curve op• Data kinds: points → points
• Call: import fullseye as fs; fs.ledger.fit_spline_curve(points, smooth=0.0, k=3, n=None) (to call the implementation directly, import curve3d; curve3d.fit_spline_curve(points, smooth=0.0, k=3, n=None); from the registry, ops3d.get("fit_spline_curve"))
Smooth and resample an ordered 3-D point sequence with a B-spline. → (M,3). For smoothing noisy trajectories and edges.
scipy.interpolate.splprep/splev. smooth=0 interpolates, >0 smooths. n = number of output points (default = number of inputs).
Fits a parametric B-spline with splprep([x, y, z], s=smooth, k=k) (parameter u∈[0,1], scipy's default chord-length parameterisation), evaluates it with splev at u = linspace(0, 1, n) and returns the (n,3) float64. Since u is equally spaced, the output points are not strictly equally spaced in arc length (if arc-length equal spacing is needed, pass the result through resample_uniform).
• smooth: scipy's smoothing condition s. Fits with the fewest knots such that the residual sum of squares is at most s. 0 means interpolation through all points; larger is smoother (unit is coordinate squared).
• k: spline degree (default 3). If the point count N is k or less, ValueError.
• n: number of output points. None means the input point count.
• The input is assumed to be (N,3) ordered by index; there is no shape validation other than the point count.
Used as a preprocessing stage that smooths noisy edge point sequences or trajectories before passing them to curvature_torsion / frenet_frame. To carry the tck around, use fit_bspline_curve / eval_bspline_curve.
• 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.
• bspline_freeform — py -3.11 examples_3d/bspline_freeform.py
points as input)points_to_voxel · gaussians_to_voxel · estimate_point_normals · to_points · match_points_ncc · match_pca · moment_axes · icp_point2point_3d
curve)curvature_torsion · frenet_frame · arc_length · resample_uniform
*Provenance: curve3d.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.