The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 18, 1999
Filed:
Sep. 03, 1996
David E Penna, Redhill, GB;
U.S. Philips Corporation, New York, NY (US);
Abstract
A 3-D image synthesis apparatus maintains an 'object database' (OBJ) defining a 3-D world to be represented on a 2-D display screen (DIS). The object database includes light sources (LS) which have non-uniform distributions of illumination. To simplify calculations of the illumination of an object surface (P.sub.O), the apparatus pre-stores (606) one or more look-up tables. The look-up table (606) is then addressed by polar coordinates (.theta.,.phi.) calculated per pixel of the output image, to incorporate the dependency of illumination on direction. Several tables may be stored for each light source, each representing the illumination pattern at a different distance (D) from the light source. Smooth variations can be achieved by interpolation between integer values of .theta.,.phi. and D.