITUTION:The upper limit value of a 3-dimensional model is sampled 2-dimensionally and equidistantly in both X and Y axis directions at a sampling interval (m). Then the sampled under limit value is obtained with use of the coefficient value g (i, j) which is multiplied by the sampling interval (m). Furthermore a normal vector N = (nx, ny, nz) of a surface element enclosed by four sampling points adjacent to each other on the upper limit of 3-dimensional model is calculated from an equation I. Thus the arithmetic processing is simplified for calculation of the normal vector after sampling and the processing time is shortened. |
