| 1. | A new 2 - d line clipping algorithm
二维线段裁剪新算法 |
| 2. | At last , a 3 - d line - generating algorithm which makes full use of the projections on the 2 - d plane and the symmetry , direction and continuity of the line is presented
最后利用三维直线在二维平面上的投影以及直线的对称性、方向性、连续性，把二维直线生成算法拓展到三维直线，实现了三维空间的直线生成。 |
| 3. | In the new algorithm , spherical surface window is discussed and 3 - d line is divided into two kinds according to comparing the distance from sphere center to line with the radius of sphere
然后，本文首次提出了三维空间球面窗口的线裁剪算法，对球面窗口进行了深入的研究，根据球心到三维线段的距离与球半径的比较，将被裁三维线段分成两大类进行处理。 |
| 4. | One of the two arbitrary planes is formed by the origin and the projected line , which is called the inverse perspective projection plane , the other is perpendicular to the inverse perspective projection plane , and go through the 3 - d line
将其中的一个平面规定为由投影中心和投影直线所确定的平面，称之为反透视投影平面，而另一个平面规定为与反透视投影平面垂直相交且通过空间直线的平面。 |
| 5. | After several decades discussion and exploriation in clipping and line - generating , present algorithms are becoming better and better . but some of them are not perfect . what ' s more , research on 3 - d clipping and 3 - d line - generating is very little
经过了几十年的讨论和探索，尽管现有的裁剪和直线生成算法越来越完善，但有些算法并不是十分理想，而且目前对三维裁剪和三维直线生成算法研究不多。 |
| 6. | At the same time , the second encoding technology is developed to 3 - d clipping and the 3 - d encoding technology presented in this paper is characteristic , that is , by projecting 3 - d line to 2 - d plane we still use 2 - d encoding technology in 3 - d clipping to increase the speed of clipping
同时将二次编码技术从二维裁剪拓展到三维裁剪中，而且本文提出的三维编码思想较具特色，即把被裁三维线段投影到二维平面，仍采用二维编码技术来判断处理，简化了算法，效率较高。 |
| 7. | We consider all kinds of plane line representations of a plane line , and a simple and practical line coordinate system is suggested . we also present a new 3 - d line representation model . the new representation model is based on the geometry theory : the intersection of two arbitrary planes in the 3 - d space is a line in a plane
本文提出了直线坐标的概念，通过分析各种平面直线的表示方法，提出了一套简单而实用的直线坐标表示方法，提出了一种新的空间三维直线表示法，这种表示空间三维直线方法是根据空间相交两平面一般交于一条空间直线的思路而提出的。 |
