Patent
1994-02-28
1997-05-13
Jankus, Almis R.
395133, 395123, G06T 1100
Patent
active
056300395
ABSTRACT:
A computer graphics system, that manipulates the vertices contained within a group of possibly self intersecting, free space, over lapping polygons, into simple, convex polygons. A normal axis to the complex polygon is determined such that the surface of the polygon is viewed along this normal axis. The polygon surface is then bounded by a rectangle and subdivided into a group of slabs, or smaller rectangles, each rectangular slab being bounded by a pair of interior vertices of the complex polygon. An active edge table is used to store values corresponding to the edges crossing through the slabs, which are used to determine if these edges cross are another at any point within the slab. If a crossing point does exist, the slabs are divided at the crossing point into rectangular sub-slabs until it is determined that no edge intersects another edge within the sub-slabs, of the original slab being considered. At this point, the edges contained within the rectangular slabs can be viewed as simple polygons, or trapezoids which can be filled by a conventional graphics adapter and then displayed.
REFERENCES:
patent: 3816726 (1974-06-01), Sutherland et al.
patent: 4709231 (1987-11-01), Sakaibara et al.
patent: 4710876 (1987-12-01), Cline et al.
patent: 4715005 (1987-12-01), Heartz
patent: 4812988 (1989-03-01), Duthuit et al.
patent: 4815009 (1989-03-01), Blatin
patent: 4841292 (1989-06-01), Zeno
patent: 4855934 (1989-08-01), Robinson
patent: 4855938 (1989-08-01), Gonzalez-Lopez et al.
patent: 4912659 (1990-03-01), Liang
Harrington et al., Interpress the Source Book (1988) pp. 197-199.
Computers & Graphics, vol. 11, No. 4, 1987, GB, XP115892, "A Note on Multi-Polygon Area Filing", Rankin.
Patent Abstract of Japan, vol. 850, No. 831 (P-384) Apr. 26, 1985, & JP-A-60 074 086, K. K. Fujitsu, abstract.
IBM Technical Disclosure Bulletin, "Hardware Manipulation of Three-Dimensional Graphics" vol. 14, No. 12, May 1972.
D. Gordon, R. A. Reynolds, Dept. of Radiology, University of Penn., "Image Space Shading of Three-Dimensional Objects", Nov. 1983.
A. C. Tan, R. Richards, Medical Information, "Pseudoshading technique in the two-dimensional domain: a post-processing algorithm for enhancing the Z-buffer of a three-dimensional binary image" vol. 14, No. 2, pp. 149-156, 1989.
Dillon Andrew J.
International Business Machines - Corporation
Jankus Almis R.
Tyson Thomas E.
LandOfFree
Tessellating complex in polygons in modeling coordinates does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tessellating complex in polygons in modeling coordinates, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tessellating complex in polygons in modeling coordinates will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1392589