capsule_sdf — 3D `sdf_csg` op

• Data kinds: coordgrid → sdf

• Call: import fullseye as fs; fs.ledger.capsule_sdf(grid, a, b, radius) (to call the implementation directly, import sdf_ops; sdf_ops.capsule_sdf(grid, a, b, radius); from the registry, ops3d.get("capsule_sdf"))

Usage

> This operator's description has not been translated yet. The original text follows as it is.

線分 `a–b を半径 radius` で太らせたカプセルの厳密な符号付き距離場。

`sdf(p) = ‖p - (a + clamp(((p-a)·(b-a))/‖b-a‖², 0, 1)·(b-a))‖ - radius`。

線分への最短距離そのものなので全空間で勾配ノルム 1(円柱と違い端が丸いぶん、

角が無く厳密)。リブ・配管・骨・ワイヤ・工具の掃引体積の近似に向く。

引数と検証(`ValueError`):

• `grid: 最終軸が 3 の float 配列 (..., 3)`。

• `a / b: 芯線の端点(要素数 3)。a == b なら球(sphere_sdf` と一致)。

• `radius`: 太さ(負は拒否)。

返り値: `grid.shape[:-1]` の float64。

使いどころ: 工具の到達性を「工具の掃引体積が部品と交わらないか」で見るとき、工具を

カプセルで置いて `sdf_intersect` の最小値が正かを見る。骨梁・血管・繊維の合成にも。

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)

• procedural_hand — py -3.11 examples_3d/procedural_hand.py

• sdf_csg — py -3.11 examples_3d/sdf_csg.py

Ops the type connects to (they accept `sdf` as input)

sdf_to_occupancy · fuse_to_voxel · integrate · extract_surface_points · query_distance · sdf_union · sdf_intersect · sdf_subtract

Same category (`sdf_csg`)

grid_coords · sphere_sdf · box_sdf · plane_sdf · cylinder_sdf · torus_sdf · sdf_union · sdf_intersect

*Provenance: sdf_ops.py — 3D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

capsule_sdf — 3D sdf_csg op