3816726 is referenced by 92 patents and cites 2 patents.

A system is disclosed for clipping three-dimensional polygons for use in a computer-graphics display. The system removes from each polygon all parts that lie outside an arbitrary, plane-faced, convex polyhedron, e.g. a truncated pyramid defining a viewing volume. The polygon is defined by data representing a group of vertices and is clipped separately in its entirety against each clipping plane (of the polyhedron). In a multiple-stage structure as disclosed, each stage clips the polygon against a single plane and requires storage for only two vertex values. A time-sharing embodiment of the system is also disclosed. The disclosed system also incorporates the use of a perspective transformation matrix which provides for arbitrary field-of-view angles and depth-of-field distances while utilizing simple, fixed clipping planes.

Computer graphics clipping system for polygons
Application Number
Publication Number
Application Date
October 16, 1972
Publication Date
June 11, 1974
Hodgman Gary W
Sutherland Ivan E
Nilsson Robbins & Berliner
Evans & Sutherland Computer
G06f 15/20
G06f 07/38
G06T 15/40
G09G 01/06
G06T 15/10
View Original Source