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Approximate soft shadows on arbitrary surfaces using Penumbra wedges

Akenine-Möller, Tomas LU and Assarsson, Ulf (2002) 13th Eurographics Workshop on Rendering 2002 In ACM International Conference Proceeding Series 28. p.297-306
Abstract
Shadow generation has been subject to serious investigation in computer graphics, and many clever algorithms have been suggested. However, previous algorithms cannot render high quality soft shadows onto arbitrary, animated objects in real time. Pursuing this goal, we present a new soft shadow algorithm that extends the standard shadow volume algorithm by replacing each shadow quadrilateral with a new primitive, called the penumbra wedge. For each silhouette edge as seen from the light source, a penumbra wedge is created that approximately models the penumbra volume that this edge gives rise to. Together the penumbra wedges can render images that often are remarkably close to more precisely rendered soft shadows. Furthermore, our new... (More)
Shadow generation has been subject to serious investigation in computer graphics, and many clever algorithms have been suggested. However, previous algorithms cannot render high quality soft shadows onto arbitrary, animated objects in real time. Pursuing this goal, we present a new soft shadow algorithm that extends the standard shadow volume algorithm by replacing each shadow quadrilateral with a new primitive, called the penumbra wedge. For each silhouette edge as seen from the light source, a penumbra wedge is created that approximately models the penumbra volume that this edge gives rise to. Together the penumbra wedges can render images that often are remarkably close to more precisely rendered soft shadows. Furthermore, our new primitive is designed so that it can be rasterized efficiently. Many real-time algorithms can only use planes as shadow receivers, while ours can handle arbitrary shadow receivers. The proposed algorithm can be of great value to, e.g., 3D computer games, especially since it is highly likely that this algorithm can be implemented on programmable graphics hardware coming out within the next year, and because games often prefer perceptually convincing shadows. (Less)
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author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
in
ACM International Conference Proceeding Series
volume
28
pages
297 - 306
conference name
13th Eurographics Workshop on Rendering 2002
external identifiers
  • Scopus:0036980309
ISBN
1-58113-534-3
language
English
LU publication?
yes
id
a6f59296-218a-42e0-abb8-c4d38067a55c (old id 747742)
alternative location
http://portal.acm.org/citation.cfm?id=581935
date added to LUP
2008-01-21 12:41:49
date last changed
2017-01-01 08:11:05
@inproceedings{a6f59296-218a-42e0-abb8-c4d38067a55c,
  abstract     = {Shadow generation has been subject to serious investigation in computer graphics, and many clever algorithms have been suggested. However, previous algorithms cannot render high quality soft shadows onto arbitrary, animated objects in real time. Pursuing this goal, we present a new soft shadow algorithm that extends the standard shadow volume algorithm by replacing each shadow quadrilateral with a new primitive, called the penumbra wedge. For each silhouette edge as seen from the light source, a penumbra wedge is created that approximately models the penumbra volume that this edge gives rise to. Together the penumbra wedges can render images that often are remarkably close to more precisely rendered soft shadows. Furthermore, our new primitive is designed so that it can be rasterized efficiently. Many real-time algorithms can only use planes as shadow receivers, while ours can handle arbitrary shadow receivers. The proposed algorithm can be of great value to, e.g., 3D computer games, especially since it is highly likely that this algorithm can be implemented on programmable graphics hardware coming out within the next year, and because games often prefer perceptually convincing shadows.},
  author       = {Akenine-Möller, Tomas and Assarsson, Ulf},
  booktitle    = {ACM International Conference Proceeding Series},
  isbn         = {1-58113-534-3},
  language     = {eng},
  pages        = {297--306},
  title        = {Approximate soft shadows on arbitrary surfaces using Penumbra wedges},
  volume       = {28},
  year         = {2002},
}