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:
Jan. 02, 2018
Filed:
Mar. 21, 2017
Google Inc., Mountain View, CA (US);
Teng-Hui Zhu, San Jose, CA (US);
Christopher Craik, Mountain View, CA (US);
Google LLC, Mountain View, CA (US);
Abstract
Methods and apparatus are provided for displaying shadows of circular light sources. A computing device can determine a light source and an occluding polygon that is between the light source and a receiver surface, where the occluding polygon includes vertices connected by edges. The computing device can determine a shadow of the occluding polygon on the receiver surface by at least: determining, for a particular vertex, a projection vertex on the receiver surface by projecting a ray from the center point through the particular vertex; determining an outline polygon based on the projection vertex; determining a projection circle around the projection vertex; determining a penumbra of the shadow based on exterior tangents outside of the outline polygon; and determining an umbra of the shadow based on interior tangents inside the outline polygon. The computing device can display at least part of the shadow.