| """2026-10-07：交付版局部补洞、Taubin平滑及几何变化保护，无需GT。""" |
| import numpy as np |
| import trimesh |
| from scipy import ndimage |
| from skimage.measure import marching_cubes |
| from mesh_repair import repair_small_holes |
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|
|
|
| def topology(mesh): |
| counts = np.bincount(mesh.edges_unique_inverse) |
| bodies = int(mesh.body_count) |
| return {'boundary_edges': int((counts == 1).sum()), |
| 'components': bodies, 'watertight': bool(mesh.is_watertight), |
| 'handles': int(round((2*bodies-mesh.euler_number)/2)) if mesh.is_watertight else None} |
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|
|
| def scene_for(mesh): |
| import open3d as o3d |
| scene = o3d.t.geometry.RaycastingScene(nthreads=2) |
| scene.add_triangles(o3d.t.geometry.TriangleMesh( |
| o3d.core.Tensor(np.asarray(mesh.vertices, np.float32)), |
| o3d.core.Tensor(np.asarray(mesh.faces, np.int32)))) |
| return scene |
|
|
|
|
| def geometry_change(raw, result, seed): |
| import open3d as o3d |
| distances = [] |
| for target, source in [(raw, result), (result, raw)]: |
| points = trimesh.sample.sample_surface(source, 100000, seed=seed)[0] |
| distances.append(scene_for(target).compute_distance( |
| o3d.core.Tensor(np.asarray(points, np.float32)), nthreads=2).numpy()) |
| distances = np.concatenate(distances) |
| return {'extent_change_max': float(np.max(np.abs(result.extents / np.maximum(raw.extents, 1e-12)-1))), |
| 'surface_shift_p95': float(np.quantile(distances, .95)), |
| 'surface_shift_mean': float(distances.mean())} |
|
|
|
|
| def within_limits(change): |
| return change['extent_change_max'] <= .02 and change['surface_shift_p95'] <= .005 |
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|
|
| def close_small_tunnels(mesh): |
| import open3d as o3d |
| pitch, pad = 1/384, 4 |
| voxels = mesh.voxelized(pitch=pitch) |
| occupied = np.pad(voxels.matrix, pad) |
| origin = voxels.transform[:3, 3] - pad*pitch |
| x, y, z = np.meshgrid(*([np.arange(-2, 3)]*3), indexing='ij') |
| ball = x*x+y*y+z*z <= 4 |
| expanded = ndimage.binary_dilation(occupied, structure=ball) |
| closed = ndimage.binary_erosion(ndimage.binary_fill_holes(expanded), structure=ball) |
| closed |= occupied |
| field = ndimage.gaussian_filter(closed.astype(np.float32), sigma=.55) |
| vertices, faces, _, _ = marching_cubes(field, .5, spacing=(pitch,)*3, allow_degenerate=False) |
| result = trimesh.Trimesh(vertices+origin, faces, process=False) |
| result.fix_normals(multibody=True) |
| nearest = scene_for(mesh).compute_closest_points( |
| o3d.core.Tensor(np.asarray(result.vertices, np.float32)), nthreads=2) |
| target = nearest['points'].numpy() |
| ids = nearest['primitive_ids'].numpy().astype(np.int64) |
| selected = ((np.linalg.norm(target-result.vertices, axis=1) < 2*pitch) & |
| (np.einsum('ij,ij->i', result.vertex_normals, mesh.face_normals[ids]) > .5)) |
| projected = np.asarray(result.vertices).copy() |
| projected[selected] = .9*target[selected]+.1*projected[selected] |
| result.vertices = projected |
| return trimesh.smoothing.filter_taubin(result, lamb=.5, nu=.53, iterations=80) |
|
|
|
|
| def postprocess(mesh, seed=1234): |
| if not len(mesh.faces) or not np.isfinite(mesh.vertices).all(): |
| raise ValueError('Invalid input crown mesh') |
| seed = int(seed) % (2**32) |
| before = topology(mesh) |
| raw, boundary_meta = repair_small_holes(mesh, max_boundary_edges=32) |
| repaired = False |
| rejected = None |
| if raw.is_watertight and (topology(raw)['handles'] or 0) > 0: |
| try: |
| candidate = close_small_tunnels(raw) |
| change = geometry_change(mesh, candidate, seed) |
| after = topology(candidate) |
| repaired = bool(after['watertight'] and after['components'] <= before['components'] and |
| (after['handles'] or 0) < (topology(raw)['handles'] or 0) and within_limits(change)) |
| if not repaired: |
| rejected = {'topology': after, **change, 'reason': 'topology or geometry gate'} |
| except Exception as exc: |
| rejected = {'reason': repr(exc)} |
| result = candidate if repaired else trimesh.smoothing.filter_taubin(raw.copy(), lamb=.5, nu=.53, iterations=80) |
| change = geometry_change(mesh, result, seed) |
| passes = 80 |
| |
| if not within_limits(change): |
| repaired = False |
| result = trimesh.smoothing.filter_taubin(mesh.copy(), lamb=.5, nu=.53, iterations=20) |
| passes = 20 |
| change = geometry_change(mesh, result, seed) |
| if not within_limits(change): |
| result, passes = mesh.copy(), 0 |
| change = geometry_change(mesh, result, seed) |
| after = topology(result) |
| if after['boundary_edges']: |
| status = 'open_boundaries_remaining' |
| elif after['handles']: |
| status = 'major_topology_hole' |
| elif repaired or before['boundary_edges'] > after['boundary_edges']: |
| status = 'repaired' |
| else: |
| status = 'clean' |
| return result, {'status': status, 'topology_before': before, 'topology_after': after, |
| 'hole_repair_accepted': repaired, 'boundary_repair': boundary_meta, 'rejected_candidate': rejected, |
| 'taubin': {'lambda': .5, 'nu': .53, 'passes': passes}, 'pitch': 1/384, |
| 'closing_radius_voxels': 2, 'gaussian_sigma_voxels': .55, **change} |
|
|
