Playback Mode Pages

generator/engraving/audit.py

@@ -79,6 +79,9 @@ def audit_layout(document: dict, layout: generator.engraving.types.LayoutDocumen
       # Staff, ledger, stem, beam and tie contacts are intentional. Distinct
       # noteheads, accidentals and text in the same lane must remain separate.
       checked = [p for p in system.primitives if p.role in ('head', 'tab', 'accidental', 'harmony', 'lyric', 'scale', 'section')]
+      for label in (p for p in system.primitives if p.role == 'measure_number'):
+        if any(label.box.overlaps(p.box, 3 * system.scale) for p in system.primitives if p is not label):
+          raise generator.engraving.types.EngravingError(f'{label.sources}: measure number overlaps notation')
       for i, item in enumerate(checked):
         for other in checked[i + 1:]:
           if set(item.sources) & set(other.sources) and (item.role != 'tab' or other.role != 'tab'):
@@ -141,3 +144,29 @@ def audit_layout(document: dict, layout: generator.engraving.types.LayoutDocumen
   for span in index.staff.get('octave_shifts', []):
     if not any(p.role == 'octave-shift' for p in primitives.get(span['id'], [])):
       raise generator.engraving.types.EngravingError(f'{span["id"]}: octave shift was omitted')
+
+def audit_playback(pages, playback, style, fonts):
+  canonical = [system for page in pages for system in page.systems]
+  if len(playback) != len(canonical):
+    raise generator.engraving.types.EngravingError('playback must have one view per system')
+  for i, page in enumerate(playback):
+    audit_primitives(page.primitives, page.width, page.height, fonts)
+    expected = canonical[i:i + 2]
+    if len(page.systems) != len(expected):
+      raise generator.engraving.types.EngravingError('invalid playback system pairing')
+    header = generator.engraving.types.bounds([p for p in page.primitives if p.role in ('title', 'subtitle')])
+    footer = generator.engraving.types.bounds([p for p in page.primitives if p.role == 'page_number'])
+    if page.systems[0].box.top < header.bottom + style.page_clearance - 0.01 or page.systems[-1].box.bottom > footer.top - style.page_clearance + 0.01:
+      raise generator.engraving.types.EngravingError('playback overlaps header or footer')
+    for a, b in zip(page.systems, page.systems[1:]):
+      if a.box.bottom + style.system_gap > b.box.top + 0.01:
+        raise generator.engraving.types.EngravingError('playback systems overlap')
+    for source, actual in zip(expected, page.systems):
+      if (source.start, source.end, source.scale, source.fragments) != (actual.start, actual.end, actual.scale, actual.fragments):
+        raise generator.engraving.types.EngravingError('playback changes system content')
+      dy = actual.box.top - source.box.top
+      if len(source.primitives) != len(actual.primitives):
+        raise generator.engraving.types.EngravingError('playback changes primitives')
+      for a, b in zip(source.primitives, actual.primitives):
+        if (a.kind, a.role, a.sources, a.value, a.size) != (b.kind, b.role, b.sources, b.value, b.size) or len(a.points) != len(b.points) or any(abs(x - u) > .001 or abs(y + dy - v) > .001 for (x, y), (u, v) in zip(a.points, b.points)):
+          raise generator.engraving.types.EngravingError('playback changes notation geometry')

generator/engraving/cache.py

@@ -61,7 +61,7 @@ def restore_pages(entry: pathlib.Path, destination: pathlib.Path, validated_page
       return None
     destination.mkdir(parents=True, exist_ok=True)
     for index, page in enumerate(pages, 1):
-      if not isinstance(page, dict) or set(page) != {'path', 'sha256', 'first_measure', 'measure_count', 'start_beat', 'end_beat'} or page['path'] != f'{index:04}.png' or not isinstance(page['sha256'], str) or not re.fullmatch('[0-9a-f]{64}', page['sha256']):
+      if not isinstance(page, dict) or set(page) != {'path', 'sha256', 'first_measure', 'measure_count', 'start_beat', 'end_beat', 'systems', 'playback'} or type(page['playback']) is not bool or not isinstance(page['path'], str) or not re.fullmatch(r'(?:playback-)?[0-9]{4,5}\.png', page['path']) or not isinstance(page['sha256'], str) or not re.fullmatch('[0-9a-f]{64}', page['sha256']):
         return None
       path = entry / page['path']
       if path.is_symlink() or not path.is_file():
@@ -88,7 +88,7 @@ def store_pages(entry: pathlib.Path, destination: pathlib.Path, pages: list[dict
       shutil.copyfile(destination / page['path'], staged / page['path'])
     (staged / 'pages.json').write_text(json.dumps(pages), encoding='utf-8')
     # Identical keys have identical pages; publish complete files, then the manifest.
-    for name in [page['path'] for page in pages] + ['pages.json']:
+    for name in list(dict.fromkeys(page['path'] for page in pages)) + ['pages.json']:
       target = entry / name
       if target.is_dir() and not target.is_symlink():
         shutil.rmtree(target, ignore_errors=True)

generator/engraving/layout.py

@@ -57,7 +57,6 @@ def column(index: generator.engraving.notation.ScoreIndex, time: fractions.Fract
       items.append(fonts.text(generator.harmony.symbol(item), 0, 0, 18 if index.staff.get('tablature') else 21, 'harmony', (item['id'],)))
   items.extend(generator.engraving.scales.column(index, time, start, fonts))
   if time == measure_start:
-    items.append(fonts.text(str(measure['number']), 0, -style.space * (index.state(time)['staff_details']['lines'] + 0.5), 12, 'measure_number', (measure['id'],)))
     if label := measure.get('section_label'):
       items.append(fonts.text(label, 0, 0, 16 if index.staff.get('tablature') else 19, 'section', (measure['id'] + ':section',)))
   return items, anchors, fragments
@@ -103,6 +102,10 @@ def make_system(index: generator.engraving.notation.ScoreIndex, start: fractions
       for owner, ci, change in index.attributes_by_onset.get(time, []):
         extra = generator.engraving.attributes.staff_attributes(index, index.state(time), time, fonts, style.space, owner['id'] + f':attributes:{ci}', tuple(change))
         leading.extend(p.moved(max((p.box.right for p in leading), default=0) + 10, 0) for p in extra)
+    if time == measure_start:
+      # Anchor labels to the barline, not to the first note's time column.
+      bar_x = cursor - generator.engraving.types.bounds(leading).left if leading else 0
+      items.append(fonts.text(str(m['number']), bar_x, 0, 12, 'measure_number', (m['id'],), True))
     if leading:
       width = generator.engraving.types.bounds(leading).right - generator.engraving.types.bounds(leading).left + 14
       items.extend(p.moved(cursor - generator.engraving.types.bounds(leading).left, 0) for p in leading)
@@ -162,7 +165,7 @@ def fit_part_systems(systems, index, available_height, fonts, style):
 
   def fitting_scale(items):
     scale = 1
-    for first in range(0, len(items), 2):
+    for first in range(len(items)):
       pair = items[first:first + 2]
       height = sum(s.box.bottom - s.box.top for s in pair)
       scale = min(scale, (available_height - style.system_gap * (len(pair) - 1)) / height)
@@ -214,30 +217,36 @@ def part_header(document, fonts, style):
   result.append(fonts.text(line, style.margin_x, baseline, 12, 'subtitle', ()))
   return result
 
-def paginate(systems: list[generator.engraving.types.System], document: dict, fonts: generator.engraving.fonts.Fonts, style: generator.engraving.types.Style, *, index=None) -> tuple[generator.engraving.types.Page, ...]:
-  pages = []
+def page_views(systems: list[generator.engraving.types.System], document: dict, fonts: generator.engraving.fonts.Fonts, style: generator.engraving.types.Style, *, index=None) -> tuple[tuple[generator.engraving.types.Page, ...], tuple[generator.engraving.types.Page, ...]]:
   index = index or generator.engraving.notation.ScoreIndex(document)
   header = part_header(document, fonts, style)
   top = generator.engraving.types.bounds(header).bottom + style.page_clearance
-  footers = [fonts.text(str(number), style.width / 2, style.height - style.margin_y, 12, 'page_number', (), True) for number in range(1, (len(systems) + 1) // 2 + 1)]
+  footers = [fonts.text(str(number), style.width / 2, style.height - style.margin_y, 12, 'page_number', (), True) for number in range(1, len(systems) + 1)]
   bottom = min(p.box.top for p in footers) - style.page_clearance
   if bottom - top <= style.system_gap:
     raise generator.engraving.types.EngravingError('page header leaves no room for two music systems')
   fitted = fit_part_systems(systems, index, bottom - top, fonts, style)
-  for first in range(0, len(systems), 2):
-    number = len(pages) + 1
-    pair = fitted[first:first + 2]
-    slack = max(0, bottom - top - sum(s.box.bottom - s.box.top for s in pair) - style.system_gap * (len(pair) - 1))
-    spacing = slack / 3 if len(pair) == 2 else 0
-    cursor = top + spacing
-    placed = []
-    for system in pair:
-      dx, dy = style.margin_x + 1, cursor - system.box.top
-      placed.append(dataclasses.replace(system, primitives=tuple(p.moved(dx, dy) for p in system.primitives), anchors=tuple(a.moved(dx, dy) for a in system.anchors), box=system.box.moved(dx, dy)))
-      cursor = placed[-1].box.bottom + style.system_gap + spacing
-    footer = footers[first // 2]
-    pages.append(generator.engraving.types.Page(number, style.width, style.height, style.supersampling, tuple(placed), tuple(header + [p for s in placed for p in s.primitives] + [footer])))
-  return tuple(pages)
+
+  def place(stride):
+    pages = []
+    for first in range(0, len(fitted), stride):
+      number = len(pages) + 1
+      pair = fitted[first:first + 2]
+      slack = max(0, bottom - top - sum(s.box.bottom - s.box.top for s in pair) - style.system_gap * (len(pair) - 1))
+      spacing = slack / 3 if len(pair) == 2 else 0
+      cursor = top + spacing
+      placed = []
+      for system in pair:
+        dx, dy = style.margin_x + 1, cursor - system.box.top
+        placed.append(dataclasses.replace(system, primitives=tuple(p.moved(dx, dy) for p in system.primitives), anchors=tuple(a.moved(dx, dy) for a in system.anchors), box=system.box.moved(dx, dy)))
+        cursor = placed[-1].box.bottom + style.system_gap + spacing
+      pages.append(generator.engraving.types.Page(number, style.width, style.height, style.supersampling, tuple(placed), tuple(header + [p for s in placed for p in s.primitives] + [footers[number - 1]])))
+    return tuple(pages)
+
+  return place(2), place(1)
+
+def paginate(systems, document, fonts, style, *, index=None):
+  return page_views(systems, document, fonts, style, index=index)[0]
 
 def layout_systems(document: dict, style: generator.engraving.types.Style, fonts: generator.engraving.fonts.Fonts, *, index=None) -> tuple[generator.engraving.types.System, ...]:
   if index is None:

generator/engraving/pipeline.py

@@ -101,14 +101,19 @@ def clear_pages(destination):
     shutil.rmtree(destination)
 
 def write_bundle(path, document, pages, fingerprint):
-  entries = [{**page, 'path': path.with_suffix('.pages').name + '/' + page['path']} for page in pages]
+  entries = [{k: v for k, v in {**page, 'path': path.with_suffix('.pages').name + '/' + page['path']}.items() if k != 'playback'} for page in pages]
+  normal = [entry for entry, page in zip(entries, pages) if not page['playback']]
+  playback = [entry for entry, page in zip(entries, pages) if page['playback']]
   music = document
   bundle = {'music': music, 'presentation': {'engine': generator.engraving.validation.ENGINE_NAME, 'style_sha256': fingerprint,
-    'width': generator.engraving.validation.PAGE_WIDTH, 'height': generator.engraving.validation.PAGE_HEIGHT, 'pages': entries}}
-  generator.performance.validate_pages(document, pages)
+    'width': generator.engraving.validation.PAGE_WIDTH, 'height': generator.engraving.validation.PAGE_HEIGHT, 'pages': normal, 'playback_pages': playback}}
+  validate_cached_views(document, pages)
   bundle['performance'] = generator.performance.timing(document)
   path.write_text(json.dumps(bundle, indent=2, ensure_ascii=False) + '\n', encoding='utf-8')
 
+def validate_cached_views(document, pages):
+  generator.performance.validate_views(document, [p for p in pages if not p['playback']], [p for p in pages if p['playback']])
+
 def engrave_group(notation, paths, root, font_path, cache_dir, fingerprint, progress=False):
   family = generator.engraving.fonts.Fonts(font_path)
   style = generator.engraving.types.Style()
@@ -140,19 +145,25 @@ def engrave_group(notation, paths, root, font_path, cache_dir, fingerprint, prog
               systems = generator.engraving.layout.layout_systems(document, style, family, index=index)
               result.timings['layout'] += time.monotonic() - started
             started = time.monotonic()
-            pages_layout = generator.engraving.layout.paginate(systems, document, family, style, index=index)
+            pages_layout, playback_layout = generator.engraving.layout.page_views(systems, document, family, style, index=index)
             placement = tuple((page.width, page.height, tuple((system.start, system.end, system.box) for system in page.systems)) for page in pages_layout)
             if placement not in audited:
               layout = generator.engraving.types.LayoutDocument(pages_layout, style, fingerprint)
               generator.engraving.audit.audit_layout(document, layout, family)
+              generator.engraving.audit.audit_playback(pages_layout, playback_layout, style, family)
               audited.add(placement)
             else:
-              for page in pages_layout:
+              for page in pages_layout + playback_layout:
                 decoration = tuple(p for p in page.primitives if p.role in ('title', 'subtitle', 'page_number'))
                 generator.engraving.audit.audit_primitives(decoration, page.width, page.height, family)
             result.timings['pagination'] += time.monotonic() - started
             pages = []
-            for page in pages_layout:
+            rendered = {}
+            for is_playback, page in [(False, p) for p in pages_layout] + [(True, p) for p in playback_layout]:
+              if page.primitives in rendered:
+                name, digest = rendered[page.primitives]
+                pages.append(dict(path=name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
+                continue
               bands = generator.engraving.raster.page_bands(page)
               if bands is None:
                 started = time.monotonic()
@@ -161,12 +172,14 @@ def engrave_group(notation, paths, root, font_path, cache_dir, fingerprint, prog
                 body = bodies.get(notation, page, bands[1], family)
                 started = time.monotonic()
                 image = generator.engraving.raster.compose_page(page, family, bands, body)
-              target = destination / f'{page.number:04}.png'
+              target = destination / (('playback-' if is_playback else '') + f'{page.number:04}.png')
               with image:
                 image.save(target, format='PNG')
               result.timings['raster'] += time.monotonic() - started
               result.renderedpages += 1
-              pages.append({'path': target.name, 'sha256': hashlib.sha256(target.read_bytes()).hexdigest(), **generator.performance.page_timing(document, page)})
+              digest = hashlib.sha256(target.read_bytes()).hexdigest()
+              rendered[page.primitives] = target.name, digest
+              pages.append(dict(path=target.name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
             scores[score_key] = (destination, pages)
           write_bundle(path, document, pages, fingerprint)
           result.scores.append((path, score_key, pages))
@@ -213,7 +226,7 @@ def engrave_tree(root: pathlib.Path, fonts: pathlib.Path, *, cache_dir: pathlib.
       pages = generator.engraving.cache.restore_pages(entry, destination, validated_pages) if entry else None
       if pages is not None:
         try:
-          generator.performance.validate_pages(document, pages)
+          validate_cached_views(document, pages)
         except (ValueError, TypeError, KeyError):
           pages = None
       if pages is None:

generator/engraving/spans.py

@@ -123,7 +123,7 @@ def draw_spans(index: generator.engraving.notation.ScoreIndex, anchors: list[gen
       y = anchor.y - anchor.direction * 8
       if anchor.x - 2 > left:
         result.append(generator.engraving.types.curve('tie', (identifier,), ((left, y), (left + 5, y - anchor.direction * 9), (anchor.x - 7, y - anchor.direction * 9), (anchor.x - 2, y)), 1.6))
-  top = min(-style.space * 5, min((p.box.top for p in items if p.role not in ('harmony', 'lyric', 'section', 'scale', 'tempo')), default=0))
+  top = min(-style.space * 5, min((p.box.top for p in items if p.role not in ('harmony', 'lyric', 'section', 'scale', 'tempo', 'measure_number')), default=0))
   tuplet_lanes = []
   for span in index.staff.get('tuplets', []):
     a, b = index.by_id[span['start']], index.by_id[span['end']]
@@ -203,11 +203,11 @@ def draw_spans(index: generator.engraving.notation.ScoreIndex, anchors: list[gen
   return items + result
 
 def place_text_lanes(items: list[generator.engraving.types.Primitive], fonts: generator.engraving.fonts.Fonts, style: generator.engraving.types.Style) -> list[generator.engraving.types.Primitive]:
-  music = [p for p in items if p.role not in ('harmony', 'lyric', 'section', 'scale')]
+  music = [p for p in items if p.role not in ('harmony', 'lyric', 'section', 'scale', 'measure_number')]
   box = generator.engraving.types.bounds(music)
   result = list(music)
   top = box.top - 12
-  for role in ('harmony', 'scale', 'section'):
+  for role in ('measure_number', 'harmony', 'scale', 'section'):
     lane = [p for p in items if p.role == role]
     if lane:
       extent = generator.engraving.types.bounds(lane)

generator/performance.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 import fractions
 import hashlib
 import json
+import math
 import pathlib
 import re
 import shutil
@@ -23,7 +24,63 @@ def page_timing(document, page):
   times = boundaries(document)
   start, end = page.systems[0].start, page.systems[-1].end
   first, last = times.index(start), times.index(end)
-  return dict(first_measure=first + 1, measure_count=last - first, start_beat=generator.model.rational(start), end_beat=generator.model.rational(end))
+  measures = document['staves'][0]['measures']
+  systems = []
+  for system in page.systems:
+    a, b = times.index(system.start), times.index(system.end)
+    labels = {p.sources[0]: p for p in system.primitives if p.role == 'measure_number'}
+    boxes = []
+    for i in range(a, b):
+      box = labels[measures[i]['id']].box
+      boxes.append(dict(measure=i + 1, bounds=[box.left, box.top, box.right, box.bottom]))
+    systems.append(dict(first_measure=a + 1, measure_count=b - a, start_beat=generator.model.rational(system.start), end_beat=generator.model.rational(system.end), labels=boxes))
+  return dict(first_measure=first + 1, measure_count=last - first, start_beat=generator.model.rational(start), end_beat=generator.model.rational(end), systems=systems)
+
+def validate_views(document, pages, playback_pages):
+  validate_pages(document, pages)
+  times = boundaries(document)
+  canonical = []
+
+  def system_range(system):
+    a, count = system['first_measure'], system['measure_count']
+    if type(a) is not int or type(count) is not int or a < 1 or count < 1 or a + count > len(times):
+      raise ValueError('invalid system measure coverage')
+    if generator.model.fraction(system['start_beat']) != times[a - 1] or generator.model.fraction(system['end_beat']) != times[a + count - 1]:
+      raise ValueError('invalid system timing')
+    if [label['measure'] for label in system['labels']] != list(range(a, a + count)):
+      raise ValueError('invalid measure label coverage')
+    for label in system['labels']:
+      box = label['bounds']
+      if not isinstance(box, list) or len(box) != 4 or any(type(v) not in (int, float) or not math.isfinite(v) for v in box) or not (4 <= box[0] < box[2] <= 972 and 4 <= box[1] < box[3] <= 480):
+        raise ValueError('invalid measure label bounds')
+    return a, count
+
+  for page in pages:
+    systems = page.get('systems', [])
+    if len(systems) != 2 and (page is not pages[-1] or len(systems) != 1):
+      raise ValueError('invalid page systems')
+    cursor = page['first_measure']
+    for system in systems:
+      a, count = system_range(system)
+      if a != cursor:
+        raise ValueError('system gap or overlap')
+      cursor += count
+      canonical.append(system)
+    if cursor != page['first_measure'] + page['measure_count']:
+      raise ValueError('systems disagree with page coverage')
+  if not isinstance(playback_pages, list) or len(playback_pages) != len(canonical):
+    raise ValueError('missing playback pages; regenerate score assets')
+  for i, page in enumerate(playback_pages):
+    expected = canonical[i:i + 2]
+    systems = page.get('systems', [])
+    if len(systems) != len(expected):
+      raise ValueError('invalid playback systems')
+    for actual, source in zip(systems, expected):
+      system_range(actual)
+      if any(actual[k] != source[k] for k in ('first_measure', 'measure_count', 'start_beat', 'end_beat')):
+        raise ValueError('playback changes system boundaries')
+    if any(page[k] != expected[0][k] for k in ('first_measure', 'start_beat')) or page['end_beat'] != expected[-1]['end_beat'] or page['measure_count'] != sum(s['measure_count'] for s in expected):
+      raise ValueError('invalid playback page timing')
 
 def validate_pages(document, pages):
   times = boundaries(document)

generator/score.py

@@ -24,10 +24,10 @@ def validate_json(document: dict, path: pathlib.Path, validated_pages: set[str]
       raise ValueError('invalid score bundle; regenerate score assets')
     if (presentation.get('engine'), presentation.get('width'), presentation.get('height')) != (generator.engraving.validation.ENGINE_NAME, generator.engraving.validation.PAGE_WIDTH, generator.engraving.validation.PAGE_HEIGHT):
       raise ValueError('unsupported score presentation; regenerate score assets')
-    generator.performance.validate_pages(document['music'], presentation['pages'])
+    generator.performance.validate_views(document['music'], presentation['pages'], presentation.get('playback_pages'))
     if document.get('performance') != generator.performance.timing(document['music']):
       raise ValueError('invalid performance timing')
-    for page in presentation['pages']:
+    for page in presentation['pages'] + presentation['playback_pages']:
       if not isinstance(page, dict) or not isinstance(page.get('path'), str) or not isinstance(page.get('sha256'), str):
         raise ValueError('invalid score page manifest')
       name = page['path']