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We introduce vertex block descent, a block coordinate descent solution for the variational form of implicit Euler through vertex-level Gauss-Seidel iterations. It operates with local vertex position updates that achieve reductions in global variational energy with maximized parallelism. This forms a physics solver that can achieve numerical convergence with unconditional stability and exceptional computation performance. It can also fit in a given computation budget by simply limiting the iteration count while maintaining its stability and superior convergence rate. We present and evaluate our method in the context of elastic body dynamics, providing details of all essential components and showing that it outperforms alternative techniques. In addition, we discuss and show examples of how our method can be used for other simulation systems, including particle-based simulations and rigid bodies.
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This content will become publicly available on August 31, 2026
Two-Pass Shock Propagation for Stable Stacking with Gauss-Seidel
Rigid body simulators using the Gauss–Seidel method have been widely adopted for their simplicity, efficiency, and robustness. However, these methods struggle when simulating stable stacking with frictional contact because, unlike global methods, local methods, such as Gauss–Seidel, resolve constraints individually, leading to slow information propagation between bodies. To address this limitation, we introduce two-pass shock propagation, a technique that preserves the advantages of local methods while achieving stable and efficient simulation of frictional stacking without the need to rely on global approaches. The core idea behind two-pass shock propagation is that the upward pass leaves unused impulses on the bottom body, which can be stored and effectively applied during the downward pass. Through extensive experiments, we demonstrate that two-pass shock propagation significantly improves both performance and accuracy.
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- PAR ID:
- 10654716
- Publisher / Repository:
- ACM
- Date Published:
- Journal Name:
- Proceedings of the ACM on Computer Graphics and Interactive Techniques
- Volume:
- 8
- Issue:
- 4
- ISSN:
- 2577-6193
- Page Range / eLocation ID:
- 1 to 18
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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