Behdad Esfahbod f97b802869 [CFF] Minor
2018-11-29 14:20:45 -05:00

670 lines
21 KiB
Python

from fontTools.misc import psCharStrings
from fontTools import ttLib
from fontTools.pens.basePen import NullPen
from fontTools.pens.boundsPen import BoundsPen
from fontTools.misc.fixedTools import otRound
from fontTools.varLib.varStore import VarStoreInstancer
def _add_method(*clazzes):
"""Returns a decorator function that adds a new method to one or
more classes."""
def wrapper(method):
done = []
for clazz in clazzes:
if clazz in done: continue # Support multiple names of a clazz
done.append(clazz)
assert clazz.__name__ != 'DefaultTable', \
'Oops, table class not found.'
assert not hasattr(clazz, method.__name__), \
"Oops, class '%s' has method '%s'." % (clazz.__name__,
method.__name__)
setattr(clazz, method.__name__, method)
return None
return wrapper
def _uniq_sort(l):
return sorted(set(l))
class _ClosureGlyphsT2Decompiler(psCharStrings.SimpleT2Decompiler):
def __init__(self, components, localSubrs, globalSubrs):
psCharStrings.SimpleT2Decompiler.__init__(self,
localSubrs,
globalSubrs)
self.components = components
def op_endchar(self, index):
args = self.popall()
if len(args) >= 4:
from fontTools.encodings.StandardEncoding import StandardEncoding
# endchar can do seac accent bulding; The T2 spec says it's deprecated,
# but recent software that shall remain nameless does output it.
adx, ady, bchar, achar = args[-4:]
baseGlyph = StandardEncoding[bchar]
accentGlyph = StandardEncoding[achar]
self.components.add(baseGlyph)
self.components.add(accentGlyph)
@_add_method(ttLib.getTableClass('CFF '))
def closure_glyphs(self, s):
cff = self.cff
assert len(cff) == 1
font = cff[cff.keys()[0]]
glyphSet = font.CharStrings
decompose = s.glyphs
while decompose:
components = set()
for g in decompose:
if g not in glyphSet:
continue
gl = glyphSet[g]
subrs = getattr(gl.private, "Subrs", [])
decompiler = _ClosureGlyphsT2Decompiler(components, subrs, gl.globalSubrs)
decompiler.execute(gl)
components -= s.glyphs
s.glyphs.update(components)
decompose = components
@_add_method(ttLib.getTableClass('CFF '))
def prune_pre_subset(self, font, options):
cff = self.cff
# CFF table must have one font only
cff.fontNames = cff.fontNames[:1]
if options.notdef_glyph and not options.notdef_outline:
for fontname in cff.keys():
font = cff[fontname]
c, fdSelectIndex = font.CharStrings.getItemAndSelector('.notdef')
if hasattr(font, 'FDArray') and font.FDArray is not None:
private = font.FDArray[fdSelectIndex].Private
else:
private = font.Private
dfltWdX = private.defaultWidthX
nmnlWdX = private.nominalWidthX
pen = NullPen()
c.draw(pen) # this will set the charstring's width
if c.width != dfltWdX:
c.program = [c.width - nmnlWdX, 'endchar']
else:
c.program = ['endchar']
# Clear useless Encoding
for fontname in cff.keys():
font = cff[fontname]
# https://github.com/behdad/fonttools/issues/620
font.Encoding = "StandardEncoding"
return True # bool(cff.fontNames)
@_add_method(ttLib.getTableClass('CFF '))
def subset_glyphs(self, s):
cff = self.cff
for fontname in cff.keys():
font = cff[fontname]
cs = font.CharStrings
# Load all glyphs
for g in font.charset:
if g not in s.glyphs: continue
c, _ = cs.getItemAndSelector(g)
if cs.charStringsAreIndexed:
indices = [i for i,g in enumerate(font.charset) if g in s.glyphs]
csi = cs.charStringsIndex
csi.items = [csi.items[i] for i in indices]
del csi.file, csi.offsets
if hasattr(font, "FDSelect"):
sel = font.FDSelect
# XXX We want to set sel.format to None, such that the
# most compact format is selected. However, OTS was
# broken and couldn't parse a FDSelect format 0 that
# happened before CharStrings. As such, always force
# format 3 until we fix cffLib to always generate
# FDSelect after CharStrings.
# https://github.com/khaledhosny/ots/pull/31
#sel.format = None
sel.format = 3
sel.gidArray = [sel.gidArray[i] for i in indices]
cs.charStrings = {g:indices.index(v)
for g,v in cs.charStrings.items()
if g in s.glyphs}
else:
cs.charStrings = {g:v
for g,v in cs.charStrings.items()
if g in s.glyphs}
font.charset = [g for g in font.charset if g in s.glyphs]
font.numGlyphs = len(font.charset)
return True # any(cff[fontname].numGlyphs for fontname in cff.keys())
@_add_method(psCharStrings.T2CharString)
def subset_subroutines(self, subrs, gsubrs):
p = self.program
assert len(p)
for i in range(1, len(p)):
if p[i] == 'callsubr':
assert isinstance(p[i-1], int)
p[i-1] = subrs._used.index(p[i-1] + subrs._old_bias) - subrs._new_bias
elif p[i] == 'callgsubr':
assert isinstance(p[i-1], int)
p[i-1] = gsubrs._used.index(p[i-1] + gsubrs._old_bias) - gsubrs._new_bias
@_add_method(psCharStrings.T2CharString)
def drop_hints(self):
hints = self._hints
if hints.deletions:
p = self.program
for idx in reversed(hints.deletions):
del p[idx-2:idx]
if hints.has_hint:
assert not hints.deletions or hints.last_hint <= hints.deletions[0]
self.program = self.program[hints.last_hint:]
if not self.program:
# TODO CFF2 no need for endchar.
self.program.append('endchar')
if hasattr(self, 'width'):
# Insert width back if needed
if self.width != self.private.defaultWidthX:
self.program.insert(0, self.width - self.private.nominalWidthX)
if hints.has_hintmask:
i = 0
p = self.program
while i < len(p):
if p[i] in ['hintmask', 'cntrmask']:
assert i + 1 <= len(p)
del p[i:i+2]
continue
i += 1
assert len(self.program)
del self._hints
class _MarkingT2Decompiler(psCharStrings.SimpleT2Decompiler):
def __init__(self, localSubrs, globalSubrs):
psCharStrings.SimpleT2Decompiler.__init__(self,
localSubrs,
globalSubrs)
for subrs in [localSubrs, globalSubrs]:
if subrs and not hasattr(subrs, "_used"):
subrs._used = set()
def op_callsubr(self, index):
self.localSubrs._used.add(self.operandStack[-1]+self.localBias)
psCharStrings.SimpleT2Decompiler.op_callsubr(self, index)
def op_callgsubr(self, index):
self.globalSubrs._used.add(self.operandStack[-1]+self.globalBias)
psCharStrings.SimpleT2Decompiler.op_callgsubr(self, index)
class _DehintingT2Decompiler(psCharStrings.T2WidthExtractor):
class Hints(object):
def __init__(self):
# Whether calling this charstring produces any hint stems
# Note that if a charstring starts with hintmask, it will
# have has_hint set to True, because it *might* produce an
# implicit vstem if called under certain conditions.
self.has_hint = False
# Index to start at to drop all hints
self.last_hint = 0
# Index up to which we know more hints are possible.
# Only relevant if status is 0 or 1.
self.last_checked = 0
# The status means:
# 0: after dropping hints, this charstring is empty
# 1: after dropping hints, there may be more hints
# continuing after this, or there might be
# other things. Not clear yet.
# 2: no more hints possible after this charstring
self.status = 0
# Has hintmask instructions; not recursive
self.has_hintmask = False
# List of indices of calls to empty subroutines to remove.
self.deletions = []
pass
def __init__(self, css, localSubrs, globalSubrs, nominalWidthX, defaultWidthX):
self._css = css
psCharStrings.T2WidthExtractor.__init__(
self, localSubrs, globalSubrs, nominalWidthX, defaultWidthX)
def execute(self, charString):
old_hints = charString._hints if hasattr(charString, '_hints') else None
charString._hints = self.Hints()
psCharStrings.T2WidthExtractor.execute(self, charString)
hints = charString._hints
if hints.has_hint or hints.has_hintmask:
self._css.add(charString)
if hints.status != 2:
# Check from last_check, make sure we didn't have any operators.
for i in range(hints.last_checked, len(charString.program) - 1):
if isinstance(charString.program[i], str):
hints.status = 2
break
else:
hints.status = 1 # There's *something* here
hints.last_checked = len(charString.program)
if old_hints:
assert hints.__dict__ == old_hints.__dict__
def op_callsubr(self, index):
subr = self.localSubrs[self.operandStack[-1]+self.localBias]
psCharStrings.T2WidthExtractor.op_callsubr(self, index)
self.processSubr(index, subr)
def op_callgsubr(self, index):
subr = self.globalSubrs[self.operandStack[-1]+self.globalBias]
psCharStrings.T2WidthExtractor.op_callgsubr(self, index)
self.processSubr(index, subr)
def op_hstem(self, index):
psCharStrings.T2WidthExtractor.op_hstem(self, index)
self.processHint(index)
def op_vstem(self, index):
psCharStrings.T2WidthExtractor.op_vstem(self, index)
self.processHint(index)
def op_hstemhm(self, index):
psCharStrings.T2WidthExtractor.op_hstemhm(self, index)
self.processHint(index)
def op_vstemhm(self, index):
psCharStrings.T2WidthExtractor.op_vstemhm(self, index)
self.processHint(index)
def op_hintmask(self, index):
rv = psCharStrings.T2WidthExtractor.op_hintmask(self, index)
self.processHintmask(index)
return rv
def op_cntrmask(self, index):
rv = psCharStrings.T2WidthExtractor.op_cntrmask(self, index)
self.processHintmask(index)
return rv
def processHintmask(self, index):
cs = self.callingStack[-1]
hints = cs._hints
hints.has_hintmask = True
if hints.status != 2:
# Check from last_check, see if we may be an implicit vstem
for i in range(hints.last_checked, index - 1):
if isinstance(cs.program[i], str):
hints.status = 2
break
else:
# We are an implicit vstem
hints.has_hint = True
hints.last_hint = index + 1
hints.status = 0
hints.last_checked = index + 1
def processHint(self, index):
cs = self.callingStack[-1]
hints = cs._hints
hints.has_hint = True
hints.last_hint = index
hints.last_checked = index
def processSubr(self, index, subr):
cs = self.callingStack[-1]
hints = cs._hints
subr_hints = subr._hints
# Check from last_check, make sure we didn't have
# any operators.
if hints.status != 2:
for i in range(hints.last_checked, index - 1):
if isinstance(cs.program[i], str):
hints.status = 2
break
hints.last_checked = index
if hints.status != 2:
if subr_hints.has_hint:
hints.has_hint = True
# Decide where to chop off from
if subr_hints.status == 0:
hints.last_hint = index
else:
hints.last_hint = index - 2 # Leave the subr call in
elif subr_hints.status == 0:
hints.deletions.append(index)
hints.status = max(hints.status, subr_hints.status)
class _DesubroutinizingT2Decompiler(psCharStrings.SimpleT2Decompiler):
def __init__(self, localSubrs, globalSubrs, private=None):
psCharStrings.SimpleT2Decompiler.__init__(self,
localSubrs,
globalSubrs, private)
def execute(self, charString):
if (hasattr(charString, '_desubroutinized') and
charString._desubroutinized):
return
charString._patches = []
psCharStrings.SimpleT2Decompiler.execute(self, charString)
desubroutinized = charString.program[:]
for idx,expansion in reversed (charString._patches):
assert idx >= 2
assert desubroutinized[idx - 1] in ['callsubr', 'callgsubr'], desubroutinized[idx - 1]
assert type(desubroutinized[idx - 2]) == int
if expansion[-1] == 'return':
expansion = expansion[:-1]
desubroutinized[idx-2:idx] = expansion
if not charString.isCFF2:
if 'endchar' in desubroutinized:
# Cut off after first endchar
desubroutinized = desubroutinized[:desubroutinized.index('endchar') + 1]
else:
if not len(desubroutinized) or desubroutinized[-1] != 'return':
desubroutinized.append('return')
charString._desubroutinized = desubroutinized
del charString._patches
def op_callsubr(self, index):
subr = self.localSubrs[self.operandStack[-1]+self.localBias]
psCharStrings.SimpleT2Decompiler.op_callsubr(self, index)
self.processSubr(index, subr)
def op_callgsubr(self, index):
subr = self.globalSubrs[self.operandStack[-1]+self.globalBias]
psCharStrings.SimpleT2Decompiler.op_callgsubr(self, index)
self.processSubr(index, subr)
def processSubr(self, index, subr):
cs = self.callingStack[-1]
cs._patches.append((index, subr._desubroutinized))
@_add_method(ttLib.getTableClass('CFF '))
def prune_post_subset(self, font, options):
cff = self.cff
for fontname in cff.keys():
font = cff[fontname]
cs = font.CharStrings
# Drop unused FontDictionaries
if hasattr(font, "FDSelect"):
sel = font.FDSelect
indices = _uniq_sort(sel.gidArray)
sel.gidArray = [indices.index (ss) for ss in sel.gidArray]
arr = font.FDArray
arr.items = [arr[i] for i in indices]
del arr.file, arr.offsets
# Desubroutinize if asked for
if options.desubroutinize:
for g in font.charset:
c, _ = cs.getItemAndSelector(g)
c.decompile()
subrs = getattr(c.private, "Subrs", [])
decompiler = _DesubroutinizingT2Decompiler(subrs, c.globalSubrs)
decompiler.execute(c)
c.program = c._desubroutinized
# Drop hints if not needed
if not options.hinting:
# This can be tricky, but doesn't have to. What we do is:
#
# - Run all used glyph charstrings and recurse into subroutines,
# - For each charstring (including subroutines), if it has any
# of the hint stem operators, we mark it as such.
# Upon returning, for each charstring we note all the
# subroutine calls it makes that (recursively) contain a stem,
# - Dropping hinting then consists of the following two ops:
# * Drop the piece of the program in each charstring before the
# last call to a stem op or a stem-calling subroutine,
# * Drop all hintmask operations.
# - It's trickier... A hintmask right after hints and a few numbers
# will act as an implicit vstemhm. As such, we track whether
# we have seen any non-hint operators so far and do the right
# thing, recursively... Good luck understanding that :(
css = set()
for g in font.charset:
c, _ = cs.getItemAndSelector(g)
c.decompile()
subrs = getattr(c.private, "Subrs", [])
decompiler = _DehintingT2Decompiler(css, subrs, c.globalSubrs,
c.private.nominalWidthX,
c.private.defaultWidthX)
decompiler.execute(c)
c.width = decompiler.width
for charstring in css:
charstring.drop_hints()
del css
# Drop font-wide hinting values
all_privs = []
if hasattr(font, 'FDSelect'):
all_privs.extend(fd.Private for fd in font.FDArray)
else:
all_privs.append(font.Private)
for priv in all_privs:
for k in ['BlueValues', 'OtherBlues',
'FamilyBlues', 'FamilyOtherBlues',
'BlueScale', 'BlueShift', 'BlueFuzz',
'StemSnapH', 'StemSnapV', 'StdHW', 'StdVW',
'ForceBold', 'LanguageGroup', 'ExpansionFactor']:
if hasattr(priv, k):
setattr(priv, k, None)
# Renumber subroutines to remove unused ones
# Mark all used subroutines
for g in font.charset:
c, _ = cs.getItemAndSelector(g)
subrs = getattr(c.private, "Subrs", [])
decompiler = _MarkingT2Decompiler(subrs, c.globalSubrs)
decompiler.execute(c)
all_subrs = [font.GlobalSubrs]
if hasattr(font, 'FDSelect'):
all_subrs.extend(fd.Private.Subrs for fd in font.FDArray if hasattr(fd.Private, 'Subrs') and fd.Private.Subrs)
elif hasattr(font.Private, 'Subrs') and font.Private.Subrs:
all_subrs.append(font.Private.Subrs)
subrs = set(subrs) # Remove duplicates
# Prepare
for subrs in all_subrs:
if not hasattr(subrs, '_used'):
subrs._used = set()
subrs._used = _uniq_sort(subrs._used)
subrs._old_bias = psCharStrings.calcSubrBias(subrs)
subrs._new_bias = psCharStrings.calcSubrBias(subrs._used)
# Renumber glyph charstrings
for g in font.charset:
c, _ = cs.getItemAndSelector(g)
subrs = getattr(c.private, "Subrs", [])
c.subset_subroutines (subrs, font.GlobalSubrs)
# Renumber subroutines themselves
for subrs in all_subrs:
if subrs == font.GlobalSubrs:
if not hasattr(font, 'FDSelect') and hasattr(font.Private, 'Subrs'):
local_subrs = font.Private.Subrs
else:
local_subrs = []
else:
local_subrs = subrs
subrs.items = [subrs.items[i] for i in subrs._used]
if hasattr(subrs, 'file'):
del subrs.file
if hasattr(subrs, 'offsets'):
del subrs.offsets
for subr in subrs.items:
subr.subset_subroutines (local_subrs, font.GlobalSubrs)
# Delete local SubrsIndex if empty
if hasattr(font, 'FDSelect'):
for fd in font.FDArray:
_delete_empty_subrs(fd.Private)
else:
_delete_empty_subrs(font.Private)
# Cleanup
for subrs in all_subrs:
del subrs._used, subrs._old_bias, subrs._new_bias
return True
def _delete_empty_subrs(private_dict):
if hasattr(private_dict, 'Subrs') and not private_dict.Subrs:
if 'Subrs' in private_dict.rawDict:
del private_dict.rawDict['Subrs']
del private_dict.Subrs
@_add_method(ttLib.getTableClass('CFF2'))
def desubroutinize(self, font):
cff = self.cff
for fontname in cff.keys():
font = cff[fontname]
cs = font.CharStrings
for g in font.charset:
c, _ = cs.getItemAndSelector(g)
c.decompile()
subrs = getattr(c.private, "Subrs", [])
decompiler = _DesubroutinizingT2Decompiler(subrs, c.globalSubrs, c.private)
decompiler.execute(c)
c.program = c._desubroutinized
# Delete All the Subrs!!!
if font.GlobalSubrs:
del font.GlobalSubrs
if hasattr(font, 'FDArray'):
for fd in font.FDArray:
pd = fd.Private
if hasattr(pd, 'Subrs'):
del pd.Subrs
if 'Subrs' in pd.rawDict:
del pd.rawDict['Subrs']
def interpolate_cff2_PrivateDict(topDict, interpolateFromDeltas):
pd_blend_lists = ("BlueValues", "OtherBlues", "FamilyBlues",
"FamilyOtherBlues", "StemSnapH",
"StemSnapV")
pd_blend_values = ("BlueScale", "BlueShift",
"BlueFuzz", "StdHW", "StdVW")
for fontDict in topDict.FDArray:
pd = fontDict.Private
vsindex = pd.vsindex if (hasattr(pd, 'vsindex')) else 0
for key, value in pd.rawDict.items():
if (key in pd_blend_values) and isinstance(value, list):
delta = interpolateFromDeltas(vsindex, value[1:])
pd.rawDict[key] = otRound(value[0] + delta)
elif (key in pd_blend_lists) and isinstance(value[0], list):
"""If any argument in a BlueValues list is a blend list,
then they all are. The first value of each list is an
absolute value. The delta tuples are calculated from
relative master values, hence we need to append all the
deltas to date to each successive absolute value."""
delta = 0
for i, val_list in enumerate(value):
delta += otRound(interpolateFromDeltas(vsindex,
val_list[1:]))
value[i] = val_list[0] + delta
def interpolate_cff2_charstrings(topDict, interpolateFromDeltas, glyphOrder):
charstrings = topDict.CharStrings
for gname in glyphOrder:
# Interpolate charstring
charstring = charstrings[gname]
pd = charstring.private
vsindex = pd.vsindex if (hasattr(pd, 'vsindex')) else 0
num_regions = pd.getNumRegions(vsindex)
numMasters = num_regions + 1
new_program = []
last_i = 0
for i, token in enumerate(charstring.program):
if token == 'blend':
num_args = charstring.program[i - 1]
""" The stack is now:
..args for following operations
num_args values from the default font
num_args tuples, each with numMasters-1 delta values
num_blend_args
'blend'
"""
argi = i - (num_args*numMasters + 1)
end_args = tuplei = argi + num_args
while argi < end_args:
next_ti = tuplei + num_regions
deltas = charstring.program[tuplei:next_ti]
delta = interpolateFromDeltas(vsindex, deltas)
charstring.program[argi] += otRound(delta)
tuplei = next_ti
argi += 1
new_program.extend(charstring.program[last_i:end_args])
last_i = i + 1
if last_i != 0:
new_program.extend(charstring.program[last_i:])
charstring.program = new_program
def interpolate_cff2_metrics(varfont, topDict, glyphOrder, loc):
"""Unlike TrueType glyphs, neither advance width nor bounding box
info is stored in a CFF2 charstring. The width data exists only in
the hmtx and HVAR tables. Since LSB data cannot be interpolated
reliably from the master LSB values in the hmtx table, we traverse
the charstring to determine the actual bound box. """
charstrings = topDict.CharStrings
boundsPen = BoundsPen(glyphOrder)
hmtx = varfont['hmtx']
hvar_table = None
if 'HVAR' in varfont:
hvar_table = varfont['HVAR'].table
fvar = varfont['fvar']
varStoreInstancer = VarStoreInstancer(hvar_table.VarStore, fvar.axes, loc)
for gid, gname in enumerate(glyphOrder):
entry = list(hmtx[gname])
# get width delta.
if hvar_table:
if hvar_table.AdvWidthMap:
width_idx = hvar_table.AdvWidthMap.mapping[gname]
else:
width_idx = gid
width_delta = otRound(varStoreInstancer[width_idx])
else:
width_delta = 0
# get LSB.
boundsPen.init()
charstring = charstrings[gname]
charstring.draw(boundsPen)
if boundsPen.bounds is None:
# Happens with non-marking glyphs
lsb_delta = 0
else:
lsb = boundsPen.bounds[0]
lsb_delta = entry[1] - lsb
if lsb_delta or width_delta:
if width_delta:
entry[0] += width_delta
if lsb_delta:
entry[1] = lsb
hmtx[gname] = tuple(entry)