实时刚体破碎特效仿真研究

Real-Time Rigid Body Fracturing Simulation

刚体仿真是图形学研究的热点之一,但是单纯依据物理规律进行仿真达不到实时性要求.依据攻击武器的运动轨迹在目标的八叉树结构上抽取空间连续的子块,设计了一种摧毁区域锁定算法;提出一种刚体预破碎模式,采用线性约束连接子块和块内元素,并用统一的算法检测由攻击武器的碰撞引起的约束动态受损情况.线性约束的不同程度破损或导致子块的分裂,或导致块内基础元素的分裂,将形成不同程度的破碎特效.最后设计了实时刚体破碎特效实验方案并构建仿真系统.实验表明,该种模式不仅较好地体现了刚体破碎特效,也简化了刚体破碎仿真的复杂性,相应的破碎特效能够拓展到具有实时性需求的虚拟现实应用环境中.

Rigid body dynamics has been of great interest to the computer graphics researchers for a long time,especially during the latest decade. Purely physical based simulation is not a good solution for the virtual reality application environment because of its low real-time feature; researchers have to balance the simulation speed and the visual effect. Based on the attacker＇s track,an effect algorithm for locking to-be destroyed area is designed. Octree is used to structure the target＇s geometry model,and then spatial continual subsets in the local area are extracted according to the attacker＇ collision position. A pre-fracturing pattern for rigid body simulation is proposed in this paper. Linear constraints are used to connect the subsets and their fundamental elements. At the same time the whole local area and the other part of the target are connected by the linear constraints too. A unified algorithm will detect how the constraints are impacted,which will lead to fracture effect. Once the constraint is broken,the subsets or the elements will be separated. Different attackers will lead to different levels of fracture. The key reason is that the linear constraint impacted is dynamic due to the attackers＇ collision degree. Finally,a real time rigid body fracturing effect simulation system is designed. Experiments show that the pattern works well and predigests some complexity,and it could be applied in the virtual reality environment requiring real-time feature.