Sizing

generator/engraving/layout.py

@@ -54,9 +54,6 @@ def column(index: generator.engraving.notation.ScoreIndex, time: fractions.Fract
   for owner, _, item in index.harmonies_by_onset.get(time, []):
     if owner is measure:
       items.append(fonts.text(generator.harmony.symbol(item), 0, 0, 18 if index.staff.get('tablature') else 21, 'harmony', (item['id'],)))
-  for owner, i, value in index.tempos_by_onset.get(time, []):
-    if owner is measure:
-      items.extend(generator.engraving.attributes.tempo(value, fonts, 0, 0, style.space, measure['id'] + f':tempo:{i}'))
   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'):
@@ -159,54 +156,84 @@ def make_system(index: generator.engraving.notation.ScoreIndex, start: fractions
   items = generator.engraving.tablature.staff(index, items + tab_items, start, end, content_left, width - 1, fonts, style)
   return generator.engraving.types.System(start, end, tuple(items), tuple(anchors), tuple(fragments), generator.engraving.types.bounds(items))
 
-def fit_page_systems(systems, index, row_height, fonts, style):
-  scale = min(1, row_height / max(s.box.bottom - s.box.top for s in systems))
+def fit_part_systems(systems, index, available_height, fonts, style):
+
+  def fitting_scale(items):
+    scale = 1
+    for first in range(0, len(items), 2):
+      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)
+    return scale
+
+  scale = fitting_scale(systems)
   columns = collections.OrderedDict()
-  # Re-space columns at the final physical width; scale glyphs uniformly, not horizontally.
+  # Fit the entire part together; only spacing, never page-specific glyph sizes, varies.
   for _ in range(8):
     width = (style.width - 2 * style.margin_x - 2) / scale
     fitted = [make_system(index, s.start, s.end, fonts, style, justify=s.end < index.end, columns=columns, staff_width=width) for s in systems]
-    height = max(s.box.bottom - s.box.top for s in fitted)
-    if height * scale <= row_height + 0.001:
+    next_scale = fitting_scale(fitted)
+    if scale <= next_scale + 0.000001:
       return [s.scaled(scale) for s in fitted]
-    scale = row_height / height
-  raise generator.engraving.types.EngravingError(f'at musical offset {systems[0].start}: page spacing did not converge')
+    scale = next_scale
+  raise generator.engraving.types.EngravingError('part spacing did not converge')
+
+def part_header(document, fonts, style):
+  size = 16
+  title = document['metadata']['title']
+  item = fonts.text(title, style.margin_x, style.margin_y + size, size, 'title', ())
+  while item.box.right > style.width - style.margin_x and size > 12:
+    size -= 1
+    item = fonts.text(title, style.margin_x, style.margin_y + size, size, 'title', ())
+  if item.box.right > style.width - style.margin_x:
+    raise generator.engraving.types.EngravingError('score title cannot fit the page without clipping')
+  result = [item]
+  subtitle = ' - '.join(str(value) for value in (document['metadata'].get('composer'), document['staves'][0].get('name')) if value)
+  if not subtitle:
+    return result
+  credit = fonts.text(subtitle, 0, style.margin_y + size, 12, 'subtitle', ())
+  width = credit.box.right - credit.box.left
+  if item.box.right + 20 + width <= style.width - style.margin_x:
+    result.append(credit.moved(style.width - style.margin_x - credit.box.right, 0))
+    return result
+  line = ''
+  baseline = item.box.bottom + 15
+  for word in subtitle.split():
+    text = ' '.join(filter(None, (line, word)))
+    candidate = fonts.text(text, style.margin_x, baseline, 12, 'subtitle', ())
+    if candidate.box.right > style.width - style.margin_x and line:
+      result.append(fonts.text(line, style.margin_x, baseline, 12, 'subtitle', ()))
+      baseline = result[-1].box.bottom + 15
+      text = word
+      candidate = fonts.text(text, style.margin_x, baseline, 12, 'subtitle', ())
+    if candidate.box.right > style.width - style.margin_x:
+      raise generator.engraving.types.EngravingError('score credits cannot fit the page without clipping')
+    line = text
+  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 = []
   index = index or generator.engraving.notation.ScoreIndex(document)
-  guitar = document['staves'][0].get('tablature', False)
-  header_gap = 14 if guitar else 24
-
-  def page_header(number):
-    title = document['metadata']['title']
-    size = (20 if number == 1 else 16) if guitar else (26 if number == 1 else 17)
-    item = fonts.text(title, style.margin_x, style.margin_y + size, size, 'title', ())
-    while item.box.right > style.width - style.margin_x and size > 12:
-      size -= 1
-      item = fonts.text(title, style.margin_x, style.margin_y + size, size, 'title', ())
-    if item.box.right > style.width - style.margin_x:
-      raise generator.engraving.types.EngravingError('score title cannot fit the page without clipping')
-    result = [item]
-    if number == 1:
-      subtitle = ' - '.join(str(value) for value in (document['metadata'].get('composer'), document['staves'][0].get('name')) if value)
-      if subtitle:
-        result.append(fonts.text(subtitle, style.margin_x, item.box.bottom + (15 if guitar else 22), 12 if guitar else 16, 'subtitle', ()))
-    return result
-
+  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)]
+  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
-    header = page_header(number)
-    top = generator.engraving.types.bounds(header).bottom + header_gap
-    row_height = (style.height - style.margin_y - 24 - top - style.system_gap) / 2
-    if row_height <= 0:
-      raise generator.engraving.types.EngravingError('page header leaves no room for two music systems')
-    pair = fit_page_systems(systems[first:first + 2], index, row_height, fonts, style)
+    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 row, system in enumerate(pair):
-      dx, dy = style.margin_x + 1, top + row * (row_height + style.system_gap) - system.box.top
+    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)))
-    footer = fonts.text(str(number), style.width / 2, style.height - style.margin_y, 12, 'page-number', (), True)
+      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)