|
Michael Schwarz (FAU) and Marc Stamminger (FAU)
Presented at EUROGRAPHICS 2007 in September in Prague -Publication in the journal
"Computer Graphics Forum" (volume 26, issue 3)
EG 07 conference website
Abstract
Recently, several real-time soft shadow algorithms have been introduced
which all compute a single shadow map and use its texels to obtain a
discrete scene representation. The resulting micropatches are
backprojected onto
the light source and the light areas occluded by them get accumulated
to estimate overall light occlusion. This approach ignores patch
overlaps, however, which can lead to objectionable artifacts. In this
paper, we propose to determine the visibility of the light source with
a bit field where each bit tracks the visibility of a sample point on
the light source. This approach not only avoids overlapping-related
artifacts but offers a solution to the important occluder fusion
problem. Hence, it also becomes possible to correctly incorporate
information from multiple depth maps. In addition, a new interpretation
of the shadow map data is suggested which often provides superior
visual results. Finally, we show how the search area for potential
occluders can be reduced substantially.
|
CROSSMOD is a Specific Targeted Research Project partly funded by EU within the 6th Framework Programme.