CMPUT 610 Implementation of a Soft Shadow Algorithm
نویسنده
چکیده
The main objective of this project was to implement the real-time soft shadow volume method proposed by Ulf Assarsson and Thomas Akenine-Möller in their SIGGRAPH 2003 paper [1]. The original method is proposed as a hardware implementation. However due to time constraints, the implementation in this project does not employ a graphics accelerator card for the soft shadow rendering. Fortunately, the features of the approach could still be studied in great depth without a hardware implementation. The original method is one of the first accurate real-time soft shadow rendering methods. Previous methods are either slower, less accurate or less flexible in terms of the shadow casters and receivers. In contrast, Assarsson and Akenine-Möller’s approach is very flexible since it allows arbitrary shadow casters and receivers, and also arbitrary light sources when generalized. The novel idea of the paper uses edges of the object’s silhouette to construct pieces of the shadow penumbra individually. More details follow in the Background section.
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