公开(公告)号：US5040130A

公开(公告)日：1991-08-13

申请号：US520161

申请日：1990-05-07

申请人： Fu-Chung Chang ,  James A. Donnelly ,  Richard A. Marino ,  Terence W. Lindgren

发明人： Fu-Chung Chang ,  James A. Donnelly ,  Richard A. Marino ,  Terence W. Lindgren

IPC分类号： G06T15/30

CPC分类号： G06T15/30

摘要： A method for clipping a line segment boundary-defined area against a limiting plane is disclosed for use in a computer graphics display system wherein graphics figures are represented by random sets of polylines definitive of line segment boundary-defined areas. Pursuant to the clipping method, once two intersection points are generated against one plane, the points are connected to form an edge of the new clipped boundary-defined area. The order of intersection point connection is irrelevant to the invention and the method can accomodate discontinuously presented data as readily as continuously presented data. Implementing the method essentially requires only one register to store the first intersection point and a flag register to indicate the status of the present clip point, i.e., whether the clipped point is the first or second of two points to be paired. In another aspect of the invention, an improved extraneous edge deletion method is provided capable of deleting extraneous lines formed as a result of a line segment boundary-defined area being clipped against a limiting plane. Pursuant to the method, clipped X-axis and Y-axis extraneous edges are eliminated during area fill processing in the graphics display system.

摘要翻译： 公开了一种用于限制针对限制平面限制线段边界限定区域的方法，用于计算机图形显示系统中，其中图形图形由线段边界限定区域的多边形的随机组表示。 根据裁剪方法，一旦相对于一个平面产生两个交点，这些点被连接以形成新的剪切边界定义区域的边缘。 交叉点连接顺序与本发明无关，该方法可以容纳不间断呈现的数据。 实现该方法基本上仅需要一个寄存器来存储第一交点和标志寄存器来指示当前剪辑点的状态，即剪辑点是否是要配对的两个点中的第一或第二。 在本发明的另一方面，提供一种改进的外来边缘删除方法，其能够删除由于线段边界限定区域被限制在限制平面上而形成的外来线。 根据该方法，在图形显示系统的区域填充处理期间消除了夹持的X轴和Y轴的外部边缘。