关键词: 作物可视化，碰撞检测，碰撞响应，曲面分割，层次包围盒

Abstract: Adopting the collision detection and response methodology into the field of crop growth visualization, an algo- rithm used for collision detection between leaves defined by NURBS (Non Uniform Rational l}Spline)surfaces was pro- posed based on the techniques of surface subdivision and hybrid hierarchical bounding volume (HHBV). Firstly, the leaf surface was subdivided by using the technique of inserting node. Secondly, a HHBV tree for the subdivided leaf based on AABB(Axis Aligned Bounding Box) and FDH(Fixed Direction Hull) was developed. The HHBV tree used AABB as its root node for fast overlap test, and used FDH as other nodes for accurately determine the contact status between leaves in closer proximity. Finally, based on leaf morphological architecture, reasonable and efficient solutions for colli- sion response were presented. Further results proved that the algorithm was efficient for realizing leaves collision simu- lation.

Key words: Crop visualization, Collision detection, Collision response, Surface subdivision, Hierarchical bounding volume