tb_reflect_points — 2D typed op

Data kinds: pointspoints

Call: fullseye.apply(img, "tb_reflect_points", a=0.5, b=0.5) (the 2-D model is one image plus two scalar knobs a,b∈[0,1])

tb_reflect_points: input → output

*The figure is the actual output on a synthetic 128×128 input. Left: input, right: output. Point clouds are drawn as a top-down scatter (brightness = z), 1-D series as a line plot, volumes as the maximum-intensity projection along z, videos as the middle frame, complex images as magnitude; return values that are not pictures are shown as the values themselves.*

*Knob a does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

*Knob b does not change the output (measured: identical at 0.1 / 0.5 / 0.9).*

Stages (the ops that come before → this op, left to right):

tb_reflect_points: stages (docs site)

On other images (synthetic scene / photo / coins. Top row: inputs, bottom row: their outputs. Knobs at default):

tb_reflect_points: other inputs (docs site)

Usage

Mirror a point cloud across a plane (point plane_point, normal plane_normal). -> (N,3).

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

各点 p の平面からの符号付き距離 `d = (p - plane_point) · n`(n は正規化した法線)を取り、

`p' = p - 2 d n` を返す(Householder 鏡映)。平面上の点は動かず、平面の両側の点が入れ替わる。

点の並び順は保たれるので `p'[i]p[i]` の鏡像。座標の単位はそのまま。

• `points`: (N,3) の配列(float に変換)。形状検証はしない。

• `plane_point: 平面上の 1 点 (3,)。plane_normal`: 法線 (3,)(長さは任意、内部で正規化。

符号は結果に影響しない)。

注意: 法線はノルムに 1e-12 を足して割るため、ゼロベクトルを渡しても例外にならず点群がほぼ

そのまま返る(fail-closed ではない)。`reflection_symmetry_score` /

`detect_reflection_symmetry` の内部で使うほか、検出した対称面で欠損側を埋める(鏡像を元の

点群に連結する)形状補完にも使える。

2-D 進化レジストリへ橋渡しした 3d の op `reflect_points。実装は同じで、呼び出し規約だけ op(v, a, b) に合わせてある。この op に調整点は無く、ab` も使われない。

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.

Try it in Studio

The program below has been verified to run (same input as the figure). In Studio's help this block becomes buttons that load and run it on the spot.

img_to_points 0.50 0.50
tb_reflect_points 0.50 0.50

▸ Load this pipeline  ·  Load & run

Runnable examples (verified samples that actually call this op)

The examples below call the underlying ledger op reflect_points. This bridge op is the same implementation adapted to the fn(v, a, b) convention, so the behaviour carries over unchanged (only the call form differs).

reflection_symmetrypy -3.11 examples_3d/reflection_symmetry.py

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

identity · tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal

Same category (typed)

tb_points_to_voxel · tb_estimate_point_normals · tb_iss_keypoints · tb_project_points · tb_render_point_depth · tb_statistical_outlier_removal · tb_radius_outlier_removal · tb_voxel_grid_downsample


*Provenance: ops.py — 2D 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.