Progressing Level-of-Detail Animation for Volumetric Elastodynamics

摘要

We extend Progressive Dynamics [Zhang et al. 2024, 2025] from cloth and shells to volumetric finite elements, enabling an efficient level-of-detail (LOD) animation-design pipeline with predictive coarse-resolution previews for rapid iteration toward a final high-resolution volumetric elastodynamics animation. To achieve this, we introduce VelPro Splitter, a principled and substantially improved VelPro-type integrator [Zhang et al. 2025] that splits the current-level velocity and recombines its high-resolution component with prolonged coarse-level velocity. The resulting VelPro Splitter is general and applies to both shell and volumetric discretizations. This splitting strategy better generates the high-frequency dynamic details that motivate highresolution elastodynamics animation, going beyond the previously mostly geometric enrichment due to prolonged coarse-level velocity, while maintaining cross-level consistency in bulk deformation across LOD results. As a result, it largely decouples finest-level enrichment quality from the number of LOD levels, addressing a practical limitation of VelPro at small timestep sizes where many levels are required to obtain sufficient enrichment. To make this volumetric setting practical for Progressive Dynamics, we add two supporting contributions. First, we construct volumetric hierarchies and introduce a simple and effective topology-aware boundary-binding method that enables reliable prolongation between overlapping, but not-necessarily-conforming, meshes using a barycentric-like linear interpolant. Second, instead of applying the subspace approach of Zhang et al. [2024] for reducing coarse model locking, we show that a lightweight, resolution-based stiffness rescaling via a simple Young's-modulus adjustment [Chen et al. 2017] is both effective and well-suited for progressive volumetric simulation. Together, these contributions jointly realize Volumetric Progressive Dynamics. We demonstrate its high-fidelity LOD matching for volumetric elastodynamics across 1D, 2D, and 3D scenarios with high speeds, large deformations, and frictional contact.