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>
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>
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>
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>
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
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>
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>
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>
Levi Neuwirth