CoACD: 基于碰撞感知凹性与树搜索的近似凸分解

python -m pip install coacd trimesh open3d numpy
python -m pip show coacd trimesh open3d

import argparse
import inspect
from pathlib import Path
from time import perf_counter

import coacd
import numpy as np
import open3d as o3d
import trimesh

parser = argparse.ArgumentParser()
parser.add_argument("mesh")
parser.add_argument("output")
parser.add_argument("--show", action="store_true")
args = parser.parse_args()

mesh = trimesh.load(args.mesh, force="mesh")
if not isinstance(mesh, trimesh.Trimesh) or mesh.is_empty:
    raise ValueError("需要非空三角网格")
if not np.isfinite(mesh.vertices).all() or mesh.faces.shape[1] != 3:
    raise ValueError("输入包含非有限坐标或非三角面")
print("bounds:", mesh.bounds, "watertight:", mesh.is_watertight)
print("run_coacd:", inspect.signature(coacd.run_coacd))

destination = Path(args.output)
destination.mkdir(parents=True, exist_ok=False)
start = perf_counter()
parts = coacd.run_coacd(
    coacd.Mesh(mesh.vertices, mesh.faces),
    threshold=0.05,
    seed=42,
)
if not parts:
    raise RuntimeError("分解没有返回组件")
print(f"parts={len(parts)}, seconds={perf_counter() - start:.3f}")

rng = np.random.default_rng(42)
visuals = []
for index, (vertices, faces) in enumerate(parts):
    part = trimesh.Trimesh(vertices=vertices, faces=faces, process=False)
    part.export(destination / f"part-{index:03d}.obj")
    if args.show:
        visual = o3d.geometry.TriangleMesh(
            o3d.utility.Vector3dVector(vertices),
            o3d.utility.Vector3iVector(faces),
        )
        visual.compute_vertex_normals()
        visual.paint_uniform_color(rng.uniform(0.25, 0.9, 3))
        visuals.append(visual)
if args.show:
    o3d.visualization.draw_geometries(visuals, window_name="CoACD parts")