terrain op• Data kinds: mesh → signal
• Call: import fullseye as fs; fs.ledger.mesh_edge_lengths(V, F, *, per: 'str' = 'vertex') -> 'np.ndarray' (to call the implementation directly, import render3d; render3d.mesh_edge_lengths(V, F, *, per: 'str' = 'vertex') -> 'np.ndarray'; from the registry, ops3d.get("mesh_edge_lengths"))
Local edge length of a triangle mesh → `(N,)` per vertex (mean of incident edges),
> The detailed description below is the original text — the summary and the headings are translated.
`(M,) per face (mean of its 3 edges) or (E,)` per unique edge.
This is the resolution map of the mesh in its own units: the shortest wavelength a
region can carry as *geometry* is about twice the local edge (Nyquist), which is what
:func:mesh_subdivide (`target_edge) and :func:displacement_band_weights` use.
Deterministic; fail-closed on degenerate meshes / unknown `per`.
無向の一意な辺 `(E,2)` を取り、各辺の長さ(メッシュ単位、float64)を集計する。
• `per='vertex': 頂点に接する辺長の平均 (N,)`。どの面にも属さない孤立頂点は
辺を持たないので、無言で 全辺の平均値 が入る(ゼロにはならない)。
• `per='face': 面の 3 辺の平均 (M,)`。
• `per='edge': 一意辺そのものの長さ (E,)。辺の並びは np.unique` の辞書順
(頂点 index の小さい順)で、`F` の順とは対応しない。
`per が上記 3 つ以外、頂点/面が空、face index 範囲外、非有限座標は ValueError`。
`displacement_band_weights の local_edge や mesh_subdivide` の
`target_edge` を決める(例: 中央値の半分)ために使う。
• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).
• Operator provenance and references — the sources of the research/methods this op family came from.
• itokawa_regolith_hero — py -3.11 examples_3d/itokawa_regolith_hero.py
signal as input)terrain)mesh_displace_fbm · terrain_region_mask · mesh_scatter_boulders · mesh_subdivide · displacement_band_weights · mesh_displace_spectrum · bump_normals_fbm
*Provenance: render3d.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.