blob: a087b2d3ebf45d30e26422c2fb31f1248b75892e [file] [log] [blame]
from __future__ import print_function, division, absolute_import
from collections import namedtuple
from fontTools import ttLib
from fontTools.ttLib.tables import otTables as ot
from fontTools.ttLib.tables.otBase import ValueRecord, valueRecordFormatDict
def buildCoverage(glyphs, glyphMap):
if not glyphs:
return None
self = ot.Coverage()
self.glyphs = sorted(glyphs, key=glyphMap.__getitem__)
return self
def buildLookup(subtables, flags=0, markFilterSet=None):
if subtables is None:
return None
subtables = [st for st in subtables if st is not None]
if not subtables:
return None
assert all(t.LookupType == subtables[0].LookupType for t in subtables), \
("all subtables must have the same LookupType; got %s" %
repr([t.LookupType for t in subtables]))
self = ot.Lookup()
self.LookupType = subtables[0].LookupType
self.LookupFlag = flags
self.SubTable = subtables
self.SubTableCount = len(self.SubTable)
if markFilterSet is not None:
assert self.LookupFlag & LOOKUP_FLAG_USE_MARK_FILTERING_SET, \
("if markFilterSet is not None, flags must set "
"LOOKUP_FLAG_USE_MARK_FILTERING_SET; flags=0x%04x" % flags)
assert isinstance(markFilterSet, int), markFilterSet
self.MarkFilteringSet = markFilterSet
assert (self.LookupFlag & LOOKUP_FLAG_USE_MARK_FILTERING_SET) == 0, \
("if markFilterSet is None, flags must not set "
"LOOKUP_FLAG_USE_MARK_FILTERING_SET; flags=0x%04x" % flags)
return self
def buildSingleSubstSubtable(mapping):
if not mapping:
return None
self = ot.SingleSubst()
self.mapping = dict(mapping)
return self
def buildMultipleSubstSubtable(mapping):
if not mapping:
return None
self = ot.MultipleSubst()
self.mapping = dict(mapping)
return self
def buildAlternateSubstSubtable(mapping):
if not mapping:
return None
self = ot.AlternateSubst()
self.alternates = dict(mapping)
return self
def _getLigatureKey(components):
"""Computes a key for ordering ligatures in a GSUB Type-4 lookup.
When building the OpenType lookup, we need to make sure that
the longest sequence of components is listed first, so we
use the negative length as the primary key for sorting.
To make buildLigatureSubstSubtable() deterministic, we use the
component sequence as the secondary key.
For example, this will sort (f,f,f) < (f,f,i) < (f,f) < (f,i) < (f,l).
return (-len(components), components)
def buildLigatureSubstSubtable(mapping):
if not mapping:
return None
self = ot.LigatureSubst()
# The following single line can replace the rest of this function
# with fontTools >= 3.1:
# self.ligatures = dict(mapping)
self.ligatures = {}
for components in sorted(mapping.keys(), key=_getLigatureKey):
ligature = ot.Ligature()
ligature.Component = components[1:]
ligature.CompCount = len(ligature.Component) + 1
ligature.LigGlyph = mapping[components]
firstGlyph = components[0]
self.ligatures.setdefault(firstGlyph, []).append(ligature)
return self
def buildAnchor(x, y, point=None, deviceX=None, deviceY=None):
self = ot.Anchor()
self.XCoordinate, self.YCoordinate = x, y
self.Format = 1
if point is not None:
self.AnchorPoint = point
self.Format = 2
if deviceX is not None or deviceY is not None:
assert self.Format == 1, \
"Either point, or both of deviceX/deviceY, must be None."
self.XDeviceTable = deviceX
self.YDeviceTable = deviceY
self.Format = 3
return self
def buildBaseArray(bases, numMarkClasses, glyphMap):
self = ot.BaseArray()
self.BaseRecord = []
for base in sorted(bases, key=glyphMap.__getitem__):
b = bases[base]
anchors = [b.get(markClass) for markClass in range(numMarkClasses)]
self.BaseCount = len(self.BaseRecord)
return self
def buildBaseRecord(anchors):
"""[otTables.Anchor, otTables.Anchor, ...] --> otTables.BaseRecord"""
self = ot.BaseRecord()
self.BaseAnchor = anchors
return self
def buildComponentRecord(anchors):
"""[otTables.Anchor, otTables.Anchor, ...] --> otTables.ComponentRecord"""
if not anchors:
return None
self = ot.ComponentRecord()
self.LigatureAnchor = anchors
return self
def buildCursivePosSubtable(attach, glyphMap):
"""{"alef": (entry, exit)} --> otTables.CursivePos"""
if not attach:
return None
self = ot.CursivePos()
self.Format = 1
self.Coverage = buildCoverage(attach.keys(), glyphMap)
self.EntryExitRecord = []
for glyph in self.Coverage.glyphs:
entryAnchor, exitAnchor = attach[glyph]
rec = ot.EntryExitRecord()
rec.EntryAnchor = entryAnchor
rec.ExitAnchor = exitAnchor
self.EntryExitCount = len(self.EntryExitRecord)
return self
def buildDevice(deltas):
"""{8:+1, 10:-3, ...} --> otTables.Device"""
if not deltas:
return None
self = ot.Device()
keys = deltas.keys()
self.StartSize = startSize = min(keys)
self.EndSize = endSize = max(keys)
assert 0 <= startSize <= endSize
self.DeltaValue = deltaValues = [
deltas.get(size, 0)
for size in range(startSize, endSize + 1)]
maxDelta = max(deltaValues)
minDelta = min(deltaValues)
assert minDelta > -129 and maxDelta < 128
if minDelta > -3 and maxDelta < 2:
self.DeltaFormat = 1
elif minDelta > -9 and maxDelta < 8:
self.DeltaFormat = 2
self.DeltaFormat = 3
return self
def buildLigatureArray(ligs, numMarkClasses, glyphMap):
self = ot.LigatureArray()
self.LigatureAttach = []
for lig in sorted(ligs, key=glyphMap.__getitem__):
anchors = []
for component in ligs[lig]:
anchors.append([component.get(mc) for mc in range(numMarkClasses)])
self.LigatureCount = len(self.LigatureAttach)
return self
def buildLigatureAttach(components):
"""[[Anchor, Anchor], [Anchor, Anchor, Anchor]] --> LigatureAttach"""
self = ot.LigatureAttach()
self.ComponentRecord = [buildComponentRecord(c) for c in components]
self.ComponentCount = len(self.ComponentRecord)
return self
def buildMarkArray(marks, glyphMap):
"""{"acute": (markClass, otTables.Anchor)} --> otTables.MarkArray"""
self = ot.MarkArray()
self.MarkRecord = []
for mark in sorted(marks.keys(), key=glyphMap.__getitem__):
markClass, anchor = marks[mark]
markrec = buildMarkRecord(markClass, anchor)
self.MarkCount = len(self.MarkRecord)
return self
def buildMarkBasePos(marks, bases, glyphMap):
"""Build a list of MarkBasePos subtables.
a1, a2, a3, a4, a5 = buildAnchor(500, 100), ...
marks = {"acute": (0, a1), "grave": (0, a1), "cedilla": (1, a2)}
bases = {"a": {0: a3, 1: a5}, "b": {0: a4, 1: a5}}
# TODO: Consider emitting multiple subtables to save space.
# Partition the marks and bases into disjoint subsets, so that
# MarkBasePos rules would only access glyphs from a single
# subset. This would likely lead to smaller mark/base
# matrices, so we might be able to omit many of the empty
# anchor tables that we currently produce. Of course, this
# would only work if the MarkBasePos rules of real-world fonts
# allow partitioning into multiple subsets. We should find out
# whether this is the case; if so, implement the optimization.
# On the other hand, a very large number of subtables could
# slow down layout engines; so this would need profiling.
return [buildMarkBasePosSubtable(marks, bases, glyphMap)]
def buildMarkBasePosSubtable(marks, bases, glyphMap):
"""Build a single MarkBasePos subtable.
a1, a2, a3, a4, a5 = buildAnchor(500, 100), ...
marks = {"acute": (0, a1), "grave": (0, a1), "cedilla": (1, a2)}
bases = {"a": {0: a3, 1: a5}, "b": {0: a4, 1: a5}}
self = ot.MarkBasePos()
self.Format = 1
self.MarkCoverage = buildCoverage(marks, glyphMap)
self.MarkArray = buildMarkArray(marks, glyphMap)
self.ClassCount = max([mc for mc, _ in marks.values()]) + 1
self.BaseCoverage = buildCoverage(bases, glyphMap)
self.BaseArray = buildBaseArray(bases, self.ClassCount, glyphMap)
return self
def buildMarkLigPos(marks, ligs, glyphMap):
"""Build a list of MarkLigPos subtables.
a1, a2, a3, a4, a5 = buildAnchor(500, 100), ...
marks = {"acute": (0, a1), "grave": (0, a1), "cedilla": (1, a2)}
ligs = {"f_i": [{0: a3, 1: a5}, {0: a4, 1: a5}], "c_t": [{...}, {...}]}
# TODO: Consider splitting into multiple subtables to save space,
# as with MarkBasePos, this would be a trade-off that would need
# profiling. And, depending on how typical fonts are structured,
# it might not be worth doing at all.
return [buildMarkLigPosSubtable(marks, ligs, glyphMap)]
def buildMarkLigPosSubtable(marks, ligs, glyphMap):
"""Build a single MarkLigPos subtable.
a1, a2, a3, a4, a5 = buildAnchor(500, 100), ...
marks = {"acute": (0, a1), "grave": (0, a1), "cedilla": (1, a2)}
ligs = {"f_i": [{0: a3, 1: a5}, {0: a4, 1: a5}], "c_t": [{...}, {...}]}
self = ot.MarkLigPos()
self.Format = 1
self.MarkCoverage = buildCoverage(marks, glyphMap)
self.MarkArray = buildMarkArray(marks, glyphMap)
self.ClassCount = max([mc for mc, _ in marks.values()]) + 1
self.LigatureCoverage = buildCoverage(ligs, glyphMap)
self.LigatureArray = buildLigatureArray(ligs, self.ClassCount, glyphMap)
return self
def buildMarkRecord(classID, anchor):
assert isinstance(classID, int)
assert isinstance(anchor, ot.Anchor)
self = ot.MarkRecord()
self.Class = classID
self.MarkAnchor = anchor
return self
def buildMark2Record(anchors):
"""[otTables.Anchor, otTables.Anchor, ...] --> otTables.Mark2Record"""
self = ot.Mark2Record()
self.Mark2Anchor = anchors
return self
def _getValueFormat(f, values, i):
"""Helper for buildPairPos{Glyphs|Classes}Subtable."""
if f is not None:
return f
mask = 0
for value in values:
if value is not None and value[i] is not None:
mask |= value[i].getFormat()
return mask
def buildPairPosClassesSubtable(pairs, glyphMap,
valueFormat1=None, valueFormat2=None):
coverage = set()
classDef1 = ClassDefBuilder(useClass0=True)
classDef2 = ClassDefBuilder(useClass0=False)
for gc1, gc2 in sorted(pairs):
self = ot.PairPos()
self.Format = 2
self.ValueFormat1 = _getValueFormat(valueFormat1, pairs.values(), 0)
self.ValueFormat2 = _getValueFormat(valueFormat2, pairs.values(), 1)
self.Coverage = buildCoverage(coverage, glyphMap)
self.ClassDef1 =
self.ClassDef2 =
classes1 = classDef1.classes()
classes2 = classDef2.classes()
self.Class1Record = []
for c1 in classes1:
rec1 = ot.Class1Record()
rec1.Class2Record = []
for c2 in classes2:
rec2 = ot.Class2Record()
rec2.Value1, rec2.Value2 = pairs.get((c1, c2), (None, None))
self.Class1Count = len(self.Class1Record)
self.Class2Count = len(classes2)
return self
def buildPairPosGlyphs(pairs, glyphMap):
p = {} # (formatA, formatB) --> {(glyphA, glyphB): (valA, valB)}
for (glyphA, glyphB), (valA, valB) in pairs.items():
formatA = valA.getFormat() if valA is not None else 0
formatB = valB.getFormat() if valB is not None else 0
pos = p.setdefault((formatA, formatB), {})
pos[(glyphA, glyphB)] = (valA, valB)
return [
buildPairPosGlyphsSubtable(pos, glyphMap, formatA, formatB)
for ((formatA, formatB), pos) in sorted(p.items())]
def buildPairPosGlyphsSubtable(pairs, glyphMap,
valueFormat1=None, valueFormat2=None):
self = ot.PairPos()
self.Format = 1
self.ValueFormat1 = _getValueFormat(valueFormat1, pairs.values(), 0)
self.ValueFormat2 = _getValueFormat(valueFormat2, pairs.values(), 1)
p = {}
for (glyphA, glyphB), (valA, valB) in pairs.items():
p.setdefault(glyphA, []).append((glyphB, valA, valB))
self.Coverage = buildCoverage({g for g, _ in pairs.keys()}, glyphMap)
self.PairSet = []
for glyph in self.Coverage.glyphs:
ps = ot.PairSet()
ps.PairValueRecord = []
for glyph2, val1, val2 in \
sorted(p[glyph], key=lambda x: glyphMap[x[0]]):
pvr = ot.PairValueRecord()
pvr.SecondGlyph = glyph2
pvr.Value1 = val1 if val1 and val1.getFormat() != 0 else None
pvr.Value2 = val2 if val2 and val2.getFormat() != 0 else None
ps.PairValueCount = len(ps.PairValueRecord)
self.PairSetCount = len(self.PairSet)
return self
def buildSinglePos(mapping, glyphMap):
"""{"glyph": ValueRecord} --> [otTables.SinglePos*]"""
result, handled = [], set()
# In SinglePos format 1, the covered glyphs all share the same ValueRecord.
# In format 2, each glyph has its own ValueRecord, but these records
# all have the same properties (eg., all have an X but no Y placement).
coverages, masks, values = {}, {}, {}
for glyph, value in mapping.items():
key = _getSinglePosValueKey(value)
coverages.setdefault(key, []).append(glyph)
masks.setdefault(key[0], []).append(key)
values[key] = value
# If a ValueRecord is shared between multiple glyphs, we generate
# a SinglePos format 1 subtable; that is the most compact form.
for key, glyphs in coverages.items():
# 5 ushorts is the length of introducing another sublookup
if len(glyphs) * _getSinglePosValueSize(key) > 5:
format1Mapping = {g: values[key] for g in glyphs}
result.append(buildSinglePosSubtable(format1Mapping, glyphMap))
# In the remaining ValueRecords, look for those whose valueFormat
# (the set of used properties) is shared between multiple records.
# These will get encoded in format 2.
for valueFormat, keys in masks.items():
f2 = [k for k in keys if k not in handled]
if len(f2) > 1:
format2Mapping = {}
for k in f2:
format2Mapping.update((g, values[k]) for g in coverages[k])
result.append(buildSinglePosSubtable(format2Mapping, glyphMap))
# The remaining ValueRecords are only used by a few glyphs, normally
# one. We encode these in format 1 again.
for key, glyphs in coverages.items():
if key not in handled:
for g in glyphs:
st = buildSinglePosSubtable({g: values[key]}, glyphMap)
# When the OpenType layout engine traverses the subtables, it will
# stop after the first matching subtable. Therefore, we sort the
# resulting subtables by decreasing coverage size; this increases
# the chance that the layout engine can do an early exit. (Of course,
# this would only be true if all glyphs were equally frequent, which
# is not really the case; but we do not know their distribution).
# If two subtables cover the same number of glyphs, we sort them
# by glyph ID so that our output is deterministic.
result.sort(key=lambda t: _getSinglePosTableKey(t, glyphMap))
return result
def buildSinglePosSubtable(values, glyphMap):
"""{glyphName: otBase.ValueRecord} --> otTables.SinglePos"""
self = ot.SinglePos()
self.Coverage = buildCoverage(values.keys(), glyphMap)
valueRecords = [values[g] for g in self.Coverage.glyphs]
self.ValueFormat = 0
for v in valueRecords:
self.ValueFormat |= v.getFormat()
if all(v == valueRecords[0] for v in valueRecords):
self.Format = 1
if self.ValueFormat != 0:
self.Value = valueRecords[0]
self.Value = None
self.Format = 2
self.Value = valueRecords
self.ValueCount = len(self.Value)
return self
def _getSinglePosTableKey(subtable, glyphMap):
assert isinstance(subtable, ot.SinglePos), subtable
glyphs = subtable.Coverage.glyphs
return (-len(glyphs), glyphMap[glyphs[0]])
def _getSinglePosValueKey(valueRecord):
"""otBase.ValueRecord --> (2, ("YPlacement": 12))"""
assert isinstance(valueRecord, ValueRecord), valueRecord
valueFormat, result = 0, []
for name, value in valueRecord.__dict__.items():
if isinstance(value, ot.Device):
result.append((name, _makeDeviceTuple(value)))
result.append((name, value))
valueFormat |= valueRecordFormatDict[name][0]
result.insert(0, valueFormat)
return tuple(result)
_DeviceTuple = namedtuple("_DeviceTuple", "DeltaFormat StartSize EndSize DeltaValue")
def _makeDeviceTuple(device):
"""otTables.Device --> tuple, for making device tables unique"""
return _DeviceTuple(
() if device.DeltaFormat & 0x8000 else tuple(device.DeltaValue)
def _getSinglePosValueSize(valueKey):
"""Returns how many ushorts this valueKey (short form of ValueRecord) takes up"""
count = 0
for _, v in valueKey[1:]:
if isinstance(v, _DeviceTuple):
count += len(v.DeltaValue) + 3
count += 1
return count
def buildValue(value):
self = ValueRecord()
for k, v in value.items():
setattr(self, k, v)
return self
def buildAttachList(attachPoints, glyphMap):
"""{"glyphName": [4, 23]} --> otTables.AttachList, or None"""
if not attachPoints:
return None
self = ot.AttachList()
self.Coverage = buildCoverage(attachPoints.keys(), glyphMap)
self.AttachPoint = [buildAttachPoint(attachPoints[g])
for g in self.Coverage.glyphs]
self.GlyphCount = len(self.AttachPoint)
return self
def buildAttachPoint(points):
"""[4, 23, 41] --> otTables.AttachPoint"""
if not points:
return None
self = ot.AttachPoint()
self.PointIndex = sorted(set(points))
self.PointCount = len(self.PointIndex)
return self
def buildCaretValueForCoord(coord):
"""500 --> otTables.CaretValue, format 1"""
self = ot.CaretValue()
self.Format = 1
self.Coordinate = coord
return self
def buildCaretValueForPoint(point):
"""4 --> otTables.CaretValue, format 2"""
self = ot.CaretValue()
self.Format = 2
self.CaretValuePoint = point
return self
def buildLigCaretList(coords, points, glyphMap):
"""{"f_f_i":[300,600]}, {"c_t":[28]} --> otTables.LigCaretList, or None"""
glyphs = set(coords.keys()) if coords else set()
if points:
carets = {g: buildLigGlyph(coords.get(g), points.get(g)) for g in glyphs}
carets = {g: c for g, c in carets.items() if c is not None}
if not carets:
return None
self = ot.LigCaretList()
self.Coverage = buildCoverage(carets.keys(), glyphMap)
self.LigGlyph = [carets[g] for g in self.Coverage.glyphs]
self.LigGlyphCount = len(self.LigGlyph)
return self
def buildLigGlyph(coords, points):
"""([500], [4]) --> otTables.LigGlyph; None for empty coords/points"""
carets = []
if coords:
carets.extend([buildCaretValueForCoord(c) for c in sorted(coords)])
if points:
carets.extend([buildCaretValueForPoint(p) for p in sorted(points)])
if not carets:
return None
self = ot.LigGlyph()
self.CaretValue = carets
self.CaretCount = len(self.CaretValue)
return self
def buildMarkGlyphSetsDef(markSets, glyphMap):
"""[{"acute","grave"}, {"caron","grave"}] --> otTables.MarkGlyphSetsDef"""
if not markSets:
return None
self = ot.MarkGlyphSetsDef()
self.MarkSetTableFormat = 1
self.Coverage = [buildCoverage(m, glyphMap) for m in markSets]
self.MarkSetCount = len(self.Coverage)
return self
class ClassDefBuilder(object):
"""Helper for building ClassDef tables."""
def __init__(self, useClass0):
self.classes_ = set()
self.glyphs_ = {}
self.useClass0_ = useClass0
def canAdd(self, glyphs):
if isinstance(glyphs, (set, frozenset)):
glyphs = sorted(glyphs)
glyphs = tuple(glyphs)
if glyphs in self.classes_:
return True
for glyph in glyphs:
if glyph in self.glyphs_:
return False
return True
def add(self, glyphs):
if isinstance(glyphs, (set, frozenset)):
glyphs = sorted(glyphs)
glyphs = tuple(glyphs)
if glyphs in self.classes_:
for glyph in glyphs:
assert glyph not in self.glyphs_
self.glyphs_[glyph] = glyphs
def classes(self):
# In ClassDef1 tables, class id #0 does not need to be encoded
# because zero is the default. Therefore, we use id #0 for the
# glyph class that has the largest number of members. However,
# in other tables than ClassDef1, 0 means "every other glyph"
# so we should not use that ID for any real glyph classes;
# we implement this by inserting an empty set at position 0.
# TODO: Instead of counting the number of glyphs in each class,
# we should determine the encoded size. If the glyphs in a large
# class form a contiguous range, the encoding is actually quite
# compact, whereas a non-contiguous set might need a lot of bytes
# in the output file. We don't get this right with the key below.
result = sorted(self.classes_, key=lambda s: (len(s), s), reverse=True)
if not self.useClass0_:
result.insert(0, frozenset())
return result
def build(self):
glyphClasses = {}
for classID, glyphs in enumerate(self.classes()):
if classID == 0:
for glyph in glyphs:
glyphClasses[glyph] = classID
classDef = ot.ClassDef()
classDef.classDefs = glyphClasses
return classDef