论文信息 - Generating Shadows with an Umbra and Penumbra

Generating Shadows with an Umbra and Penumbra

An algorithm for generating shadows with an umbra and penumbra due to distributed light sources is presented. The method used is based on the inclusion of the shadow volumes in the object data processed by a depth-buffer visible surface computation. The standard depth-buffer data structure is modified to allow the handling of shadows with a depth-buffer hidden surface algorithm. The algorithm involves breaking the light source up into a set of point sources and superimposing the shadows generated by each point source to obtain the final shadow. Disciplines Computer Engineering | Computer Sciences Comments University of Pennsylvania Department of Computer and Information Science Technical Report No. MSCIS-84-12. This technical report is available at ScholarlyCommons: http://repository.upenn.edu/cis_reports/1006 GENERATING SHADOWS WITH AN UMBRA AND PENUMBRA Lynne Shapiro Norman I. Badler MS.CIS-84-12 Department of Computer and Information Science Moore School/D2 University of Pennsylvania Philadelphia, P A 19104

Norman I. Badler | Lynne Shapiro

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