Wind projection basis for real-time animation of trees

Julien Diener (1) , Mathieu Rodriguez (2, 3) , Lionel Baboud (4) , Lionel Reveret (1)

1 EVASION - Virtual environments for animation and image synthesis of natural objects
2 LadHyX - Laboratoire d'hydrodynamique
3 PIAF - Laboratoire de Physique et Physiologie Intégratives de l'Arbre Fruitier et Forestier
4 ARTIS - Acquisition, representation and transformations for image synthesis

This scientific report presents a real-time method to animate complex scenes of thousands of trees under a user-controllable wind load. Firstly, modal analysis is applied to extract the main modes of deformation from the mechanical model of a 3D tree. The novelty of our contribution is to precompute a new basis of the modal stress of the tree under wind load. At runtime, this basis allows to replace the modal projection of the external forces by a direct mapping for any directional wind. We show that this approach can be efficiently implemented on a graphics hardware. This modal animation can be simulated at low computation cost even for large scenes containing thousands of trees.

Mots clés: Animation; physical simulation; tree; modal analysis; real-time

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

Julien Diener, Mathieu Rodriguez, Lionel Baboud, Lionel Reveret. Wind projection basis for real-time animation of trees. [Research Report] RR-6674, 2008, pp.20. ⟨inria-00328122v1⟩