Interactive Rendering of Trees with Shading and Shadows

Alexandre Meyer Fabrice Neyret and Pierre Poulin
Proc. Eurographics Workshop on Rendering 2001, June 2001

Abstract

The goal of this paper is the interactive rendering of 3D trees covering a landscape, with shading and shadows consistent with the lighting conditions. We propose a new IBR representation, consisting of a hierarchy of Bidirectional Textures, which resemble 6D lightfields. A hierarchy of visibility cube-maps is associated to this representation to improve the performance of shadow calculations. An example of hierarchy for a given tree can be a small branch plus its leaves (or needles), a larger branch, and the entire tree. A Bidirectional Texture (BT) provides a billboard image of a shaded object for each pair of view and light directions. We associate a BT for each level of the hierarchy. When rendering, the appropriate level of detail is selected depending on the distance of the tree from the viewpoint. The illumination reaching each level is evaluated using a visibility cube-map. Thus, we very efficiently obtain the shaded rendering of a tree with shadows without loosing details, contrary to mesh simplification methods. We achieved 7 to 20 fps fly-throughs of a scene with 1000 trees.

Keywords

Real-time rendering, natural scenes, forests, IBR, levels of detail, billboards.

BibTeX entry

@inproceedings{MNP-egwr2001,
  title     = "Interactive Rendering of Trees with Shading and Shadows",
  author    = "Alexandre Meyer, Fabrice Neyret, and Pierre Poulin",
  booktitle = "Eurographics Workshop on Rendering 2001",
  year      = "2001",
  month     = "June",
  pages     = "-"
}

Online version

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