Carries snaporca 0231bd5b68. Parity holds: 17 files identical, 8 diverging as expected.
A reflection reverses orientation, so mirror_entities now hands the reflected half back reversed
in ORDER and flipped per ENTITY — an arc swapping its angles as well as its ends, a spline
reversing its control points. Appending it to the source then yields one walkable chain instead
of two halves meeting head-to-head, and a mirrored CCW loop stays CCW.
This is the producer half of the confusion that cost three defects; the consumers (offset, and
the exact loop area) keep their defensive handling, because that is what makes them correct for
hand-built and imported sketches rather than only for geometry this function produced.
Contract change, carried with the reason: a mirrored line's p0 is the reflection of the SOURCE's
p1, and a mirrored CCW arc keeps a POSITIVE sweep — the reflection negates it, walking it the
other way negates it again. Both [SketchEdit] cases updated, and a new [SketchProfile] case
"a mirrored half continues the original chain" pins the property directly.
Kernel here: all tests passed, 2687 assertions in 232 test cases. GUI target builds and links.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Carries snaporca 572f794c84, d0f9a0052a, 9f7e4e3627 and 3974f8a170. Parity holds: 17 files
identical, 8 diverging by their expected counts.
EXACT AREA. A loop's area is now integrated entity by entity in traversal order — Green's
theorem — instead of being shoelaced over the render polyline, which faceted every arc into 24
chords and lost 2.02 mm2 on a 3706.86 mm2 stadium. 0.054%, invisible on screen, and wrong in a
number reported as "the area".
OFFSET FOLLOWS THE TRAVERSAL. Offsetting a mirrored profile put one half on the wrong side and
split the loop in two, because the chainer only followed p1->p0 links and each entity's offset
side was taken from its stored direction. Chains are now orientation-aware, seeded at a free end,
offset by `reversed ? -d : d`, and normalised head-to-tail on the way out — so offset is correct
for any input ordering and its own output cannot reintroduce the problem.
Both are the same underlying lesson, which has now cost three separate defects: an entity's
STORED direction is not its direction of TRAVEL around the loop.
THE LADDER. scripts/sketch-ladder.py is a graded suite of 2D sketches judged the way a person
judges them — VERTEX, LENGTH, ARC, TANGENT, SYMMETRY, CLOSED — with area only as a cross-check,
because area is derived and nobody can confirm it by eye. Eight rungs from a rectangle up to
MPD5 from the StudyCadCam corpus, a dia 27 x 95 pin reproduced as its revolve half-profile with
the R5 fillet tangency solved exactly. Entirely 2D: no extrude or any solid feature.
Kernel here: all tests passed, 2681 assertions in 231 test cases, including the new
"profile: a mirrored half offsets as one loop, not two". GUI target builds and links.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Carries snaporca 971320e129, 6b049f0dc6, 4aae782029, 444d59f212, 74cf3d7e54 and the build
guards from 597557a6e4. Parity re-verified after every hunk: 17 files identical, 8 diverging by
their expected counts — DesignPanel.cpp still 32, DesignCanvas.cpp still 16, which is the proof
each hunk landed on the right side rather than being copied over a real divergence.
OFFSET OFFSETS THE CHAIN. Per-entity offsetting returned a closed rectangle as four parallel
segments that no longer touch, so entities_to_wires gave four OPEN wires and nothing could be
extruded. offset_entities now chains by shared endpoints and repairs each seam by mitering the
neighbours to their intersection. Second bug, invisible to any single-entity test: +d meant
"left of travel" for a line but "radius + d" for an arc regardless of sweep, so a slot outline
offset with its straights going one way and its caps the other. The convention is now written on
the declaration and pinned by a test.
tests/libslic3r/test_sketchprofile.cpp is new and asserts the LOOP rather than coordinates —
the property that decides whether a profile can be built, and the one the existing single-entity
[SketchEdit] cases cannot see. Its include is catch2/catch_all.hpp here: this fork ships Catch2
v3 while snaporca is on v2, which is why the test files are a tolerated divergence.
RIGHT-CLICK PICKS WHAT YOU POINTED AT, so a line's own verbs are offered instead of the
empty-selection vocabulary; sk_delete stops sharing btn:delete with the feature tree; and an
element's defining number (length / radius / diameter / angle / distance) can be typed, from the
menu or from V.
TWELVE MCP SKETCH VERBS. The socket had ~40 verbs and none touched a sketch, so the 2D layer
could only be exercised by driving a GUI with synthetic clicks. sketch_describe reports each
closed loop, the loops it encloses as voids, exact areas, and where a chain is still open;
sketch_validate/sketch_heal are FreeCAD's ValidateSketch — find vertices that overlap within a
tolerance but carry no coincidence, then weld them AND record the constraint, so a loop closed
by floating-point luck becomes one closed by construction. scripts/mcp-sketch-smoke.py is the
loop that asserts all of it.
Kernel suite on this fork: all tests passed, 2677 assertions in 230 test cases. The GUI target
links against the rebuilt deps image (the wxInspector blockage is gone) and the binary carries
the new verbs.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
