局部各向异性的薄壳收缩变形

Local Anisotropic Contraction Deformation of Thin Shell

基于位置动力学提出局部各向异性的薄壳收缩变形方法.首先针对基于位置动力学变形模拟方法的材质局限性的不足,提出薄壳收缩变形的弹性变形能,实现了多材质的弹性收缩变形.其次,针对薄壳收缩变形过程中的抖动问题,给出适当的弯曲能系数,实现了稳定的收缩变形.第三,针对薄壳局部类球面结构收缩变形缓慢且细微的不足,定义了局部各向异性ARAP变形能等,实现了薄壳局部类球结构的快速、显著、稳定的收缩变形.最后以轴向平行包围盒与非渗透滤波器作为碰撞检测的预处理,剔除不可能发生碰撞的图元对,提高了收缩变形过程中的碰撞检测效率.相关实验结果表明,提出的薄壳收缩变形算法适用于多种材质模型以及多种各向异性能量,且有效地解决了抖动及局部类球结构收缩变形缓慢且不显著等问题.

A novel algorithm is proposed for local anisotropic contraction deformation on thin shell using the framework of position-based dynamics.Firstly,a new elastic deformation energy of thin shell is presented to address the material limitation of position-based dynamics,and get desired elastic contraction deformation on a variety of materials.Secondly,a stable contraction deformation is abstained without jittering by giving a proper coefficient of bending energy.Thirdly,a local anisotropic ARAP deformation energy is defined to produce a rapid and stable invagination on the area of the local spherical structures where the deformation is slow and slight.Finally,the axis-aligned bounding box and the non-penetration filters are used as a preprocess stage in order to cull the primitive pairs that are impossible to collide,to accelerate the speed of collision detection.The experimental results demonstrate that,the proposed method supports many different types of materials and local anisotropic energies,and can work with the problems of jittering and the slight deformation on local spherical structures.