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>
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
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
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