A PLINE point landing back on the first vertex (endpoint snap) now
closes the polyline instead of stacking a duplicate vertex there —
including an arc closing segment, whose bulge is already computed for
the last-to-first span (#421). Line mode requires two real segments
first so a doubled-back line isn't treated as closed. Setting
Closed: Yes in the properties panel on a polyline whose last vertex
already sits on the first drops the duplicate control point for the
same reason.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
A wide polyline with per-vertex varying widths rendered at its widest edge
(uniform-width ones were already exact). Draw the true taper instead.
`WireModel.taper_widths` carries a per-point full band width. The wire
instance (native slim + web fat) gains per-endpoint `world_hw_a/b`, and both
wire shaders interpolate `mix(hw_a, hw_b, which_end)` so each segment's band
narrows/widens linearly — depth-tested, and the linetype dash still applies.
Alignment (widths must match the tessellated points) is solved by building
both together: a new `TruckObject::TaperedLines(points, widths)`, filled by
`common::tapered_band_points` (straight = endpoints, arc = 16 samples with the
width lerped along it). to_truck routes a varying-width polyline here —
LwPolyline before the PLINEGEN split, Polyline2D at its return — while a
uniform-width one keeps the constant-band Contour path unchanged. `world_width`
stays the widest edge as the PDF-stroke + zoom-floor fallback.
Blocks fall back to the constant-widest band (`LocalWire` carries no
taper_widths).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Extends the wide-polyline shader band to the two cases the first pass left on
the hatch pipeline.
Polyline2D:
- A flat wide Polyline2D now draws its band from the centre-line wire
(`world_width`), same as LwPolyline (`polyline_band_width` handles both).
- A thickened wide Polyline2D extrudes a solid 3-D tube. `thick_wide_band`'s
body moves to a shared `common::thick_band_tube(origin, fills, thickness,
normal, to_wcs)`; LwPolyline delegates to it and Polyline2D calls it from
its thickness path. Tube edges read black for both kinds.
- The model-space wide-band hatch loop is deleted (both kinds now wire/tube).
Blocks:
- Block-internal wide polylines draw the shader band too. `LocalWire` carries
`world_width`; `emit_wire` scales it by the insert transform (average of the
X/Y axis image lengths) so the band tracks a scaled insert, and the scaled
width joins the batch `style_key`. `push_block_wide_fills` (the block hatch
band) is removed.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Entering a thickness (DXF 39 extrusion) on a wide polyline now works end
to end:
- The properties Thickness field is a General-group common prop, so it is
routed to apply_common_prop (set_entity_thickness) instead of the
geometry setter, which ignored it — the value was silently dropped and
reverted to 0.
- A wide polyline extrudes its whole band into a 3-D tube (outer + inner
walls with top and bottom caps), not just its centreline.
- The tube is real 3-D geometry, not a flat draw-order hatch: it renders
solid in every view mode with true depth, so nothing shows through the
walls. The flat 2-D band fill is skipped for a thickened polyline.
- A fill whose triangles span depth keeps its real depth (no draw-order
bias), so the extrusion's own edge wires stay in front of the surface
and remain visible instead of only the silhouette.
- The corner and cap edge lines read black, framing the coloured tube.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A wide polyline draws a solid band, but hit-testing only ever saw the
centreline 8 px out, so a donut could only be selected by clicking the
phantom circle inside the disc it paints. `self.hatches` — the map the
hatch pick channel walks — is filled from HATCH and SOLID alone, so the
band `wide_fills` produces was drawn (via `synced_hatch_models`) and never
picked.
The band rides in on `pick_tris`, the same channel a thickness wall uses:
`wide_fills` already computes it, so it costs one tessellation and inherits
the block transform. It ear clips rather than fans — an arc band is an
annular sector, concave on its inner edge — reusing `triangulate_planar`.
Wiring `pick_tris` through `Lines` alone was not enough: a plain wide
polyline leaves `to_truck` as `Contour`, and a PLINEGEN=0 one as
`SegmentedLines`. Both now carry it.
This needs the wire's cullable box to cover the band, and it did not.
`bounding_box()` boxes a polyline's stored vertices, knowing nothing of the
width painted around them: a donut's two vertices sit on one horizontal
line, so the box had zero height and rejected every click on the disc
before any triangle was tested. Every site that stamps the entity box onto
a wire now goes through `set_wire_aabb`, which widens it over `pick_tris`
(a no-op for the entities that have none, which is nearly all), and the
block cache chains `pick_tris` into its own box for the same reason.
That box was already too small for the centreline itself — an arc leaves
the vertex box — so a donut was unselectable at its top and bottom at
enough zoom. Widening fixes that too.
Verified end-to-end: tessellate a width-0.5 donut on a 0.05 centreline
radius, then `click_hit` five points 20 px clear of the centreline — all
land, and a click outside the disc still misses.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
DXF codes 43 / 40 / 41 store a polyline band's full width, and
`polyline_segment_fill` offsets ±hw about the centreline, so the stored
value has to be halved. Both `wide_fills` passed it in whole and drew
every wide polyline at double width.
The codebase was writing the spec value and reading it as something else:
`make_donut` stores `outer_r - inner_r`, a full width, which `wide_fills`
then treated as a half-width. So OCS mis-drew even its own donuts.
Seen on budweiser2018.dwg handle 2579, a donut of width 2.2 on a 1.1
centreline radius: it should fill out to radius 2.2 and instead reached
3.3 — a disc 1.5× its real size, overflowing the square it sits in.
Affects every wide polyline, so TRACE and PEDIT-widened runs come back to
true size too. The writers already stored full width and are left alone,
as is the property panel, which shows the file's own value.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Selection tested a flat 8 px radius around each wire's centreline and
nothing else, so two things the user can see were not pickable.
A wire renders as a band `line_weight_px` wide, so pick now widens to that
rendered half-width via `pick_tolerance_px`, mirroring the wire shader's
`select(0.5, half_width, lwdisplay_enable)`. Behaviour is unchanged for
every standard weight (the widest, 2.11 mm, renders 7.97 px half-width —
just under the 8 px threshold); this keeps the two sides from drifting
apart if the display boost in `lineweight_to_px` ever changes.
Entities extruded by a DXF thickness draw their wall as four edges with
nothing in between, so the interior was a hole the cursor fell through.
WireModel gains `pick_tris`: triangles hit-testing treats as solid and the
renderer never uploads. Kept apart from `fill_tris` because that channel
reaches the GPU, and a wall that rendered shaded would change how every
thickness drawing looks. Ranked below `fill_tris` — those are drawn, these
are not, so where they overlap the drawn face is what the user means.
Walls are dropped when a wire is projected into a floating viewport:
`points` are reprojected and clipped into paper coords there, so cloned
model-space triangles would hit-test at a model-scale offset. Extruded
entities stay selectable by their edges, which do get projected.
The wall loop runs on every hover that misses everything else, so it
rejects on the wire's AABB first — an extruded circle is ~128 triangles
and a drawing full of thickness would otherwise project every wall on
each mouse move.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The Current Vertex row is now a ◀ / ▶ stepper (new PropValue::Stepper)
showing "i / N". Stepping it moves the panel's focus through the
polyline's vertices — Vertex X/Y and the per-vertex start/end widths show
and edit the focused vertex instead of always the first — and the focused
vertex's grip is drawn hot (filled) in the drawing so it's visible while
navigating. Focus wraps around and resets to the first vertex when the
selection changes. Adds Area and Length to the LwPolyline Geometry group
(Polyline2D already had them). Applies to LwPolyline and Polyline2D.
The focused vertex is threaded to the per-entity property builder/editor
through a dispatch thread-local (like the curve-tolerance override), so
the PropertyEditable trait signatures are unchanged.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Draw the polyline width bands with the stored width offset to each side
of the centreline rather than half of it.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Reclassify every property row to match standard palette behaviour: a row
is editable only when its value maps directly to a stored field AND its
apply_geom_prop handler is wired; computed/derived/count/handle/
cross-object values stay read-only.
Newly editable (all apply-wired): attribute tag/prompt; ellipse major
radius; hatch Double; lwpolyline closed/linetype-gen; mline style;
multileader annotative/landing/background-fill; polyline 2D+3D vertex
coords/segment widths/linetype-gen; shape style; spline control/fit
point coords, weight, fit tolerance, tangents; table break-option flags;
text alignment point, upside-down, backward; underlay display flags.
Corrections: spline Degree -> read-only (editing desynced the knot
vector); removed a duplicate leader "Arrowhead" row.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The spec-conforming property builders dropped the rows that used these
helpers, leaving them unreferenced: hookline_dir_str (leader),
length_and_area (lwpolyline), render_mode_label / STD_VIEWS /
viewport_view_label (viewport). No behavior change.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Rewrite each entity's property builder to the per-entity group/row spec:
the correct sections (Geometry, Misc, Text, Pattern, Lines & Arrows, Leaders,
Block, …) with the spec's rows and real computed values — Diameter,
Circumference, Area, Delta X/Y/Z, Angle, Total angle, Arc length, Radius ratio,
etc. — plus apply routing for the editable rows.
Covers ~26 entities (Line, Circle, Arc, Point, Ellipse, Spline, polylines,
Ray/XLine, Insert, Text, MText, Hatch, Leader, MultiLeader, Tolerance, Solid,
Solid3D/Region/Body, meshes, MLine, Raster/Wipeout, Underlay, Table, Viewport,
Attribute, OLE). The 3D Visualization/Material group and the full Dimension
spec are deferred (they need document access for material/dimstyle name
resolution). Rows whose data is not in the pinned acadrust revision are shown
as empty placeholders, to be filled when the dependency is bumped.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Groundwork for making the Properties panel conform to the per-entity group/row
spec (PROPERTIES.md). The panel already renders a Vec of sections, but each
entity could only express a single geometry section.
Change PropertyEditable::geometry_properties (and the EntityTypeOps enum
dispatch) to return Vec<PropSection>, update the two impl macros, and flatten
in properties_sectioned so the panel shows [General] + the entity's groups.
Every entity builder is wrapped to return its existing section as a one-element
Vec — pure mechanical change, no rows or titles altered, panel output identical.
Enables Phase 2: rewriting each entity's groups/rows to match the spec.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The solid fill band of a wide LwPolyline / Polyline2D was built from
absolute WCS vertex coordinates cast straight to f32, then handed to a
HatchModel with world_origin = [0, 0]. At UTM-scale coordinates (~1e6)
f32 resolves to ~0.06, so the half-width offset collapsed and the
relative-to-eye fill shader cancelled `boundary - eye` to noise — the
band rendered as a string of squares. (Exploding the polyline drops the
width, hence no band and a clean line, which is why that "fixed" it.)
Build the band relative to a world_origin (the first vertex) in f64 and
store the small f32 offsets, mirroring how baked hatch fills keep
precision. Same class of bug as the on-create hatch-fill fix.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Line, Circle and Arc reported their lengths/quantities in the Geometry
section, but polylines (and rectangles, which are closed polylines) only
listed vertex count, closed flag and elevation. Add read-only Length and
Area rows: length is the true path length with arc segments measured by
their arc length, area treats the polyline as closed with a circular
segment correction per bulge.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Move the 30 flat modules under src/scene/ into six folders by role:
convert (entity→geometry), text (fonts/shaping), model (render models),
pick (hit-test/selection/grips/xclip), view (camera/transform/render),
cache (block + property caches). pipeline/ is unchanged.
Full path migration — all `scene::X` references become
`scene::<group>::X`, no compatibility re-exports. render.rs items that
were `pub(super)` (parent was scene) become `pub(in crate::scene)` to
keep their original scene-wide visibility.
No behavior change; build and tests are green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The MIRROR command's LwPolyline / Polyline2D closures reflected the
vertices but left the bulges untouched, so every curved segment of a
mirrored polyline bowed to the wrong side. A reflection reverses the
side a bulge arc bows to — negate it alongside the vertex reflection
(same convention acadrust applies on its reflecting-transform paths).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Grip markers drew visibly offset from the entity on large-coordinate
(UTM-scale) drawings: every Grippable impl cast the f64 entity coordinates
to f32 BEFORE the world-offset subtraction, and at 1e7 magnitude an f32
holds ~0.9 drawing units of rounding error. The wires subtract the offset
in f64 first (precision-preserving), so the grips landed up to ~1 unit
away from the geometry they belong to.
GripDef.world is now DVec3: producers fill it straight from the f64
entity data, refresh_selected_grips subtracts the world offset in f64,
and only the small offset-local result is cast to f32 for screen-space
projection (grips_to_screen / find_hit_grip) and drag state.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Phase 2 of the grip overhaul: when the cursor dwells on a selected
entity's grip the overlay opens a popup menu with entity-specific
options (Stretch / Add Vertex / Remove Vertex / Convert to
Arc-Line / …). Picking an item dispatches `apply_grip_menu`; the
default `Stretch` entry is a no-op that lets the user click the
grip to start the normal drag.
- `GripMenuItem` + `GripMenuAction` (full vocabulary covering
stretch, add/remove vertex, convert to arc/line, reverse arrows,
text-position variants, hatch parameters, tangent direction).
- `Grippable` trait gains `grip_menu` + `apply_grip_menu` with
trait-default `Stretch`-only impls so every existing entity gets
the popup for free.
- `EntityTypeOps` dispatches both methods across the same entity
list as the existing grip / property machinery.
- `OpenCADStudio` carries `grip_hover` (dwell tracker) +
`grip_popup` (open menu). `update_grip_hover` runs from
`ViewportMove`: hit-tests grips, refreshes the dwell timer, and
opens the popup after 600 ms. Cursor drift past 80 px or a grip
click dismisses it.
- `view.rs` paints the popup as an absolute-positioned column of
buttons at the grip's screen anchor; each button publishes
`Message::GripMenuPick(idx)`.
- `LwPolyline` overrides `Grippable` manually (skips the standard
macro) so its vertex grip exposes Add/Remove Vertex and its
segment-midpoint grip exposes Add Vertex + Convert to Arc/Line.
`apply_grip_menu` performs the edits: vertex insertion at the
chord midpoint inheriting the previous bulge, vertex removal,
and bulge toggle for the arc/line conversion.
Phase 1 of bringing the grip vocabulary in line with the standard
CAD convention: drop the per-position-type shape encoding (Diamond
for translate, Circle for parameter) and use a plain square for
every endpoint / vertex / centre grip. The behavioural midpoint vs
vertex distinction stays — it lives on `GripDef::is_midpoint` and
drives `Translate` vs `Absolute` in the grip-edit dispatcher — only
the marker shape collapses.
- `GripShape` keeps `Square`, `Rectangle`, `Triangle`. Diamond /
Circle are gone.
- `GripDef` gains `dir: Option<[f32; 2]>` — a world-XY direction
vector consumed by `Rectangle` to orient the box along its
segment.
- `entities::common` exposes `square_grip`, `center_grip` (same
square marker, flagged as translate), `rectangle_grip(id, world,
dir)` for oriented mid-segment handles, and a kept-for-Phase-2
`triangle_grip`.
- `overlay::GripMarker` / `grips_to_screen[_paper]` thread `dir`
through to the canvas painter; the Rectangle path rotates the
box around the grip centre using the world-XY direction (flipping
the sin for screen-Y).
Every existing `diamond_grip(id, w)` call becomes `center_grip(id,
w)` — the visual change is square-replacing-diamond at line
midpoints / arc midpoints / circle centres / ellipse centres /
viewport / hatch loop centroids / dimension grips / image corners /
multileader / ray / underlay / ole2frame / solid3d.
`LwPolyline` grows a stretch handle on every segment (straight or
arc), drawn as the new oriented rectangle. The grip-edit path
translates both segment endpoints for straight segments and
adjusts the arc bulge from the new midpoint for arc segments.
Every entity file ended with the same three-trait wrapper block:
impl Grippable for T {
fn grips(&self) -> Vec<GripDef> { grips(self) }
fn apply_grip(&mut self, ...) { apply_grip(self, ...) }
}
impl PropertyEditable for T { ... }
impl Transformable for T { ... }
— 23 lines of pure delegation around five same-named free functions.
Replace with `crate::impl_entity_basics!(T);` (a macro in
entities/traits.rs that expands to the three trait impls).
Applied where the file already follows the free-fn delegation
convention (Arc, Circle, Ellipse, Insert, Leader, Line, LwPolyline,
MultiLeader, Ole2Frame, Point, Spline, Viewport). Files that inlined
the trait method bodies directly (Ray, XLine, Shape, Solid, Tolerance,
MLine, Mesh, Solid3D/Region/Body, Table, RasterImage, Wipeout,
Underlay, Hatch, Polyline, Polyline2D, Polyline3D, Dimension) left
alone — they already skip the indirection. Text/MText/Attribute use
the with-text-style flavour and will move once that variant is needed
beyond the existing two manual impls.
A second macro `impl_entity_basics_with_text_styles!` is included for
the text-like flavour but no entity uses it yet.
Net: -204 lines.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
The same DXF/DWG bulge → (center, radius, sweep) formula was inlined
in six places (hatch outline, polyline tess + truck path, lwpolyline
×4, scene hatch fill, explode bulge_to_arc) — each with subtly
different sweep-direction handling for the bulge sign.
Add `entities::common::BulgeArc { center, radius, start_angle,
end_angle, sweep }` with one `from_bulge(p0, p1, bulge)` constructor
and a `sample(t)` helper. Callsites collapse to a few lines.
Net: -121 lines, one canonical sweep-direction convention shared by
all consumers.
array.rs (the path-along-curve f32 helper) keeps its inline math —
its sign convention is inverted relative to the others and changing
it without exercising the array-path command risks regressing the
output.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Two free helpers in app/commands.rs lived as big match-on-EntityType
blocks: massprop_entity (Circle/Arc/Line/LwPolyline/Ellipse area +
perimeter + centroid, ~140 lines) and entity_text_content /
replace_entity_text (Text/MText/AttributeDefinition/AttributeEntity).
Move each to its own trait in entities/traits.rs and implement
per-entity:
MassPropsCalc — Circle, Arc, Line, LwPolyline, Ellipse
TextContent — Text, MText, AttributeDefinition, AttributeEntity
EntityTypeOps gets dispatch shims that route to the trait via the
existing macro, so callsites just call entity.mass_props() /
entity.text_content() / entity.replace_text(search, rep).
The remaining free helpers in commands.rs (entity_list_details,
entity_extra_info, entity_type_name, build_data_extraction_csv) are
single-command formatting helpers tightly coupled to LIST / EXTRACT /
text-format output. Distributing them as per-entity methods would
inflate every entity file with command-side formatting concerns
without making the command-side any cleaner — left in place.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Five chunks moved out of the 5965-line scene/mod.rs to live with the
entities they belong to:
- wide_lwpolyline_fills → entities/lwpolyline.rs::wide_fills
- wide_polyline2d_fills → entities/polyline.rs::wide_fills
- polyline_segment_fill → entities/common.rs (shared by both above)
- text_obb_corners_native + text_baseline_points + text_greek_obb_tris
→ entities/text_support.rs (handles Text/MText/Attribute alike)
- append_insert_attribute_wires → entities/insert.rs
Net: scene/mod.rs 5965 → 5404 lines (~560 lines extracted). Three
helpers in scene/render.rs / scene/block_cache.rs widened from
pub(super) to pub(crate) so the relocated functions can still reach
them. scene::entity_aabb also widened for the same reason.
scene::tessellate_entity_dim_text stays put — it's a thin wrapper
around the private tessellate_entity dispatcher and moving it would
require exposing tessellate_entity's full signature across the crate.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Entity converters were casting WCS coordinates to f32 before the renderer
subtracted world_offset, which destroyed sub-unit precision on drawings
sitting at large coordinates (typical UTM-style CAD files). The multileader
case made it visible — glyphs warped under rotation — but every entity
that emits TruckObject::Lines/SegmentedLines/key_vertices/fill_tris was
affected.
Type changes (in src/scene/acad_to_truck.rs):
- TruckObject::Lines / SegmentedLines: Vec<[f32; 3]> → Vec<[f64; 3]>
- TruckEntity::key_vertices / fill_tris: f32 → f64
All ~17 producer files updated to keep WCS coordinates in f64 right up to
the TruckEntity boundary. The consumer in scene/tessellate.rs now performs
`(x - ox) as f32` (f64 subtract, then cast) for points, key_vertices, and
fill_tris — preserving precision near the camera origin even when the
drawing sits at million-unit coordinates.
catmull_rom_pts (multileader spline) is now f64; the scene path widens its
offset-relative f32 ctrl points to f64 around the call and narrows back at
the output.
Notes:
- Table layout still uses glam::Vec3 (f32) internally; widened to f64 only
at the TruckEntity boundary for type compatibility. Separate cleanup to
switch its internal math to f64 is tracked.
- snap_pts and tangent_geoms remain f32 — they are UI feedback (snap
candidates, tangent hints) and the precision is sufficient there.
PolyfaceMesh and PolygonMesh were wireframe-only. They now render with
the same flat-color solid fill as Face3D entities.
- Add fill_tris: Vec<[f32;3]> to TruckEntity and WireModel
- PolyfaceMesh: fan-triangulate each face into fill_tris
- PolygonMesh: triangulate each grid quad into fill_tris
- tessellate.rs Lines branch: apply world_offset to fill_tris
- Face3DGpu::from_wires: collect fill_tris from all wires in addition
to Face3D key_vertices quads
- upload_face3d: pass all_wires so fill_tris are batched into one draw call
LwPolyline PLINEGEN=0 (DXF default): emit SegmentedLines with NaN
separators between vertex-to-vertex segments; wire_gpu resets
arc-length to 0 after each NaN so linetype pattern restarts per vertex.
PLINEGEN=1: existing Contour path unchanged (continuous pattern).
WireModel gains plinegen field propagated through tessellate pipeline.
Solid3D/Region/Body: call SabReader::read() when parse_sat() returns
None due to binary SAB format (DWG files / newer AutoCAD exports).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Tessellates bottom + top paths with NaN-separated walls at each vertex.
Arc segments (bulge != 0) use 16-step parametric tessellation.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- fix: polyline arc center sign was inverted (- → +) causing arcs to render on the
wrong side in LwPolyline and Polyline2D
- fix: store glyph strokes in local space with f64 origin so world_offset subtraction
uses f64 precision; prevents blocky text at large UTM coordinates
- fix: Face3D fill darkened to 45% so edge wires are visually distinct from fill
- fix: wire batch vertex buffer chunked to 256 MB GPU limit (was panic on large files)
- fix: gpu_face3d_edges changed from Option<WireGpu> to Vec<WireGpu> to support chunks
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Partial ellipse arcs now populate key_vertices with both endpoints so
Endpoint snap works correctly. LWPolyline arc segments (bulge ≠ 0) get
a diamond grip at the arc midpoint; dragging it recomputes the segment
bulge via circumcircle of start/mid/end, giving interactive arc editing.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Empty LwPolyline and single-control-point Spline fallbacks were calling
builder::line(&v, &v) with the same Rc vertex, triggering the
truck-topology panic "Two same vertices cannot construct an edge."
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
