Realistic soft shadows by penumbra-wedges blending

Vincent Forest (1) , Loic Barthe (2) , Mathias Paulin (2)

1 IRIT - Institut de recherche en informatique de Toulouse
2 IRIT-VORTEX - Visual Objects from Reality To Expression

Recent real-time shadow generation techniques try to provide shadows with realistic penumbrae. However, most techniques are whether non-physically based or too simplified to produce convicing results. The penumbra-wedges algorithm is a physical approach based on the assumption that penumbrae are non-overlapping. In this paper, we propose an algorithm that takes the advantages of the penumbra-wedges method but solves the "non-overlapping" limitation. We first compute the light occlusion regions per fragment. Then we use this information to detect the areas where penumbrae are overlapping and we perform a realistic penumbra blending.

Domaines: Synthèse d'image et réalité virtuelle [cs.GR]

Vincent Forest, Loic Barthe, Mathias Paulin. Realistic soft shadows by penumbra-wedges blending. ACM SIGGRAPH/EUROGRAPHICS symposium on Graphics hardware, Sep 2006, Vienna, Austria. pp.39 - 46, ⟨10.1145/1283900.1283907⟩. ⟨hal-01518551⟩