fill_triangles bounded the slab triangulator by edges x slabs, as if every
edge crossed every slab. A ring sampled finely at a close zoom has hundreds
of edges and slabs but only four edges in each slab, so the estimate ran a
hundred times over the hover highlight's budget and the fill was dropped,
leaving only the outline. Count the slabs each edge actually spans instead.
Region2::triangulate tested every edge against every slab, so its work was
the overestimate. It now sweeps upward with the edges crossing the current
slab, giving the same triangles in time proportional to them.
Fixes#164
Co-authored-by: Vitali M. <[email protected]>
* Add B-spline basis, knot insertion and NURBS surfaces to geom
Freeform faces need local refinement and gap-free joins between patches
with different knot vectors, which tensor B-spline grids cannot give;
T-splines can, and the first user is an N-sided Boundary Fill of
non-planar loops. This lays the univariate groundwork they rest on, in
the L0 geometry crate so it stays independent of the B-rep kernel:
- Cox-de Boor basis of one function from its local knot vector, on
half-open spans with a left-limit side for the domain end, with
derivatives (NURBS Book eq. 2.5, 2.9)
- knot insertion into a single basis function (Sederberg et al. 2004
section 3) and Bezier extraction of one function by repeated insertion
- Boehm knot insertion for curves (NURBS Book A5.1), de Casteljau
evaluation and sub-segments
- a rational tensor NURBS surface with evaluation, knot insertion and
clamping, and a rational Bezier patch type
All input is checked (finite, monotone knots, positive weights, size
caps) and returns SplineError; nothing indexes unchecked.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01J53sR6gEaVt56soFDpTck8
* Add T-spline surfaces: T-mesh, evaluation, AS check, refinement, extraction
Tensor B-spline faces refine only by whole rows and columns and cannot
join patches with different knot vectors without gaps. T-splines allow
T-junctions in the control net, which fixes both; the first user is an
N-sided Boundary Fill. This adds the maths only (no command, no change
in behaviour):
- T-mesh in index space with knot values per line, validated (outer
rectangle, rectangular faces, no empty lines, size caps); local knot
vectors read off rays from each vertex, rays leaving the mesh repeat
the boundary (Sederberg et al. 2003 section 3)
- rational T-spline evaluation and first derivatives for odd bi-degree,
with a complete (p-1)/2-line frame and the domain inside it
- T-junction extensions and the analysis-suitability check (Scott et al.
2012 section 2)
- local refinement that keeps the surface exactly: requested knot lines
are cut in, then every original blending function is carried as a
record and split (violation 1) or the mesh gains edges (violations 2
and 3) until each record is a blending function of the refined mesh
(Sederberg et al. 2004 section 3); analysis-suitable input stays
analysis-suitable by carrying conflicting T-junctions across faces
- NURBS <-> T-spline conversion for meshes without T-junctions, and
Bezier extraction over the rectangles no blending-function knot line
crosses
Measured: regular T-spline vs NURBS < 1e-12, round trip exact, partition
of unity with T-junctions < 1e-14, refinement deviation <= 1.4e-14 over
40 random refinements, Bezier patches vs surface < 1e-14.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01J53sR6gEaVt56soFDpTck8
* Convert T-splines to sewn NURBS sheet bodies in the kernel
A T-spline is only useful to the modeller once it is a B-rep face set.
tspline_sheet builds an open shell: a mesh without T-junctions becomes
one clamped NURBS face; otherwise each Bezier element is a face, and
sides are split at the T-points where neighbours' corners land, so all
faces share vertices and edges and the sheet is one oriented shell
(V - E + F = 1). Every truck call runs under guard. No command yet;
Boundary Fill will be the first caller.
Tests: one face for a regular surface, sewn Bezier faces with
T-junctions, tessellated points on the surface to ~1e-9 mm, and hostile
control nets (coincident, 1e300, needle-thin) never panic.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01J53sR6gEaVt56soFDpTck8
---------
Co-authored-by: Claude Opus 5.5 <[email protected]>
Extrude, revolve (partial and full turn), tapered extrude, loft (incl. to a
point), sweep, path sweep, coil, primitives, lip, emboss and thicken attach
the exact history of the bodies they build: each face's profile segment, cap
or operand face, and each edge's operand edge, recorded by topology identity
inside the building call. Nothing is sampled; a body whose faces do not follow
the expected construction carries no history. Face sources are unchanged.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01J53sR6gEaVt56soFDpTck8
Group kernel pieces across circular rims and hidden surface seams for hovering, selection, dialogs, and measurement. Preserve physical references and cover full-item toggling and picking with regression tests.
Fixes#88
The kernel moved from monstertruck to truck: truck's booleans handle blind
holes, pockets and bosses that monstertruck's did not (see the ADR). Fillets
and chamfers on straight convex edges between planar faces are our own exact
local B-rep operation. The document holds parameters with unit-aware
expressions and a timeline that re-evaluates incrementally.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
