New 3D line clipping algorithm against spherical surface window

A new method for 3D(three dimensional) line clipping against spherical surface window is presented. The new approach will play an important role in 3D clothing design and clipping. To reduce the times of judgment of the correlativity between lines and the spherical surface window, a new concept of projecting encoding is put forward. By projecting the circumscribed-cube and the circumscribed- dodecahedron of the spherical surface window to the 2D(two dimensional) coordinate system respective, 3D line clipping can be simplified to 2D line clipping, then six-figure code of the line which to be clipped can be simplified to four-figure code. What is more significant, most of the line segments that are completely outside of the window can be quickly discarded by projecting encoding. At the same time, Comparing the generalized distance and generalized height with the radius of sphere, all the line segments that are completely inside of the window and the remaining lines that are outside of the window can also be quickly identified. At last, the efficiency of the new algorithm established in this paper is compared with the efficiency of the common method. Experiment results show that the new algorithm has a higher efficiency and a better stability.