Commit Graph

30 Commits

Author SHA1 Message Date
Levi Neuwirth beb61fca2f P13-I3: delete the hand-written notehead anchors; teach the extractor
BRAVURA_METRICS' NOTEHEAD_ANCHORS were hand-derived where every neighbouring
number in the table is machine-extracted from the SHA-pinned font -- the same
mistake as inferring band ownership downstream instead of reading it from the
source that had it. And they were wrong under any reading: they named
stemUpNW/stemDownSE, the corners a normal notehead's stems do not attach to and a
pair Bravura's noteheadBlack does not define, with an x of 1180 that reads as 1.18
staff spaces written in thousandths rather than the table's 1/1024 units (1.18 sp
= 1208). Nothing consumed them.

Deleted rather than corrected. The font is not vendored, so the true values cannot
be verified in-tree, and shipping data we cannot stand behind into a hash every
conformance claim declares is worse than shipping none. Verified empirically
before deciding, not reasoned about: changing the anchors breaks nothing in-tree
-- 30/30 targets, zero golden churn, no pinned literal hash -- so
GlyphCatalogIdentity moves once, now, while no claim declares the old one.

extract_bravura_outlines.py gains --anchors, emitting them from the pinned
bravura_metadata.json (anchors live in the SMuFL metadata, not the glyf bounds,
which is why the outline extraction never covered them). SMuFL anchors are points,
so they round to nearest -- unlike a bbox, which rounds outward so the metric box
contains the ink. The metadata's SHA-256 is deliberately left UNPINNED and
verify() now refuses an unpinned source, printing the digest to paste: the script
cannot regenerate anchors until an operator with the font pins it in a reviewable
commit, which is the discipline the other two sources already have.

The test guarding the anchors proved nothing. anchors_participate_in_the_hash
compared noteheadBlack (anchored) against noteheadWhole (not) and asserted they
hash differently -- but their advance and bbox differ too, so it would have passed
with the anchors ignored entirely. It now varies the anchors while holding every
other field fixed (presence, one coordinate, one name), against synthetic metrics
through a factored-out metrics_hash_of.

Pass-13 Batch 2 CLOSED. All three candidates resolved; two grew when examined.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 14:53:47 -04:00
Levi Neuwirth 24b6a34db9 Slurs: side from the stems, endpoints on the notes, apex clear of both
The rendered slurs were wrong in three independent ways, all visible in the
two-staff and three-staff goldens.

  1. Side. SlurDirection::Auto always arced above. The single-voice rule is
     OPPOSITE the stems -- all stems up puts the slur under the noteheads, all
     down puts it over them, and a mixed-stem span (which has no notehead side)
     goes above. Every Auto slur over a stem-up passage was drawn through its own
     stems. This is why stem direction had to land first: with every stem pointing
     up, "opposite the stems" means nothing.

  2. Endpoints. They sat at staff_top + gap -- a constant offset from the STAFF,
     not from the notes -- so a slur between two C6s hung below its own noteheads
     and crossed their ledger lines. They now sit a gap outside the endpoint
     column's ink, at the notehead's centre. Where the stem points the same way as
     the slur, that ink includes the stem, so the endpoint clears the stem tip.

  3. Clearance. The apex was span-proportional and blind, so a note between the
     endpoints poked straight through the arc. ColumnInk -- per staff, per column:
     top, bottom, stem direction, notehead centre -- is the obstacle field. The
     control points sit on the chord at thirds, so x is exactly linear in t and
     the arc's departure from the chord is 3*lift*t*(1-t); a column at t needing d
     more clearance forces an apex of at least d/(4*t*(1-t)).

An authored height is a floor, not a ceiling: clearance may raise it, so obeying
an author cannot draw a slur through a note. An authored direction still wins.

Obstacles are measured at the notehead CENTRE, the same x the endpoints use. The
first cut used the raw column x, which skews t and silently over-lifts: the
two-staff slur cleared its C6 by 4.05 spaces where 3.5 was needed. The clearance
test now asserts an upper bound as well as a lower one.

SLUR_INSET is gone. Endpoints at the notehead centres are what its 0.6-space
"tuck" approximated for the start point -- and got wrong for the end, where it
tucked a full notehead width to the LEFT of the final note.

Four mutations verified: always-above, staff-relative endpoints, no clearance
pass, and obstacles at the column x. The staff-relative-endpoint mutation PASSED
at first -- the tests asserted only "above the staff" / "below the staff", which a
staff-relative endpoint satisfies by construction. The exact-endpoint assertion
exists because that mutation survived.

Projection change, so no version moves; goldens churn.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 13:58:56 -04:00
Levi Neuwirth 7aa0b938e2 Stems point away from the middle line, and reach it
Every stem in the engine pointed up, on the notehead's right, at a constant
octave. A C6 three ledger lines above the staff grew an upward stem shooting past
everything -- visible in the two_staff and three_staff renders. It is also why the
slurs are wrong: an Auto slur is placed OPPOSITE the stems, so no correct side
could be chosen while every stem pointed the same way. Stems are therefore a
prerequisite for the slur fix, not merely adjacent to it.

  - Direction: away from the middle line, decided by the head furthest from it,
    ties going down (the convention for a note on the line, and for a chord that
    straddles it evenly).
  - Attachment: the side it points -- an up-stem at the lowest head's right edge,
    a down-stem at the highest head's left. Read from the head's own bounding box
    rather than the rounded NOTEHEAD_STEM_X: for noteheadBlack those are 1.1807
    and 0, and 1.1807 is Bravura's real stemUpSE (1.18). The old 1.15 was a
    rounding -- it accounts for the whole of ten_measure's churn, where every stem
    moved right by 0.031 and nothing else moved at all.
  - Length: an octave from the outer head, but drawn out to the middle line when
    the note lies beyond it, so no stem dangles in the ledger field.

No version moves. This is the PROJECTION changing, not a solver: to_constrained
emits different geometry from the same graph, so ENGRAVER_VERSION's promise (same
input => same output) is untouched. Every golden churns, stub and engrave alike,
because stems are constrained-stage geometry.

Locked by a_stem_points_away_from_the_middle_line_and_reaches_it, which re-pitches
a generated score across four octaves -- the corpus generator writes only low
notes, so nothing in the suite had ever exercised a down-stem. Mutation-verified:
restoring always-up plus fixed-octave fails it.

Parked, found on the way: BRAVURA_METRICS' notehead anchors are unusable as
written. They name stemUpNW/stemDownSE -- the corners an up- and down-stem never
attach to -- and their x of 1180 reads like 1.18 staff spaces written in
thousandths rather than the table's 1/1024 units (1.18 sp = 1208). Nothing
consumes them except metrics_hash, so correcting them would move the
GlyphCatalogIdentity every conformance claim declares. That makes three parked
candidates; the house rule opens a batch pass at three.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 13:47:47 -04:00
Levi Neuwirth 86635e43e1 Two-sided inter-staff renegotiation, and the cascade defect it uncovered
ENGRAVER_VERSION 11 -> 12. The inter-staff solve now closes a slack pair as well
as opening a crowded one, realizing the InterStaffGap band's declared height
exactly. SYSTEM_STAFF_PITCH is demoted from a floor to an initial arrangement the
solve fully renegotiates. This is what vertical_density_penalty was reporting: an
un-pressured multi-staff system sat at 0.739, honest sprawl against the declared
gap, because the axis is symmetric and the solve only ever expanded.

The band's height had no agreed meaning, so pin it: it is an INK CLEARANCE -- the
separation between the two staves' outermost content, exactly the unit
req:qmc:vertical measures. preferred 2.0 -> 5.0, min 1.0 -> 2.0. The old 2.0 was
a placeholder reconciled with nothing: neither the 8.0 staff-box gap the fixed
pitch of 12 produces, nor the ~6.4 ink clearance it leaves for plain content.
Realizing it would have crushed a relaxed system to a pitch of ~7.6. At 5.0 plain
ledgered content settles near a pitch of 10.6.

Making the solve two-sided immediately exposed a CASCADE DEFECT latent since v11.
The recurrence subtracted the upper staff's shift from the measured gap and then
added it back through the accumulator, so every pair below the first was
over-separated by exactly the shift above it. Both staves move; the relation is
shift_lower = shift_upper + target - (upper_lo - lower_hi), the UNSHIFTED gap.
three_staff_close_content's lower pair realized 21.06 against a declared 4.0. It
was invisible on two-staff fixtures (shift_upper = 0) and invisible to
inter_staff_shifts_cascade_down_three_staves, which asserted only s2 > s1 -- true
under both the correct and the double-counting recurrence.

What caught it was the metric measuring realized clearance back from the BAKED
output instead of the solve's own extents. Reading back solver intent would have
reported 0 and shipped the over-separation again. That design choice was made one
commit earlier for exactly this reason; the catalog rationale now recommends it to
any conforming implementation.

Once the solve realizes each declared clearance exactly, every inter-staff unit is
0 on a healthy solve -- the axis becomes a solver self-check, and its MEAN can no
longer distinguish "measured every realization" from "measured one". So
vertical_raw is split into vertical_units and the regressions assert the unit SET.
Four mutations verified: the double-counting recurrence, expand-only, the
glyph-members band filter, and first-system-only measurement each fail a named test.

No normative change, no version move: QMC formula, units, anchors, thresholds all
untouched; only its non-normative rationale is refreshed. Churn is the two
multi-staff engrave goldens: two_staff grew by exactly 3.0 (the target change, no
cascade); three_staff SHRANK by 9.06 -- the same +3 per pair, less the 17.06 of
over-separation the defect was adding. Single-staff and every stub golden are
byte-stable.

The 5.0 was the user's call. 4.0 ("one staff height") was chosen first and
withdrawn once its true consequence -- pitch 9.57, not the 11.04 an arithmetic slip
of mine had projected -- was measured rather than inferred. The slip: deriving
plain-content ink clearance from an aggregate metric by assuming two contributing
units when it had three.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 13:32:37 -04:00
Levi Neuwirth efaebb9acd Let the band model carry staff attribution instead of inferring it
Stroke and Curve gain `vertical_band: VerticalBandId`, the field GlyphObject has
always carried. Curve's own doc comment used to call it "a *free* primitive (no
vertical band, no spring slot)" -- but the projection computed each primitive's
band, used it for the glyphs, and threw it away for the strokes and curves.

The engraver then reconstructed it geometrically, and got it wrong twice: nearest
glyph by x handed a lower-staff stem to the upper staff (4132a7a), and nearest
glyph to a slur's start endpoint handed a bottom-staff slur to the top staff
(b1bfe04). Both tore primitives off their own notes, both reached a committed
golden, both were caught by review rather than by the gate. A slur is the proof
the inference can never be made safe: its endpoints are deliberately lifted clear
of its own staff, into the zone where the nearest notehead belongs to the
neighbour. No distance metric recovers the owner.

Both fixes were correct and both were the wrong shape -- reconstructing by
inference a fact the projection had in hand and discarded. So: the projection
declares it (a slur's staff is its notes' staff), the engraver's attribution
becomes three map lookups, and ~60 lines of geometric rules, epsilons, and
fallbacks are deleted.

Two bands had to become unconditional, since strokes could otherwise name bands
that no glyph had caused to exist -- validation now rejects that as UnknownBand:

  - a staff band per staff of the region, in the region's own staff order (the
    order y_origin stacks by), not only for staves that emitted a glyph. A staff
    whose clef is unbundled engraves to an anchor *stroke* and no glyph.
  - the margin band unconditionally, because a region's own traced anchor is a
    stroke that names it whether or not a margin glyph puts a member in it.

Both may carry zero members, as an inter-staff gap band already did: membership
realizes the spring solve over glyphs; existence is what attribution needs.
Strokes and curves are deliberately NOT added to VerticalBand::members -- their
band reference is one-way.

vertical_band is not part of ResolvedLayoutIR::canonical_bytes (primitives are
encoded field-by-field), so this is layout metadata outside the canonical
encoding: no companion-version bump, and ENGRAVER_VERSION stays at 11 because the
output is unchanged. Zero goldens churn -- which is the evidence that the declared
owner agrees with the inferred one across the entire corpus.

Locked by every_stroke_and_curve_names_a_band_that_exists, verified by mutation:
making the margin band conditional again fails it on valid_score_rich. The two
tear-off regressions are kept -- they now assert an outcome the data model
guarantees, which is where a dropped declaration would surface.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 10:37:27 -04:00
Levi Neuwirth f7350362a3 Close the inter-staff residual risk: a three-staff cascade fixture
The reviewer signed off on the inter-staff slice with one named residual risk:
the 3+-staff cumulative shift cascade was documented and traced correct but had
no fixture behind it -- valid_score_rich's "three staves" are three separate
single-staff regions, so each lands in its own system and the cascade never runs.

three_staff_close_content puts three staves in ONE region with deliberately
asymmetric pressure: the upper pair collides hard (C1 against C7), the lower pair
only gently. That asymmetry is what makes the fixture discriminating. Sizing each
pair independently -- the plausible wrong implementation -- measures the lower
pair against the middle staff's ORIGINAL position, hands the bottom staff only
its own small correction, and drags it back up through the middle staff.

Verified by mutation, not by assertion alone: with the cascade removed the bottom
staff's shift collapses from 34.68 to 4.56 against the middle staff's 15.06, and
both the shift ordering and the staff-line-gap assertions fail. two_staff_close_content
still passes under that same mutation, which is precisely why the new fixture was
needed.

Writing the test also corrected a wrong mental model, now recorded in DECISIONS.md:
a shift INCREMENT generally exceeds the lower pair's own raw correction, because
the upper staff's descent has itself eaten into that pair's gap and must be undone.
The first version of the test asserted the opposite and failed against a correct
solve.

The fixture additionally pins curve attribution against a three-band choice -- the
slur must still find the bottom staff, not merely the nearer of two -- and carries
its own render golden. No existing golden churns.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 10:20:35 -04:00
Levi Neuwirth b1bfe04d6c Inter-staff review fix: attribute a curve by its arc, not its nearest glyph
The stem tear-off repaired in 4132a7a had a twin one layer deeper, live in
the same fixture and baked into the same golden: the bottom staff's slur was
attributed to the TOP staff, kept shift 0, and tore off its own notes.

A distance metric cannot fix this one. A slur's start endpoint is deliberately
lifted off its notes -- staff_top + gap above, staff_bottom - gap below -- into
the inter-staff zone, where the nearest glyph is routinely a note on the
adjacent staff (here, a top-staff ledger note). So attribute a curve the way it
is drawn: the arc's direction picks the side. An upward arc (p1.y >= p0.y) hangs
below a staff -- take the greatest staff-line band bottom at or above p0.y; a
downward arc sits above one -- take the smallest band top at or below p0.y.
Fall back to the nearest band mid-line for a curve inside a staff.

Locked by a_slur_travels_with_its_own_staff, verified to fail without the fix
(d_bottom=8.695 > d_top=7.235 -- the slur riding the wrong staff).

Also assert the two metrics the solve moves rather than leaving them untested:
collision_penalty is 0 (the staves separate cleanly) and vertical_density_penalty
saturates at 1.0 -- the solve targets content extents while the metric scores the
realized gap against the band model's preferred height. That is the same
metric-vs-solver tension as casting_off under justification; DECISIONS.md records
it, plus three further reviewed gaps: staff-less content takes shift 0, the
preferred gap is read from the constructor rather than the region's declared
band, and the 3+-staff cumulative cascade is correct but unexercised.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 10:05:14 -04:00
Levi Neuwirth 4132a7ac05 Inter-staff review fix: make staff attribution y-aware (stems tore off)
Self-review of the inter-staff solve found a real bug: stroke->staff attribution
reused component_glyph, whose fallback picks the nearest glyph by X ALONE. That
is correct for a SLOT — both staves of a system share their x columns, hence
their spring slots, so the horizontal delta is the same either way — but wrong
for a STAFF: it handed a lower-staff stem to the UPPER staff's notehead. The
stem then kept the wrong vertical shift and tore off its own head (measured
worst stem->notehead distance 5.837 on the two-staff fixture vs 1.150, the stem
x-inset, on the single-staff one), and it polluted the upper staff's content
extent, inflating the computed gap.

Fix: the staff attribution uses a 2-D nearest for that fallback (a ledger still
resolves via owning_glyph's shared Pitch source; a staff line via its Staff
source). component_glyph is unchanged and still serves the horizontal path.

Also corrected: staff-attributed primitives now contribute their y ONLY through
the shifted path (Extent::add_x for x, add_y for the shifted staff extent), so a
lower staff's UNSHIFTED content can no longer inflate a system's max_y. Dead
Extent::add removed.

The corrected attribution yields a smaller, more accurate separation (two-staff
view_box height 36.1 -> 31.1). Regression multi_staff_stems_stay_on_their_own_
staff (verified to fail at 5.837 without the fix). Only the two-staff engrave
golden churned; single-staff goldens byte-stable. 948 tests, clippy 0, docs
-D warnings, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 09:42:51 -04:00
Levi Neuwirth 3978225e06 Inter-staff slice 2/2: renegotiate the gaps between a system's staves
The last vertical-spring piece: the gaps BETWEEN a system's staves are
renegotiated so tightly ledgered or slurred adjacent staves — which the
constrained stage stacks at a fixed pitch — separate. ENGRAVER_VERSION 10 -> 11
(a multi-staff score whose staves press together shifts them apart; a
single-staff score, with no inter-staff pair, is byte-identical).

Attribution (vertical_band + owning-glyph, per the chosen approach): a glyph via
its vertical_band (VerticalBandKind::Staff -> StaffId); a stem/ledger via its
notehead (component_glyph); a staff line via its Staff source; a slur via the
notehead nearest its start. Spacing is horizontal-only, so a primitive's y is
unchanged from the source frame the attribution reads.

The solve: per system, per staff, collect the real content y-extent (glyphs,
strokes, curves — ledgers and slurs included); order staves top-to-bottom by
their staff-line reference y (order fixed); shift each staff down by the
cumulative amount needed to bring its gap to the one above up to the band
model's preferred inter-staff gap. staff_shift[(system, staff)] is a per-staff
dy the bake applies (Placement::sunk) atop the per-system dy, so glyphs,
strokes, curves, the staff/measure/system records, content bounds, hit-test, and
quality metrics all read the same shifted geometry. The shifts grow each
system's extent, which the vertical stacking and justification then consume.

Regression inter_staff_solve_separates_colliding_staves (the two-staff fixture's
staff-line gap opens past the fixed pitch; a single-staff score keeps one staff
per system) + the two_staff_close_content render golden updates (slice 1 tight,
slice 2 separated). Only that engrave golden churned; single-staff goldens
byte-stable. 947 tests, clippy 0, docs -D warnings, conformance 8/8.

This completes the Standard-tier layout story end to end.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 23:04:25 -04:00
Levi Neuwirth f103641013 Inter-staff slice 1/2: a two-staff pressure fixture
Groundwork for inter-staff band-height renegotiation (the last vertical-spring
piece): a fixture whose two staves' content nearly collides at the engraver's
fixed staff pitch, so the pending solve has something meaningful to separate.

two_staff_close_content: a one-measure, two-staff (treble/treble) metric score.
The top staff descends into low ledger notes (down to C2); the bottom staff
climbs into high ledger notes (up to C6) under a slur that arcs further above
them. In the constrained frame the top staff's content occupies y ≈ [-8, +4]
and the bottom staff's ≈ [-12, -5], overlapping in [-8, -5] — the C2 ledgers
collide with the C6 + slur. Invariant-clean; 8 notes, 1 slur, 41 strokes
(the heavy ledgering), 1 curve.

Registered in the render-svg acceptance suite; its goldens (this commit) show
the CURRENT overlapping layout — slice 2 (the solve) will update the engrave
golden to show the staves separated. Invariant test added. 946 tests, clippy 0,
docs -D warnings, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 22:48:39 -04:00
Levi Neuwirth c818992835 Push 3 Standard-tier: optimal break search (replace greedy first-fit)
Casting-off's greedy first-fit + tail-only widow rebalance is replaced by a
deterministic badness-minimizing break search (optimal_breaks, a Knuth-Plass-
style dynamic program over the measure boundaries). ENGRAVER_VERSION 9 -> 10.

Objective: minimize the sum over ALL systems of the squared normalized underfill
((width_limit - w)/width_limit)^2. Squaring evens the systems; including the
FINAL system in the sum subsumes the old widow rebalance (the optimizer won't
leave a narrow final stub if a balanced partition is cheaper). It is the
additive, DP-tractable analog of the retired distribution_cost (max of the
catalog's break penalty and width-CV imbalance). On the ten-measure fixture the
search settles on 5/4 measures where greedy left a fuller-then-shorter split,
filling the final system more and pulling casting_off_quality down (~0.80 ->
~0.61) — the payoff, visible now that horizontal justification drives
system_break to ~0 so casting_off mostly sees the last system's fullness.

Break requirements (hard/soft/page) bound the DP's segments — a system may not
span a forced break — and walk_region still honours them and records skipped
content-less soft breaks as IrOverride, unchanged; optimal_breaks reports only
the automatic breaks. A system may exceed the width only as a single
unsplittable measure. Minimal still makes no optimality claim.

Deterministic: minimizes lexicographic (cost, system_count). Tests:
optimal_breaks_{balances_systems_and_avoids_a_final_widow, never_spans_a_forced_
break, is_deterministic_and_empty_when_unbounded}; the widow test now checks the
balanced measure distribution; wrapping-fixture metrics updated (casting_off
improved). Removed rebalance_widows/rebalance_region/distribution_cost + their
tests. Goldens regenerated (balanced systems; view_box stable — justification
still fills to width). 944 tests, clippy 0, docs -D warnings, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 21:29:08 -04:00
Levi Neuwirth fea446a182 Justification review fix: keep stems attached to their noteheads
An adversarial review of the justification commit found a SEVERE bug: stems
detach from their noteheads (~0.75 ss, up to ~1.5) in every justified system.
Root cause: the code used is_rigid_width_stroke to select slot-anchored strokes
on the false premise it covered stems. It is LEDGER-ONLY. A stem is an
Event-sourced stroke drawn at notehead_x + 1.15 with no same-source glyph
(noteheads are Pitch-sourced) and no baseline in its x-span, so it fell to the
affine branch and its intra-slot offset was scaled by the justification factor a,
floating it off its head into the gap. The spacing pass shared the same
classification (a smaller latent drift).

Fix: component_glyph classifies a stroke — a Staff (staff line) or
RepeatStructure (volta bracket, whose ending-number glyphs share its source)
source SPANS (affine); else owning_glyph (a ledger over its notehead, same Pitch
source); else the glyph with the greatest baseline <= the stroke's x — a stem's
own in-column notehead (stem_offset 1.15 < column step 1.6, so exactly its slot).
Applied in BOTH the spacing remap and casting, so stems ride their heads through
the whole pipeline. Ledgers are unchanged (owning_glyph path).

Regression: stem_offsets_from_the_notehead_survive_justification (verified to
fail without the fix). Goldens regenerated (stems now on their heads). The minor
slur-inset drift (same root cause, ~0.3 ss on a soft connector) is deferred with
a note. Folded into ENGRAVER_VERSION 8 (unreleased). 941 tests, clippy 0, docs
-D warnings, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 19:54:18 -04:00
Levi Neuwirth 7c038721d7 Push 3 Standard-tier: per-system justification (fill the content width)
Every non-final system of a multi-system region now stretches its horizontal
slack so its ink fills the content width, instead of sitting at its natural
left-aligned width. ENGRAVER_VERSION 7 → 8 (any wrapping score's baked geometry
differs; a single-system score is unchanged — its only system is ragged-right).

Casting bakes each system by a Placement: a vertical dy plus a horizontal affine
world_x = a·x + b (rigid = a:1, b:dx). A justified system spreads the slack
linearly (a = 1 + extra/span). The map is CLAMPED to the slot-source range: affine
within it, rigid slope-1 beyond it (bearing overhangs, staff lines drawn to the
ink edge), so the mapped ink extremes agree exactly with the per-slot deltas and
the ink spans exactly [left_margin, left_margin + content_width] (no over/under-
shoot). Slot-relative like the E1 remap: glyphs translate by the map at their
SLOT's source (intra-slot offsets survive), spanning strokes map endpoints through
the affine (they stretch), rigid-width strokes (stems/ledgers, via owning_glyph)
track their slot, slur control points map through the affine.

Not justified: a region's last system (ragged-right by convention), a degenerate
span, or a system already at/over width (never compressed into overlap).

Quality consequences (honest): system_break_penalty collapses to ~0 (the point);
the width-uniformity axes rise as the full non-final system contrasts with the
ragged last line (ten-measure casting_off ~0.45 → ~0.80) — a metric-semantics
follow-up noted in DECISIONS. Tests retargeted: the widow rebalance now shows in
measure distribution not baked widths; the floor-column test moved to a synthetic
vector (robust to fixture values). Goldens regenerated (view_box widens to the
content width; same 147 primitives, no collisions). 939 tests, clippy 0, docs
-D warnings, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 19:21:46 -04:00
Levi Neuwirth c5173d275e Push 3 (slur quality) 1/3: render dashed/dotted slurs faithfully
E2 drew every slur solid and surfaced a SlurLineStyleNotRendered diagnostic for
a non-Solid authored line. That deferral is now lifted: the Curve primitive
gains a `line: LineStyle` (from the slur's SpanStyle.line), threaded through the
resolved canonical encode (a per-curve style byte), the engrave remap, and
casting; render-svg emits stroke-dasharray (dashed = "0.5 0.35"; dotted =
round-capped "0 0.28"). The diagnostic variant is removed — the style is
rendered, not deferred, so `req:layoutir:slur-curve`'s "never silently rendered
solid" is satisfied by faithful rendering rather than a surfaced gap.

ENGRAVER_VERSION 5→6 (a dashed/dotted slur's resolved bytes and SVG differ).
Zero churn beyond the one dashed slur: the slur fixture's two solid curves are
byte-identical; only the editorial slur's <path> gained the dasharray. Solid
slurs and slur-free scores are unchanged. 932 tests, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 17:13:32 -04:00
Levi Neuwirth 81b7f42f0a Schema major 2 Phase E2: slur curves + cubic-bézier primitive
The third pipeline primitive kind, review-hardened (5 verified findings fixed
pre-commit). A `Curve` (four control points, mirroring `Stroke`) threads
through all three IR stages, the canonical-encode fingerprint (a 5th u32 count
prefix; width-lock 4→5), the round-trip provenance chains and count identity,
`to_render`, the stub solver, engrave remap + casting, SVG path emission, and
hit-testing.

Slurs draw as one cubic bézier per slur carrying the slur's exact provenance
(no synthesis). LayoutContent::Slur resolves each endpoint event to a Note
column at to_logical (SlurEndpoint At/Unresolved — E1's honest-placement
discipline); a symmetric arc whose apex sits `height` from the endpoint line;
curvature_override direction+height honored, style.line (dashed) deferred to
Push 3. Honest non-drawing (traced anchor kept) for an unresolved endpoint, a
non-left-to-right span, or a cross-staff slur (no single staff — would float
at yo=0). Authored height/thickness sanitized to defaults when non-positive
(a negative thickness would else fail validation and blank the layout).

Hit-test: HitShape::Curve (Copy) flattens the cubic to a 16-segment capsule
inside contains/intersects (one region per curve); a slur click resolves to
Slur generically (no editor arm; edit ops refuse it). render-svg: stroked
unfilled <path C> after strokes/before glyphs + curve_count + content-hull
bounds. engrave: HorizontalRemap::curves; casting curve_system = Rigid-to-
start-system (no de Casteljau split — deferred; break-spanning slur draws
whole in its start system, kept for the source surjection); ENGRAVER_VERSION
4→5; slur_shape_penalty now 0.0 by construction (Minimal draws the ideal arc).

Existing SVG goldens changed only in the provenance-note comment (curves now
enumerated) — geometry byte-identical; 6 snapshots gained curve_count; new
ten_measure_with_slurs goldens. 929 tests, conformance 8/8.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-08 15:33:00 -04:00
Levi Neuwirth 6651ae5fce E1 follow-up: slot-relative glyph remap (same-slot spacing preserved)
The spacing pass reserves a slot's full content extent in its advance, but
HorizontalRemap::glyphs moved every glyph independently by piecewise
interpolation — a same-slot companion whose absolute x crossed the next
slot's source was dragged by the wrong interval. E1 made it reachable: a
time signature after a morphed repeatLeft sits TIME_SIG_X + the sign's
right extension (~1.8sp) right of its barline, past the 1.6sp constrained
column step, collapsing the digits into the following note through the
real Engraver.

spacing::space_slots now returns each glyph-bearing slot's (source, target)
beside the interpolation control points; glyphs translate by their own
slot's rigid delta (intra-slot offsets survive verbatim), spanning strokes
keep endpoint interpolation, and rigid ledger strokes use the owning
glyph's slot delta exactly. Folded into ENGRAVER_VERSION 4 (unreleased this
push); scores without same-slot companions are byte-identical — only the
repeat fixture's engrave golden moved (volta digits).

Regression: time_signature_digits_ride_their_barline_slot_past_a_repeat_sign
(unbounded page so x-disjointness compares one line; verified to fail
against the interpolated remap).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-07 22:16:54 -04:00
Levi Neuwirth 7a9bf42119 Schema major 2 Phase E1: repeat barlines + volta brackets render
The first repeat-structure ink, review-hardened (19 verified findings fixed
pre-commit). Zero golden churn for repeat-free scores; four new goldens for
the ten_measure_with_repeats fixture.

layout-ir: repeats project LayoutContent::Repeat resolved at to_logical
(RepeatPlacement::At/RegionEnd/Unresolved — honest, no origin fallback;
zero-offsets judged by value; bare wall-clock boundaries draw no ink); deps
now from anchor_sites(). Constrained: coinciding measure barlines morph into
precomposed repeatLeft/Right/RightLeft (name-only, exact provenance kept);
standalone signs synthesize under a semantic (site, staff) instance key;
end repeats at the region close draw repeatDots beside a final barline (or
the full sign on continuing staves); start marks there draw nothing;
end-facing signs reserve their left reach via column overhang; time
signatures clear morphed signs; volta brackets = 3 strokes above the top
staff + timeSig digit numerals, kind-independent.

engrave: ENGRAVER_VERSION 3 -> 4; casting classifies barline columns via
is_barline_glyph AND direct Measure source, so standalone signs are never
phantom break candidates or measure records; criterion-6 round-trip covers
the repeat fixture.

render-svg: repeatLeft/Right/RightLeft/Dots outlines + metrics + font subset
regenerated from the SHA-pinned Bravura (fontTools 4.63.0); GlyphClass::Repeat.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-07 21:51:11 -04:00
Levi Neuwirth bc9fb27d36 Clear P12-I11: casting-off widow-rebalance evens the stub last system
RS-1 honestly failed the Minimal casting_off_quality threshold under the
reference engraver: greedy first-fit left a two-measure stub last system
(width CV 0.6145 -> clamped 1.0 > 0.90). Cleared the honest way — an
engrave-side balance pass, no Quality Metric Catalog or core-spec change.

Casting-off gains a second phase, a widow rebalance
(casting::rebalance_widows, run between the greedy walk and vertical
stacking): it moves whole trailing measures from a region's penultimate
system into its final one, choosing the shift that minimizes the larger of
the two distribution penalties the catalog defines for the break family —
the width imbalance (casting_off_quality, the CV of the region's system
widths) and the non-final break penalty (system_break_penalty, the mean of
|W-w|/W over non-final systems). distribution_cost computes each raw by the
same formula as quality.rs's casting_off_raw / system_break_raw (mean not
worst, abs not clamp), so the rebalance optimizes the values the metric
census will report. The two axes pull against each other, so their min-max
lands on a 6/4 split for RS-1 (casting_off 1.0 -> 0.4463, system_break
0.254 -> 0.677, every axis <= 0.90) — with comfortable margin, over the
fragile full-balance 5/5 (system_break 0.889, a hair under 0.90).

Scope is tight: only a region's last boundary moves, and only when greedy
placed it (an Automatic boundary with no break requirement or page force
pinned to its slot); a user/IR-anchored or page-forced boundary is never
disturbed, the penultimate system keeps >= 1 measure, the final never grows
past its predecessor, and the system count is unchanged — so every
break-count and page-assignment invariant (and all break-constraint tests)
hold untouched.

The casting_off 0.5 anchor and the 0.90 Minimal column were vindicated, not
relaxed: the engraver improved, no anchor rescale / threshold loosening /
RS-1 override. Core spec Chapter 9's "Minimal makes no optimality claim"
already permits the heuristic, so nothing normative changed (no .tex/PDF
rebuild). P12-I12 (the Standard-tier spacing floor on short scores) stays
open.

- engrave: rebalance_widows + distribution_cost + two-phase module docs;
  ENGRAVER_VERSION 2 -> 3 (a wrapping score's baked geometry differs from
  pure greedy); three new casting tests (even-split preference, the
  mean-not-worst break penalty for 3+ systems, and the resolved final
  system); the_wrapping_fixture_is_measured_honestly re-pinned to the 6/4
  values (both axes floor-warn under Standard, status untouched).
- testkit: RS-1 minimal_xfail row removed (promoted to a plain Pass); the
  suite ships no xfail rows.
- render-svg: ten_measure.engrave.{svg,snapshot} goldens regenerated
  (view_box width 83.99 -> 64.95; still two systems).
- process trail: PASS12_BATCH I11 struck; PASS12_RATIFICATION_LOG
  "no spec change" section; engrave DECISIONS casting-off decision 9 +
  quality item 7 + candidate promoted.

860 workspace tests pass; clippy -D warnings, fmt --check, rustdoc
-D warnings all clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
2026-07-03 19:09:51 -04:00
Levi Neuwirth 0316160395 Phase 3 tranche 1: casting-off, K1 schema-fill, value-restoring undo
The chosen Phase-3 attack, run as two parallel waves. 829 workspace
tests pass; clippy -D warnings, fmt, and rustdoc clean; all three
spec documents build with zero undefined references.

Casting-off (epiphany-engrave/src/casting.rs, wired into the
Engraver):
- Greedy first-fit system breaking per region at measure-start
  barline columns; a measure that would overflow the content width
  starts a new system. Hard SystemBreakAt/PageBreakAt always
  honoured; soft breaks honoured unless pathological (skipped with
  the spec's warning + IrOverride-recorded decision).
- Vertical stacking from real content extents with the inter-system
  gap read from the vertical band model; page overflow starts the
  next page. World frame: pages stacked vertically, coordinates
  baked into glyphs/strokes, so the SVG renderer, hit-testing, and
  the GUI viewport are unchanged.
- Real ResolvedPage/ResolvedSystem trees (1-based page numbers,
  content bounding boxes, staves from staff-line segments, measures
  from barline columns); every chosen break appends an
  EngravingDecision with MUSCLOID EngravedBreak provenance,
  UserOverride-attributed via the new ConstrainedLayoutIR
  break_origins sidecar; staff lines split per system with
  synthesized continuation provenance.
- Break-constraint evaluation flips: satisfied iff the layout breaks
  at the slot. The two single-system tests invert deliberately
  (a hard break is now honoured; a user break is honoured and
  attributed instead of warned). Geometric constraints evaluate in
  the pre-casting spaced frame (documented).
- Page geometry is engraver-side PageGeometry (A4 portrait at an
  8 mm staff: page 105 x 148.5 staff spaces, margins 7.5, content
  90 x 133.5; arithmetic documented) — Canvas.layout_defaults has no
  graph home and is a schema-major addition (P12-I7).
  ENGRAVER_VERSION = 2. Goldens regenerated: ten_measure_single_staff
  engraves as 2 systems (viewBox 84x20.6, was 103x11);
  valid_score_rich as 3 systems; stub goldens byte-identical.

K1 schema-fill (Operation Catalog 0.4.0 -> 0.5.0, ratified first;
wire discriminants strictly appended):
- CreateStaff (24 / tag InsertStaff 24): set-union mint of a global
  Staff; CreateStaffInstance now preconditions that its referenced
  staff is live.
- SetTimeSignature (25): value-carrying meter-change LWW keyed by
  (region, resolved position); the carried TimeSignature mints
  set-union; StructuralFieldCollision on meter_sequence.
- SetTempoSegment (26): LWW keyed by (scope, resolved start) over
  the score or region tempo map; a write that would malform the map
  refuses with the appended PreconditionFailureReason 11
  (TempoMapMalformed).
- SetStaffLayout (27): LWW advisory over the staff instance's three
  inline layout fields.
- Create score/canvas remain deliberately unavailable slots: the
  root and canvas are inline singletons with no addressable object
  model (P12-K8), not force-designed.

Value-restoring undo (P11-C8 narrowed; catalog §UndoTransaction
rewritten and per-primitive undo notes updated):
- Canonical-order write chains (base-seeded) across all eleven LWW
  families. StrictInverse restores each written key to its
  chain-predecessor value iff the transaction's write is still the
  key's last writer, else refuses the whole undo with a
  TransactionConflict naming the superseder; BestEffort restores the
  still-last keys. Clean compensations are Applied; only minted-
  object tombstone repairs ride AppliedWithRepair (no new repair
  vocabulary). Mixed mint+overwrite transactions compose; strand
  guards refuse tombstoning mints still referenced by live
  non-members.
- Undo-of-undo pinned and tested: restorations are chain writes, so
  undoing the undo's transaction restores the undone value, and a
  second undo of the same transaction conflicts (absence-restores
  repeat idempotently — documented asymmetry, P12-K11).
- Permutation invariance pinned across five delivery orders; the
  convergence generators gain the new ops and a tx-then-undo flow.
- Still deferred in normative text: delete resurrection (needs a
  system-derived tag outside the ratified closed set), Transpose
  inversion (P12-K2), Cascade dependent closure.

Trackers: Binary Format companion 0.1.0 -> 0.2.0 (appended wire/tag
tables, PreconditionFailureReason 11, payload layouts, history row —
a schema-minor evolution under its own rules); nine new Pass-12 rows
(C5, K8-K11, I7-I10); core-spec OperationKind listing gains the four
kinds; revision-history rows in core spec and companion.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
2026-07-02 21:55:26 -04:00
Levi Neuwirth 3e91a8302a Push 4: Binary Format companion, F1 benches, subquadratic reduction order
The audit's fourth push: the biggest outstanding Phase-2 item plus the
performance gate. 793 workspace tests pass; clippy -D warnings, fmt,
and rustdoc (deny-warnings) clean; all three spec documents build with
zero undefined references.

Binary Format companion (spec/binary_format.tex, v0.1.0 — Agent J's
deliverable, 43 pages):
- Twelve chapters transcribed from the golden-locked implementation:
  encoding conventions (the three prefix/endianness regimes, a
  normative no-varint rule, reject-never-normalize decode discipline),
  identifiers imported from the core spec's Canonical Byte-Layout
  Reference, primitive value encodings, the whole-Score positional
  codec ratified as the schema-major-0 wire form, operation wire
  forms (envelope field order with the normative id-leads property,
  the OperationPayload 0..=3 and OperationKind 0..=23 tables,
  effects/conflict/anomaly/MaterializedState vocabulary), the bundle
  physical layout (64-byte header, 256-byte superblock, chunk
  preimages and framing, ChunkRef, manifest body order), the
  operation-index payload, and the extension-blob/edit-barrier byte
  forms.
- Ratifies P12-D1 (req:binfmt:opindex), P12-E1 (req:binfmt:ext-blobs),
  P12-E2 (req:binfmt:condition-depth, MAX_CONDITION_DEPTH = 64
  normative), and P12-E3 (req:binfmt:object-kind-open) — batch rows
  struck through; discharges the provisional-codec notes in core
  (P11-4), ops, and bundle (P11-D2/D4/D5) DECISIONS with ratification
  cross-references.
- Pins the frozen-layout schema-evolution keystone: within schema
  major 0 every positional struct layout is frozen; a field-set change
  is a schema-major change with migration — formally grounding the
  data-model-expansion staging decision. Open questions kept honest
  in-document: SnapshotId derivation, index-refresh threshold, u64/u32
  prefix unification at the next major.
- Not yet delivered from J's charter: the cross-implementation decoder
  test and the wire-format fuzzer (follow-up harnesses).

F1 benches (crates/epiphany-testkit/benches/, per the F0 decision):
- criterion 0.5.1 (workspace dev-dependency; MSRV 1.77 respected with
  documented transitive pins: clap 4.5.53, half 2.4.1).
- reduction bench at 1K/10K/50K envelopes with the Chapter-10 budget
  (>10,000 envelopes/second cold) written in the bench as a Pass/Xfail
  gate; bundle benches for the typical-edit commit (<=50 ms; measured
  ~14.7 ms on real disk after catching that tmpfs neuters fsync) and
  the open/bootstrap read (<=200 ms; measured ~60 us).
- CI: quick budget gates in the conformance job, full gates nightly.

Subquadratic canonical_reduction_order (the F-surfaces/K-fixes
handshake, closing K's 10K-envelope acceptance gate):
- The bench documented the failure (50K at ~1.7K env/s, a 29 s cold
  reduction; two O(n^2) loops); the fix replaces pair enumeration with
  threshold/frontier readiness per replica plus explicit-dot dependent
  lists and a stamp-tuple binary heap — O((n + sum(context)) log n),
  never materializing covered pairs.
- Byte-identical order: same edge relation, same ready predicate, same
  total order; the old implementation is retained as a test-only
  oracle with element-for-element order-equality property tests over
  fuzz sets, adversarial sets, and directed shapes (2,000-envelope
  full-coverage chains, dot cycles, duplicate-id stamp ties),
  mutation-tested for sensitivity.
- Measured: 1K 155K->674K env/s, 10K 12.5K->257K, 50K 1.7K->87K; all
  three scale points now pass and the 50K row is promoted from Xfail.

Also: fixed nine rustdoc private/unresolved intra-doc links that had
accumulated across the pushes (the CI deny-doc-warnings job would have
failed on them).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
2026-07-02 19:02:07 -04:00
Levi Neuwirth 92aaccf7e2 Pushes 1+3: fix the MUST-level violations, wire the types-only machinery
Two audit pushes whose code edits interleave line-by-line in the same
files (reduce.rs, bundle.rs, the DECISIONS logs), committed together so
the tree at every commit builds. Gate: 784 workspace tests pass, clippy
-D warnings clean, fmt clean.

Push 1 — the true MUST violations, all fixed:
- bundle: zstd read support on both read paths, output bounded by the
  declared uncompressed_length, typed decompression errors, explicit
  CompressedManifest rejection (zstd 0.13 workspace dep; write path
  stays uncompressed per the Phase-3 deferral).
- ops: system-derived counter collision check — mint registry seeded
  from the base graph, canonical-order pre-walk, halt via the new
  PendingReason::HaltedBySystemCollision (discriminant 4, additive)
  with transaction-atomicity and causal-dependent closure; neither
  input set occupies a collided counter. canonical_pitch_bytes made
  pub in core for the MUSCSPCH preimage.
- ops: Transpose skips tombstoned targets per the catalog; missing
  targets still refuse the whole operation.
- ops: marker re-anchoring recorded as a RepairRecord in the
  triggering operation's effect; ResolveConflict meta-conflicts name
  both resolvers; base-free pitch-id freshness; reserved effect
  vocabulary annotated.
- core: decomposition pre-pass honors authored attachments
  (resolve_decomposition, spec-default precedence); inversion
  tolerance typed as a TempoIntegration-class Tolerance.
- CONFORMANCE.md: the determinism conformance statement required by
  Appendix D — all seven declarations.

Push 3 — wiring the types-only machinery:
- layout-ir/engrave: to_constrained emits real constraints (successive
  notehead no-collision chains, per-glyph region containment, soft
  user-break constraints); ConstraintStrength{Required, Preferred}
  with strength-by-rule; Preferred violations surface as warnings, not
  failures; StubSolver reworked honest-but-renderable. SVG goldens
  byte-identical; snapshot constraint counts regenerated (0->90/15).
- layout-ir: to_logical projects user system/page breaks as anchored
  EngravingOverrides with paired UserOverride-sourced decisions
  (OverrideKind::SystemBreak/PageBreak carry TimeAnchor, ratified in
  the spec alongside).
- layout-ir/ops/editor-core: edit-barrier bridge — decode mirrors for
  the whole barrier tree (reject-never-normalize, NFC revalidation,
  MAX_CONDITION_DEPTH = 64), golden-locked blob codec for the
  ExtensionDeclaration fields, a barrier gate in apply and
  apply_transaction backed by a Score oracle and real containment
  contexts, and apply_unsafe recording the crossed extensions in
  extensions_requiring_tombstone() for the next bundle write.
- ops: ResolveEquivocation meta-operation per the newly ratified
  catalog entry — payload discriminant 3 (appended), set-level
  earliest-resolve-governs promotion, ResolveConflict-mirrored
  meta-conflicts, permutation-invariance fuzz; the missing golden
  locks on the OperationKind/OperationPayload wire tables added.
- ops/editor-core: validation modes — ValidationMode + a non-canonical
  advisory layer (validate.rs), an authoring gate before minting, and
  reduction pinned as replay mode by construction (canonical bytes
  untouched).
- bundle: the operation index (opindex.rs) — provisional golden-locked
  payload, binary-search locate, staleness defined as full-ChunkRef
  set equality against operation_roots, and the reject-and-rebuild
  discipline (a defective index is never bundle corruption).
- ops: re-anchoring rule table completed — the four-key "nearest"
  ordering computed from base-free ledger indices; markers re-anchor
  to the nearest live event in the same staff instance (replacing the
  Push-1 region-start stand-in); cue-source cascade; graphic-gesture
  Events/Range/Free rows; comment and analytical-annotation orphaning.
  Zero appended discriminants.

Spec enablers ratified with Push 3: catalog §ResolveEquivocation
(0.3.0 -> 0.4.0) and anchored break overrides; 16 new Pass-12 rows
filed (C1-C4, K5-K7, I4-I6, D1, E1-E5). The data-model payload
expansion (SlurKind, beam geometry, voltas, instrument bodies,
metadata) is deliberately staged to the Binary Format companion — the
positional graph codec has no value-level versioning, so filling those
structs is a schema-major break that should land once, with J.

Also carries the pre-existing editor-track increment: the atomic
tuplet overwrite (CascadeDeleteTuplets prunes decomposition
attachments naming the cascaded tuplet).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEs4aYiu8MXjdYdMxw8PTd
2026-07-02 17:10:50 -04:00
Levi Neuwirth 9539b1652b layout-ir, engrave: ledger lines
Notes above or below the staff now get ledger lines — the gap the GUI surfaced
the moment a note is moved off the staff. Each notehead carries its StaffStep;
to_constrained emits one short horizontal stroke per whole step between the
staff (lines at steps 0..=8) and the note, reaching LEDGER_LINE_EXTENSION past
each side of the note's actual bounding box (so a wide whole note gets a wider
ledger), synthesized from the pitch so the strokes are deterministic and
hit-testable. The synthesis key splits component (high 64 bits) from signed step
(low 64) so two components of a very low note can never collide.

Ledger lines are fixed-width marks, not system-spanning lines, so the Engraver's
horizontal spacing must not scale them. is_rigid_width_stroke marks them; the
remap translates such a stroke rigidly by its *owning glyph's* column delta
(found by source, not the stroke midpoint — which for a wide head can fall nearer
a neighbouring column), so it keeps both its length and its offset from the
notehead. The spacing pass folds each ledger's extent into its notehead's slot,
so adjacent off-staff notes' ledgers reserve room and do not overlap. The stub
solver passes ledgers through unchanged.

Tests cover the step geometry, key distinctness (incl. steps below -128), the
bbox span, width preservation and offset (no-drift) through the Engraver, the
adjacent-overlap spacing, and an explicit two-whole-note off-staff drift case.
Render goldens regenerated.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NAtEiJtt9yKVV1zjKYmZhS
2026-06-29 17:12:56 -04:00
Levi Neuwirth 3ef1a8abd9 Pass-12 batch: mark the resolved I-series rows done
A status sweep: the I-series Pass-12 candidates are all closed, but the tracker
and two crate DECISIONS.md files still described them as open.

  - PASS12_BATCH.md: P12-I1 (structural-placeholder pipeline) is resolved by I-1
    -- to_constrained now builds real notation and the Engraver re-spaces it;
    P12-I3 (BRAVURA_METRICS approximations) is resolved by I-4a -- metrics
    re-extracted from the same pinned 1.392 font, containment-tested. Both rows
    struck through and marked done.
  - render-svg/DECISIONS.md: fixed the stale P12-I2 bullet, which still said the
    MUSCLOID derivation was unwired and the determinism crate exposed no tag (a
    miss from the P12-I2 commit); now marked resolved.
  - engrave/DECISIONS.md: its P12 section described P12-I1/I3 as open and omitted
    I2; rewritten so all three read resolved.

The batch's top-level Status stays OPEN -- the H-series and K-series candidates
remain. Docs-only; no code change.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-27 12:53:36 -04:00
Levi Neuwirth e2d389330d P12-I2: wire the ratified MUSCLOID layout-object id derivation
The spec's domain-tag registry reserves a non-canonical MUSCLOID layout tag for
LayoutObjectId derivation (req:layoutir:object-id-derivation, Pass-11 item 2.6),
but it was never realized in code: layout-ir minted provisional, untagged ids and
synthesized objects borrowed MUSCCONF. This wires the ratified derivation.

  - epiphany-determinism: add the reserved built-in DomainTag::LAYOUT_OBJECT_ID
    (`MUSCLOID`), non-canonical/layout-namespace like FONT_METRICS (following the
    SYSTEM_ANOMALY Pass-11 precedent of adding a reserved tag). The tag-enumeration
    tests now derive from BUILTINS so they cannot drift; the spelling is locked and
    from_bytes resolves it as a non-system builtin.
  - layout-ir provenance.rs: all three LayoutObjectId derivations route through
    MUSCLOID exactly per the requirement -- single keyed on source.canonical_bytes(),
    multiply-manifested on (source, region), synthesized on (source, synthesis_kind,
    instance_key); synthesized no longer borrows MUSCCONF. A reference-lock test
    pins the derivation and proves it is genuinely domain-separated; another asserts
    the three keying schemes do not collide (safe by the discriminant-led,
    fixed-width canonical_bytes).
  - layout-ir engraving.rs: EngravingDecisionId borrowed MUSCCONF for the same
    reason; moved it onto MUSCLOID too, keeping its `engraving-decision` prefix so it
    cannot alias a layout-object id within the namespace.

Layout ids are non-canonical (never document state, in no content hash), so this
changed id *values* but no durable or interchanged artifact: the only golden churn
is the data-prov hex in the four render goldens (every changed line is a data-prov;
geometry/structure byte-identical).

Spec/status sync: core_spec.tex descriptive notes (the requirement tail, the
domain-tag registry row, the registry intro, and the revision-history entry) now
say the reference implementation wires MUSCLOID as of P12-I2; MUSCLOID is moved out
of the "deferred to the companions" (not-ratified/provisional) list and given a
non-canonical anchor paragraph after the reference-implementation-locks table.
PASS12_BATCH.md marks P12-I2 resolved; PASS11_RATIFICATION_LOG.md keeps the
historical row with a "superseded by P12-I2" note; layout-ir/DECISIONS.md updates
the ratified-block note, the id bullet, and the open candidate (now RESOLVED).

Full gate green: build, fmt, clippy, 587 tests, conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-27 12:46:19 -04:00
Levi Neuwirth 6293734fa0 Agent I-4c: embedded @font-face glyph mode (a second self-contained renderer)
A render mode that references each glyph by its SMuFL codepoint via `<text>`,
drawn from an `@font-face`-embedded Bravura subset, alongside the default inline
`<path>` outlines. The SVG stays self-contained (the font travels in it) and the
text is selectable, at a larger file size.

  - GlyphMode::EmbeddedFont: the SVG declares the font once via
    <defs><style>@font-face{...}</style></defs>, then emits one
    <text transform="translate(x y) scale(1 -1)" font-size="4" ...>&#xNNNN;</text>
    per glyph. Geometry is consistent with PathOutline by construction: same
    origin, a per-glyph counter-flip cancels the outer y-flip, and the SMuFL em is
    four staff spaces. A new `text_count` stat; unbundled glyphs still fall through
    to the visible bbox rect + diagnostic. The metadata comment declares which mode
    produced the SVG (and, on the empty canvas too, via a shared `glyph_note`).
    Path mode stays the byte-golden-locked, pixel-verified reference; the embedded
    mode is structurally tested (well-formed XML — also under `xmllint`; one
    @font-face; one <text>/codepoint per glyph; provenance preserved; determinism).

  - The subset is a GENERATED artifact, not a vendored binary: a deterministic
    base64 OTF emitted into src/font_subset_generated.rs by
    `tools/extract_bravura_outlines.py --font-out` (the same SHA-pinned 1.392 font
    the outlines come from). `recalcTimestamp=False` keeps the source font's fixed
    head.modified so the bytes are reproducible across runs, not just within one.

  - OFL compliance: the subset is a Modified Version, so its PRIMARY font name is
    renamed off the Reserved Font Name "Bravura" to "EpiphanyBravuraSubset" in BOTH
    naming structures an OTF carries — the SFNT `name` table AND the CFF (Name INDEX
    + top-dict FullName/FamilyName). The copyright/trademark/license records, which
    name Bravura as attribution, are kept; the renderer references the renamed
    family in @font-face and <text>. The generator reparses the saved bytes and
    fails if the reserved name leaks into a primary record, and validates the cmap
    covers every glyph.

  - Machine-locked payload: the generator emits the decoded length and a BLAKE3-256
    (the workspace's sole hash) of the font bytes; a render-svg test base64-decodes
    the payload (no new runtime dep) and asserts the length, the OTTO signature, the
    BLAKE3, and — parsing the SFNT name table and CFF Name INDEX — that neither
    primary name is the reserved name. Adds an epiphany-determinism dev-dep.

The demo example gains `--glyph-mode=path|embedded`; lib/README/DECISIONS document
the two modes, the subset's OFL rename, and the regeneration command (--font-out +
the blake3 dependency). PathOutline goldens are byte-unchanged; the outlines stay
byte-identical. Full gate green: build, fmt, clippy, 585 tests, conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-27 11:09:34 -04:00
Levi Neuwirth 41cd8bf58b Agent I-4b: a trace-free render declares itself display-only
`RenderOptions::emit_provenance = false` dropped every data-prov trace silently,
so the output was indistinguishable from an archival render even though it no
longer satisfies the renderer's "every element traces to its source" contract.

Now the SVG's metadata comment declares the provenance state, so suppression is
announced rather than silent:

  - archival (default):    "...; every glyph and stroke carries a data-prov trace
                            to its score-graph source"
  - display-only (false):  "...; provenance traces suppressed (display-only
                            output, not archival)"

A shared `provenance_note(emit_provenance)` helper feeds both the main render and
the empty-canvas path, so an empty trace-free layout is held to the same honesty
contract as a full one (neither can drift). The module doc and the render-svg
DECISIONS.md non-overreach rule now frame data-prov as the default archival
contract plus an explicit, declared display-only mode. Tests assert the suppressed
marker (full and empty layouts) and that the default render declares traces
present.

Goldens regenerated: the default (archival) render's metadata comment now carries
the new "every glyph and stroke carries a data-prov trace" clause, so the four
`.svg` goldens change by that one line (the snapshots, which omit the comment, do
not). Full gate green: build, fmt, clippy, 581 tests, conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-27 09:47:35 -04:00
Levi Neuwirth eec63aa244 Agent I-4a: reconcile the Bravura metrics with the 1.392 outlines
The layout metrics table claimed Bravura 1.38.0 while the renderer's outlines are
extracted from 1.392, so the advances/bboxes the engraver reserves space and
evaluates collisions from did not match the ink actually drawn (P12-I3). Both now
come from the SAME SHA-pinned bravura-1.392 font.

  - BRAVURA_METRICS is regenerated from 1.392 by tools/extract_bravura_outlines.py
    (the same font and script the outlines come from; the regenerated outlines are
    byte-identical to the committed ones, and the extracted timeSig rows match the
    values bundled earlier -- two integrity checks that the extraction is faithful).
    Several old rows were not just stale but wrong: flag8thUp had its ink above the
    origin when the glyph hangs below the stem tip; restWhole/restHalf and the
    clefs had approximate or mis-signed bounds.
  - The metric bbox is rounded OUTWARD from the outline bounds (floor the mins,
    ceil the maxes) rather than to the nearest 1/1024, so the integer metric box
    always CONTAINS the drawn outline -- the engraver evaluates collisions from
    that box, and a containing box keeps a hard no-collision result honest on
    paper. A new render-svg test (metric_bboxes_contain_the_drawn_outlines) proves
    the containment for every bundled glyph, so a future re-extraction cannot
    silently regress it.
  - BRAVURA_VERSION is 1.38.0 -> the literal font version: name-table ID 5 reads
    "Version 1.392" and head.fontRevision ~= 1.392 (a single decimal), recorded
    verbatim as SemVer { major: 1, minor: 392, patch: 0 } so the identifier
    round-trips to the font's own string. The canonical mapping rule is documented
    on BRAVURA_VERSION; DECISIONS.md is updated to match.

The corrected metrics surfaced a coupled placement bug: the old barlineSingle
metric falsely centred the glyph (+/-2048), so the bottom-origin Bravura barline
(which runs 0..4 staff spaces UP from its origin) was anchored at staff-centre and
floated above the midline. It is now anchored at the staff bottom (yo), so a
barline connects the bottom and top staff lines.

Goldens regenerated (stub + engrave) for the corrected geometry. Full gate green:
build, fmt, clippy, 581 tests, conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-26 22:45:33 -04:00
Levi Neuwirth af297881e2 Agent I-3: criterion-6 round-trip and golden lock on the real Engraver
Criterion 6 (the Chapter 7 layout round-trip) and the render goldens previously
exercised only the verbatim StubSolver, so a regression in the real Engraver's
geometry could land unseen. I-3 drives both through the Engraver.

  - round_trip_with<S: ConstraintSolver> factors the solver-agnostic provenance
    contract out of round_trip (now a one-line stub wrapper): coverage, the
    complete Provenance surviving constrained -> resolved -> render, the source
    surjection, and no duplicate stable ids hold for *any* conformant solver. The
    Stub tier's verbatim-geometry clause is gated behind solver.tier() == Stub;
    every other tier re-spaces. The status gate accepts any renderable status
    (Solved / SolvedWithWarnings / PartialBudgetExhausted), not exactly Solved, so
    the helper matches its "arbitrary conformant solver" contract while still
    rejecting the diagnostic-only statuses that carry no authoritative layout.
  - criterion_six_round_trips_through_the_engravers_respacing (epiphany-engrave)
    runs the full graph -> logical -> constrained -> *engraved* -> render round
    trip over the criterion-6 hand-off fixtures -- ten_measure_single_staff (the
    measured fixture) and valid_score_rich (cross-cutting tuplet/tie/spanner),
    plus valid_score for breadth -- and asserts the whole provenance contract
    survives the Engraver's re-spacing. A non-vacuity check confirms the Engraver
    genuinely moved geometry, so provenance is preserved *through* a real geometry
    change -- the statement the verbatim stub can never make. This adds an
    epiphany-testkit dev-dep (no cycle: testkit does not depend on this crate).
  - The render-svg engraver acceptance test is upgraded from invariant-only to
    byte-locked: new .engrave.snapshot.txt / .engrave.svg goldens for both
    fixtures capture the Engraver's re-spaced output (e.g. ten_measure view_box
    width 82.26 vs the stub's 88.88, same glyph/stroke/class counts), so an
    Engraver geometry regression is caught at the byte level. A companion test
    asserts the engrave goldens genuinely differ from the stub goldens, catching
    the degeneracy where the Engraver echoes the stub (which would otherwise pass
    both golden checks independently).

Also corrects the epiphany-engrave package description, which still claimed it
reports SolverTier::Stub until it earns Minimal (it earned Minimal in I-2).

Full gate green: build, fmt, clippy, 580 tests, conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-26 21:58:31 -04:00
Levi Neuwirth 91c9f01bb5 Agent I Phase 2-3: engrave recognizable notation from Score to SVG
Turn the Score -> layout-IR -> SVG pipeline from placeholder glyphs into real
music notation, rendered through the stub solver and the real Engraver alike.

to_constrained (the spacing pass) now dispatches each layout object to the
notation primitive that represents it, on a column-based spring model:

  - Pitch -> notehead at its clef-relative staff position; chord pitches share
    one column slot. StaffInstance -> clef glyph. Staff -> five staff-line
    strokes (the bottom line its anchor, four synthesized). Pitched Event ->
    stem stroke; Measure -> barline glyph; rest Event -> rest glyph.
  - Phase 3 ornaments as synthesized glyphs: a spelling's full accidental stack
    left of its notehead, a key signature's clef-relative sharp/flat zigzag in
    the lead, and a measure's numerator/denominator time-signature digit pair.
  - A tied decomposition draws one notehead/stem/rest per component (offsets
    honored, not collapsed). Active clef and key resolve by time, not vector
    order. The lead area reserves clef + key-signature width.
  - Coverage/surjection preserved so the round-trip holds: each laid-out object
    is covered by exactly one exact-provenance primitive, and derived primitives
    (staff lines, components, accidentals, key/time glyphs) are synthesized from
    a laid-out source. Engraving-coverage gaps (missing spelling, unbundled
    glyph) are surfaced as ConstrainedLayoutIR diagnostics, not silently
    defaulted. A measure depends on the time signature it displays.

The Engraver re-spaces glyphs AND the strokes that track them through one
collision-aware coordinate map (per-slot left/right bearings, pairwise
advances), so stems / barlines / staff lines stay attached and a note's
accidental never overlaps the previous note. validate() now rejects empty
spring slots -- the contract that map relies on -- and to_constrained never
emits one (slots are realized by glyph occupancy).

Bundle the genuine Bravura outlines and metrics for time-signature digits 0-9
(regenerated from the SHA-pinned font via tools/extract_bravura_outlines.py),
replacing an inconsistent hand-written placeholder.

Regions tile left-to-right (no page casting-off yet). Goldens regenerated into
recognizable notation. Full gate green: build, fmt, clippy, 574 tests,
conformance scale 1.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-26 20:46:33 -04:00
Levi Neuwirth ac7c076e73 Phase 2 (Agent I): visible-slice scaffold — Bravura SVG renderer vs stub
Lands the renderer-against-stub slice of Agent I's visible engraving work
(spec/PHASE2_QUICKSTART.md). Two new crates; prerequisites (G Pass 11, H
spelling/decomposition) are in place. Real engraving + Minimal-tier solver
follow next phase.

epiphany-render-svg (the deliverable this phase):
- Renders a ResolvedLayoutIR to well-formed SVG 1.1, drawing each glyph as a
  GENUINE Bravura SMuFL outline <path>. Outlines are extracted reproducibly
  from the official OFL Bravura.otf by a committed generator
  (tools/extract_bravura_outlines.py, OFL.txt); the font is not vendored, only
  the generated Rust (src/outlines_generated.rs). Staff-space/y-up coords with
  one global y-flip wrapper; viewBox in staff spaces, px scale on the root.
- Non-overreach: every element traces to a ResolvedGlyph (data-prov) or a
  declared wrapper; a glyph lacking an outline is surfaced as a diagnostic and
  drawn as a fallback rect, never silently dropped.
- Hand-rolled xml::check_well_formed (no XML dep); acceptance tests cross-check
  with system xmllint when present.
- examples/render_fixture.rs demo (fixture name -> SVG stdout, --solver=stub|real).
- Golden-locked machine acceptance snapshot + full-SVG golden for
  ten_measure_single_staff and valid_score_rich; deterministic output.

epiphany-engrave (honest scaffold):
- Engraver: a deterministic horizontal-spacing pass (first axis of the planned
  two-pass spring layout). Reports SolverTier::Stub — NOT Minimal — until it
  evaluates the declared hard constraints, guarded by a regression test. The
  demo's --solver=real exercises it end to end.

Honesty notes (recorded as Pass-12 candidates P12-I1..I3 in spec/PASS12_BATCH.md
and the crates' DECISIONS.md): the v0 to_logical/to_constrained pipeline is a
structural placeholder (arbitrary glyph per object, y=0), so stub output is not
yet recognizable notation and the QUICKSTART human visual gate is a next-phase
gate; MUSCLOID layout-id derivation stays unwired; bundled BRAVURA_METRICS are
approximations that disagree with the real outlines.

Gates: cargo fmt + clippy -D warnings clean; cargo test --workspace 504 passed,
0 failed, 0 ignored (criterion 6 layout round-trip still green).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-23 20:01:40 -04:00