| Between umbra and penumbra (2008) | |||||||||||||||
Abstract | |||||||||||||||
| Computing shadow boundaries is a difficult problem in the case of non-point light sources. A point is in the umbra if it does not see any part of any light source; it is in full light if it sees entirely all the light sources; otherwise, it is in the penumbra. While the common boundary of the penumbra and the full light is well-understood, less is known about the boundary of the umbra. In this paper we present various bounds on the complexity of the umbra cast by a segment or polygonal light source on a plane in the presence of polygon or polytope obstacles. 1 | |||||||||||||||
Publication details | |||||||||||||||
| |||||||||||||||