pc_lod_chain — 3D resolution op

Data kinds: pointstable

Call: import fullseye as fs; fs.ledger.pc_lod_chain(points, spacing, levels=3, seed=0) (to call the implementation directly, import meshres; meshres.pc_lod_chain(points, spacing, levels=3, seed=0); from the registry, ops3d.get("pc_lod_chain"))

Usage

Poisson-disk levels at doubling spacings (`table`).

> The detailed description below is the original text — the summary and the headings are translated.

Level 0 is the input; level *k* keeps no two points closer than

`spacing × 2^(k−1). Returns levels (list of clouds), spacings`,

`counts`.

手順: level 0 = 入力点群(検証後の float64 コピー)。level `k(1..levels`)は

直前の level に `pc_poisson_disk(prev, spacing * 2**(k-1), seed=seed + k - 1)`

を掛けたもの(累積的に間引くので、粗い level の点は必ず細かい level にも含まれる

= 入れ子)。点は動かさない(格子平均のような重心移動はしない)。

引数: `points (N, 3)(有限、MAX_POINTS 以下)、spacing > 0`(level 1

の最小点間距離、座標と同じ単位)、`levels は 1..16 の整数、seed` は

Poisson-disk の訪問順の乱数種(固定なら決定的)。

返り値(dict): `levels(levels + 1 個の (n_k, 3)` 配列のリスト)、

`spacings([0.0, spacing, 2*spacing, ...]、level 0 は 0)、counts`

(各 level の点数)、`n_levels(levels + 1`)。

検証(`ValueError): 点群の形・非有限・点数超過 / spacing` が非正 /

`levels` が整数でない・範囲外。

注意: 各 level の点数は `~ 面積 / spacing_k^2` の目安で 4 分の 1 ずつ減るが、

疎な領域(元の点間隔が `spacing_k` より大きい)は間引かれず残る。何を落としたかは

`pc_thinning_report(points, levels[k])` で数える。メッシュの LOD は

`mesh_lod_chain`。

Background guides (the physics and conventions behind this op)

depth_sensors — 深度センサの知識 — 測距原理・実機の値・欠測の出方

References (sample data, literature)

• 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.

Runnable examples (verified samples that actually call this op)

mesh_resolution_demopy -3.11 examples_3d/mesh_resolution_demo.py

Ops the type connects to (they accept table as input)

fuse_to_voxel · mesh_select_lod

Same category (resolution)

mesh_edge_stats · mesh_detail_map · mesh_split_long_edges · mesh_isotropic_remesh · mesh_sample_points · mesh_lod_chain · mesh_select_lod · mesh_reduction_report


*Provenance: meshres.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.