Qi Di, Milef Nicholas, De Suvranu
Center for Modeling, Simulation and Imaging in Medicine, Rensselaer Polytechnic Institute.
Department of Computer Science & Engineering, Texas A&M University.
Vis Comput. 2021 May;37(5):1113-1127. doi: 10.1007/s00371-020-01856-y. Epub 2020 May 20.
Efficient algorithms that support dynamic topological updates are necessary for the simulation of progressive interactive cutting of deformable objects. Existing mesh-based techniques suffer from the generation of ill-shaped elements whereas voxel grid-based methods require additional cut surfaces to be generated or the use of look-up tables for pre-computed cutting patterns. To overcome these limitations of existing methods, we propose a novel voxel-based topological operator, , which divides a voxel into two voxels identical to the original voxel's size by dynamically distributing its voxel elements (nodes, edges) into the newly divided voxels until the cutting of the original voxel is completed. The connectivity between the divided voxels and the neighbors of the original voxel is retained during the cut, and new connectivity between the adjacent divided voxels is generated to represent the continuity of the cut. As a result, the cut surface can be generated directly from the divided voxels on-the-fly, and the correspondence between the cut surface and the simulation voxels is maintained without any additional effort. We use several example problems to demonstrate the efficiency of our method and compare it with other existing approaches.
对于可变形物体的渐进交互式切割模拟而言,支持动态拓扑更新的高效算法是必不可少的。现有的基于网格的技术存在生成形状不良元素的问题,而基于体素网格的方法则需要生成额外的切割表面或使用预计算切割模式的查找表。为了克服现有方法的这些局限性,我们提出了一种新颖的基于体素的拓扑算子,它通过将其体素元素(节点、边)动态分布到新分割的体素中,直到原始体素的切割完成,从而将一个体素分割成两个与原始体素大小相同的体素。在切割过程中,分割后的体素与原始体素的邻居之间的连通性得以保留,并且相邻分割体素之间会生成新的连通性以表示切割的连续性。结果,可以直接从分割后的体素即时生成切割表面,并且无需任何额外努力即可保持切割表面与模拟体素之间的对应关系。我们使用几个示例问题来证明我们方法的效率,并将其与其他现有方法进行比较。