* feat(geom): surfaces through curve networks, and spline spaces to build them Adds spline_space (clamped B-spline spaces, Hermite interpolation, exact embedding by Bézier degree elevation and knot insertion, a monotone cubic for reparameterising) and network (loft, Coons and Gordon surfaces through curves in one or two directions, with G1/G2 cross-boundary conditions against a neighbouring face). Part of #763. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * feat(kernel): boundary surfaces from sketch curves, 3D curves and edges kernel::boundary_network turns sketch chains, 3D sketch polylines and edge chains into network curves, gives G1 frames of the faces along open edges (EdgeFaces), builds the B-spline face (sides split at chain vertices so a join shares the body's edges) and joins it into a surface body by stitching. G2 is refused for now (not supported yet). Part of #763. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> * fix(kernel): second derivatives of B-spline surfaces in the vendored truck-geometry BSplineSurface::uuder and vvder multiplied the second differences by p instead of p·(p − 1), as BSplineCurve::der2 does, so every surface of degree p ≥ 3 (NURBS too, through its homogeneous surface) reported 1/(p − 1) of its second derivative: a cubic surface's curvature read as half. This is why a G2 boundary surface on a cylinder measured half the curvature it carries (#763). New tests hold both to finite differences for degrees 2 to 5. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * feat(kernel): G2 boundary surfaces against a body's face The network always carried the face's curvature across a G2 edge; the refusal came from measuring it with truck's halved surface second derivatives (fixed in the previous commit). EdgeFaces now reads the face's second fundamental form from the exact second derivatives instead of differencing the normal. A new test holds the curvature across a cylinder's edge to the cylinder's within 0.1%, also with a sheared far curve; G3 is refused (a network holds up to G2). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * test(kernel): a boundary patch with straight corners measures its own area A stadium's arcs meet its lines at 180°, so the Coons patch is singular at its corners. From such a corner the reference mesher's boundary walk ran onto the B-spline's extrapolation past its domain (a planar spline passes through every point of its plane there), and the face measured 289 mm² for its 158.5 (#763). The vendored mesher's bounded projection (nearest_projection, #2043) keeps the walk on the domain; this holds it there, by the faces, the measuring mesh and the display mesh. The display path (#1653) was never affected. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * feat(geom,kernel): three-sided boundary surfaces (one side collapsed to a point) A network curve may be a PointCurve: the apex where the two sides beside it meet. The curves through it cross it at the point itself, its row of the net collapses there, and the kernel's face leaves that side out of its loop (three edges, one vertex at the apex). One point per patch, as a side; refused elsewhere, when it moves, or with a continuity condition. Tests: a triangle and a quarter disc filled flat with their analytic areas (40 mm², 25π), by geom and by the kernel's faces and meshes. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * feat(doc): boundary surfaces through curve networks and loops of three or four FeatureKind::SurfaceNetwork saves a network as `u` and `v` curves, each a sketch chain (planar or 3D), a chain of a body's edges with an optional G1/G2 continuity, or a point (the apex of a three-sided patch), and an `operation` that can join the surface into the body of its edges. A SurfaceBoundary of three or four sketch curves, refused until now, builds as the flat Coons patch of its loop (three collapse the side opposite the first curve). The format change is one pending file; feature-walk goldens record the new variant's sketches, bodies and points. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * feat(engine): surface.boundary through loops of three or four and curve networks The command keeps its loop form (two to four curves of one sketch; three and four now build the flat patch of the loop, crown refused there) and gains a network form: `u` and `v`, each curve a sketch curve id, a {sketch?, curves} chain (planar or 3D), a {body, edges, continuity?} edge chain (g1/g2 with the face beside it) or a {point} for a three-sided patch, with `operation` new or join. Edits may move between the two forms (timeline.redefine accepts the command now that it has a dialog). Tests: analytic areas of loop patches and of a hyperbolic paraboloid bounded by four 3D lines (every mesh vertex on z = xy/10), a loft across two sketches, G1 and G2 measured across a cylinder's edge with inspect.continuity (angle < 0.1°; curvature jump 1e-16 with G2 against 0.027 with G1), 26 hostile networks refused without panicking, and u/v added to hostile_params_never_panic. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * feat(ui): Boundary Surface dialog Curves and Cross curves take sketch curves and edges (picks that meet end to end in one sketch or body are one chain); Continuity and Operation (New Body or Join). Two to four sketch curves of one sketch with nothing across are the loop patch; anything else is a network. Edit Feature brings either back (per-side orders, crown and stations the dialog does not show are kept). Strings in en, ja and zh. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * docs: ROADMAP M8 and the bridge patch's notes for boundary networks (#763) Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * test(oracle): a boundary surface through a loop, thickened (#763) Case 83: four sketch curves (a square's three sides and a half circle for its top) make one boundary surface, thickened 2 mm; analytic values from tools/oracle-analytic/cases_surfaces.py (V = 2A, area 2A + 2P, centroid by moments). Recipes gain boundary_surface, thicken and remove. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM * refactor: boundary surfaces, review cleanups Project onto the face once per derivative evaluation (the frame is passed to natural() and reused by scale()), keep each track's finite-difference step instead of rescanning its table, export the kernel's edge-pick and chain caps and the default station count for the engine, doc and dialog to share, map TooLarge spline errors to KernelError::TooLarge, reuse the engine's operation parser, and skip the dialog's sketch lookup when the picks are no loop. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01LGeCa5jWWdroMWvXxN3LLM --------- Co-authored-by: jyviko <2501648+jyviko@users.noreply.github.com> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com> Co-authored-by: bherbruck <brennen.herbruck@gmail.com>
Reference tests (the oracle)
Each directory is one case:
recipe.json: the part, written in SolidCraft's recipe format (sketches in sketch-local coordinates, features with their parameters, faces and edges picked by a world-space point).cargo xtask oraclereplays it through SolidCraft's command engine.expected.json: what the part must measure, and where those numbers come from.reference.stl(optional): a fine triangulation of the expected part, used to check the shape itself (surface distance), not only its totals.
Run every case with cargo xtask oracle; it writes docs/oracle.md.
expected.json
{
"source": "analytic",
"method": "box 40 x 30 x 20: V = abc, A = 2(ab + bc + ca)",
"body_count": 1,
"volume_mm3": 24000.0,
"area_mm2": 5200.0,
"center_of_mass": [20.0, 15.0, 10.0],
"bbox": { "min": [0.0, 0.0, 0.0], "max": [40.0, 30.0, 20.0] },
"faces": 6
}
| Field | Meaning |
|---|---|
source |
"analytic" (closed-form geometry, worked out by hand; method gives the formulas) or "freecad <version>" (built from the same recipe by tools/freecad-oracle/). |
method |
How the numbers were obtained: formulas for analytic cases, the construction for FreeCAD ones. |
body_count |
Number of solid bodies. |
volume_mm3, area_mm2 |
Totals over all bodies. |
center_of_mass |
Volume-weighted centroid of all bodies (uniform density). |
bbox |
Axis-aligned bounding box of all bodies. |
faces |
Optional. Only where the geometry fixes the count: a face is a maximal smooth patch of one surface (a full cylinder side is one face; coplanar neighbours are one face). |
compare |
Optional. Restricts the comparison to these keys (for example ["volume_mm3", "area_mm2"] where kernels legitimately build different corner patches); note says why. |
tolerance |
Optional overrides: rel (volume, area; default 1e-3), abs_mm (centre of mass and bbox, default 1e-3 × the bbox diagonal), surface_mm (STL surface distance). |
note |
Optional remarks. |
No value here was measured in, or exported from, any commercial CAD product.