While state-of-the-art generative models produce high-fidelity 3D meshes, these outputs lack the physical properties required for interactive simulation, gaming, or robotics. We introduce Gen2Physics, a unified and automated framework that grounds generated meshes in physics by automatically decomposing them into their constituent material components. Unlike prior approaches, which focus on volumetric representations incompatible with standard physics engines, Gen2Physics operates directly on meshes to produce immediately simulation-ready assets. Our pipeline integrates a fine-tuned Vision Transformer for dense material segmentation, a robust 2D-to-3D consistency projection, and a Vision-Language Model (VLM) guided refinement that leverages contextual reasoning to assign physical properties and infer internal geometry (solid vs. hollow). By converting surface patches into volumes with distinct densities, our method enables physically plausible dynamic simulations. Experimental results on the ABO-500 and PartNet-Material benchmarks demonstrate that Gen2Physics more than doubles the material segmentation accuracy of prior physics-grounding pipelines (15.6 to 48.3 mIoU), while matching the mass-estimation accuracy of volumetric methods and being the only approach to output watertight per-material sub-meshes.
Figures & tables
Figure 2: Process of our 2D-to-3D consistency projection. A fine-tuned ViT predicts material segmentation masks, which are possibly noisy and not consistent across views. We project each face of our asset onto the rendered views, taking into account occlusions. For each face, we assign a label corresponding to the material with the highest frequency in the segmentation masks. The final material prediction is consistent across views. We then re-render the segmentation masks.
Figure 3: Samples of the PartNet-Material dataset. Dense segmentation masks are obtained by manually assigning material labels to each individual part of the asset.
Figure 4: We compare Gen2Physics (Ours), NeRF2Physics, and PUGS on a material identification task. The visualizations show that the 2D-to-3D consistency projection and VLM refinement proposed in Gen2Physics ensure more coherent and accurate material segmentations. In contrast, NeRF2Physics and PUGS produce fragmented masks due to their reliance on local CLIP embeddings
Method
Sim. Ready
ADE ( ↓ )
ALDE ( ↓ )
APE ( ↓ )
MnRE ( ↑ )
NeRF2Physics
×
12.725
0.736
1.040
0.564
PUGS
×
9.461
0.661
0.767
0.576
VoMP
×
8.433
0.631
0.887
0.576
Phys4DGen
×
9.961
0.664
0.825
0.566
Gen2Physics (Ours)
✓
8.447
0.651
1.170
0.600
Table 1: Mass estimation and asset usability on the ABO-500 benchmark. Gen2Physics obtains the best MnRE, and is within 0.2% of the best ADE, while being the only method to output watertight per-material sub-meshes (Sim. Ready) compatible with rigid-body physics engines. Baselines reported from [ 35 , 11 ] .
Method
Wood
Fabric
Metal
Plastic
Glass
Ceramic
Stone
mIoU [%] ↑
NeRF2Physics
61.87
2.67
23.23
1.03
6.12
0.00
21.43
14.54
PUGS
69.50
4.94
15.66
0.61
3.90
0.00
29.84
15.56
Gen2Physics (ViT only)
66.50
10.88
38.71
33.97
5.34
0.00
25.23
22.58
Gen2Physics (Full)
86.23
35.72
84.38
71.93
40.11
43.49
24.32
48.27
Table 2: Per-class Intersection-over-Union (IoU [%] ↑ ) and mean IoU (mIoU [%] ↑ ) on the PartNet-Material benchmark. The 8 reported categories are the foreground material classes populated across the test split. Organic and Leather never occur and are excluded, while Paper has 0.00 IoU for all methods and is omitted for space. Overall mIoU is calculated as the unweighted mean across these active classes. Colors denote the best and second-best results respectively.
Figure 5: Qualitative result showing part-reconstruction, material and physics assignment for a TRELLIS generated multi-composite asset. While both methods estimate plausible total mass, PUGS treats the mesh as a monolithic asset. In contrast, our framework decomposes and reconstructs watertight sub-meshes for a physically plausible dynamic behavior, as shown by the MuJoCo simulation [ 39 ] .
Method
ADE ( ↓ )
ALDE ( ↓ )
APE ( ↓ )
MnRE ( ↑ )
w/o Solid/Hollow
7.636
0.699
2.189
0.595
Full
8.447
0.651
1.170
0.600
Table 3: Ablation study on the ABO-500 mass estimation benchmark. Results show that internal structure reasoning is important for achieving robust mass calculation.
Synthesizing physics-grounded 3D assets is a critical bottleneck for interactive virtual worlds and embodied AI. Existing methods predominantly focus on static geometry, overlooking the functional properties essential for interaction. We propose that interactive asset generation must be rooted in functional logic and hierarchical physics. To bridge this gap, we introduce PhysForge, a decoupled two-stage framework supported by PhysDB, a large-scale dataset of 150,000 assets with four-tier physical annotations. First, a VLM acts as a "physical architect" to plan a "Hierarchical Physical Blueprint" defining material, functional, and kinematic constraints. Second, a physics-grounded diffusion model realizes this blueprint by synthesizing high-fidelity geometry alongside precise kinematic parameters via a novel KineVoxel Injection (KVI) mechanism. Experiments demonstrate that PhysForge produces functionally plausible, simulation-ready assets, providing a robust data engine for interactive 3D content and embodied agents.
Generating interactive 3D assets from a single image requires realistic appearance, fidelity to the depicted object, and plausible physical behavior. Yet detailed geometry alone does not determine how an object should move or deform. We introduce PhysAg3D, which couples 3D generative models with agentic reasoning and tool use. A vision-language agent first infers semantic parts, candidate interactions, and physical priors from the image; a 3D generator then produces a textured whole-object mesh from the same image. A hierarchical interaction representation links these revisable priors to mechanisms and the generated surfaces they control, organizing interaction construction and refinement. Guided by this representation and observations of the mesh, the agent uses geometric and physical tools to construct parts, joints, deformable regions, and surface bindings while retaining useful generated geometry and materials. Rendered interactions and execution measurements guide targeted revisions within a fixed budget. The framework accommodates both rigid articulation and compliant deformation. Quantitative and qualitative evaluations on real photographs and external benchmarks demonstrate detailed, image-aligned assets with plausible interactions. Ablations support bounded refinement and source-surface preservation. Project Page: supra-3d.github.io/PhysAg3D.
Bi'an Du, Fanpeng Meng, Jiemin Fang +5
Peking University · Guangdong Laboratory of Artificial Intelligence and Digital Economy (SZ) · Huawei +1
Significant advancements in 3D asset creation have enabled high-fidelity 3D generation from images. However, most existing representations remain inherently static, lacking the ability to model physically plausible behaviors under dynamic interactions. We present PhysCreator, a unified framework that directly generates simulation-ready 3D representations with spatially varying physical properties from images. Unlike prior approaches that treat physical attributes as simple post-hoc predictions or rely on expensive per-instance optimization, we reformulate physical property estimation within a unified 3D representation learning framework. We introduce a voxel-aligned latent space by lifting image observations into a spatially structured 3D representation, in which geometry, appearance, and physical properties are jointly modeled and inferred in a feed-forward manner. To enable scalable learning without densely annotated physical ground truth, we leverage vision-language distillation to transfer material-aware semantic priors from powerful vision-language models into spatially grounded voxel-level supervision. Experiments demonstrate that our method achieves superior visual quality, physical plausibility, and generalization compared to prior approaches.
Shiyan Zheng, Ming Li, Lei Han +1
Xi’an Jiaotong University · The Chinese University of Hong Kong, Shenzhen · Discover Robotics