Gaussian Swaying: Surface-Based Framework for Aerodynamic Simulation with 3D Gaussians

TL;DR

Gaussian Swaying introduces a surface-based aerodynamic framework that uses 3D Gaussian surface patches to unify simulation and rendering without meshing. It derives per-patch aerodynamic forces and lightweight shading from the same surface representation, enabled by a training regime that enforces surface fidelity. The method achieves state-of-the-art efficiency and visual fidelity on synthetic and real-world wind-driven scenes, including a dedicated flag benchmark, and ablations validate the necessity of surface-aware modeling and the proposed losses. This approach offers a scalable, real-time capable solution for realistic aero-dynamic visualization in vision and graphics.

Abstract

Branches swaying in the breeze, flags rippling in the wind, and boats rocking on the water all show how aerodynamics shape natural motion -- an effect crucial for realism in vision and graphics. In this paper, we present Gaussian Swaying, a surface-based framework for aerodynamic simulation using 3D Gaussians. Unlike mesh-based methods that require costly meshing, or particle-based approaches that rely on discrete positional data, Gaussian Swaying models surfaces continuously with 3D Gaussians, enabling efficient and fine-grained aerodynamic interaction. Our framework unifies simulation and rendering on the same representation: Gaussian patches, which support force computation for dynamics while simultaneously providing normals for lightweight shading. Comprehensive experiments on both synthetic and real-world datasets across multiple metrics demonstrate that Gaussian Swaying achieves state-of-the-art performance and efficiency, offering a scalable approach for realistic aerodynamic scene simulation.

Figures (11)

• Figure 1: Gaussian Swaying is a unified surface-based framework that couples aerodynamic simulation with lightweight shading for efficient and realistic dynamics.
• Figure 2: Pipeline Overview. Gaussian Swaying is a unified surface-based framework for aerodynamics. By representing 3D Gaussians as continuous surface patches, it integrates aerodynamic simulation and realistic rendering within the same representation. Gaussian patches support aerodynamic force computation while also providing normals for lightweight shading, enabling realistic and efficient visual effects. Multi-view renderings of simulation results are shown on the right.
• Figure 3: Surface Formulation. Gaussian Swaying represents objects as Gaussian surface patches, each defined by a normal and effective area, enabling efficient surface-specific interactions. Left: a deforming flag modeled as Gaussian patches. Right: coupling with the MPM grid, where patches provide surface attributes and receive deformation updates. Blue line indicates the ground-truth surface, and shaded cells mark active simulation regions.
• Figure 4: Illustration of Aerodynamics and Lightweight Shading.(a) Incident flow (gray) and resulting aerodynamic forces on a Gaussian patch, with coordinate axes shown in red, green, and blue. (b) Principle of lightweight shading: the full BSDF formulation is approximated by an efficient local shading model. (c) Flag simulation results: (1) aerodynamics only, and (2) aerodynamics with lightweight shading.
• Figure 5: Qualitative Results of Aerodynamics. Gaussian Swaying generates realistic physics-based motion using 3D Gaussians across diverse materials.