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from fontTools.misc import xmlWriter
from fontTools.misc.textTools import Tag, byteord, tostr
from fontTools.misc.loggingTools import deprecateArgument
from fontTools.ttLib import TTLibError
from fontTools.ttLib.sfnt import SFNTReader, SFNTWriter
from io import BytesIO, StringIO
import os
import logging
import traceback
log = logging.getLogger(__name__)
class TTFont(object):
"""Represents a TrueType font.
The object manages file input and output, and offers a convenient way of
accessing tables. Tables will be only decompiled when necessary, ie. when
they're actually accessed. This means that simple operations can be extremely fast.
Example usage::
>> from fontTools import ttLib
>> tt = ttLib.TTFont("afont.ttf") # Load an existing font file
>> tt['maxp'].numGlyphs
>> tt['OS/2'].achVendID
>> tt['head'].unitsPerEm
For details of the objects returned when accessing each table, see :ref:`tables`.
To add a table to the font, use the :py:func:`newTable` function::
>> os2 = newTable("OS/2")
>> os2.version = 4
>> # set other attributes
>> font["OS/2"] = os2
TrueType fonts can also be serialized to and from XML format (see also the
:ref:`ttx` binary)::
>> tt.saveXML("afont.ttx")
Dumping 'LTSH' table...
Dumping 'OS/2' table...
>> tt2 = ttLib.TTFont() # Create a new font object
>> tt2.importXML("afont.ttx")
>> tt2['maxp'].numGlyphs
The TTFont object may be used as a context manager; this will cause the file
reader to be closed after the context ``with`` block is exited::
with TTFont(filename) as f:
# Do stuff
file: When reading a font from disk, either a pathname pointing to a file,
or a readable file object.
res_name_or_index: If running on a Macintosh, either a sfnt resource name or
an sfnt resource index number. If the index number is zero, TTLib will
autodetect whether the file is a flat file or a suitcase. (If it is a suitcase,
only the first 'sfnt' resource will be read.)
sfntVersion (str): When constructing a font object from scratch, sets the four-byte
sfnt magic number to be used. Defaults to ``\0\1\0\0`` (TrueType). To create
an OpenType file, use ``OTTO``.
flavor (str): Set this to ``woff`` when creating a WOFF file or ``woff2`` for a WOFF2
checkChecksums (int): How checksum data should be treated. Default is 0
(no checking). Set to 1 to check and warn on wrong checksums; set to 2 to
raise an exception if any wrong checksums are found.
recalcBBoxes (bool): If true (the default), recalculates ``glyf``, ``CFF ``,
``head`` bounding box values and ``hhea``/``vhea`` min/max values on save.
Also compiles the glyphs on importing, which saves memory consumption and
ignoreDecompileErrors (bool): If true, exceptions raised during table decompilation
will be ignored, and the binary data will be returned for those tables instead.
recalcTimestamp (bool): If true (the default), sets the ``modified`` timestamp in
the ``head`` table on save.
fontNumber (int): The index of the font in a TrueType Collection file.
lazy (bool): If lazy is set to True, many data structures are loaded lazily, upon
access only. If it is set to False, many data structures are loaded immediately.
The default is ``lazy=None`` which is somewhere in between.
def __init__(self, file=None, res_name_or_index=None,
sfntVersion="\000\001\000\000", flavor=None, checkChecksums=0,
verbose=None, recalcBBoxes=True, allowVID=NotImplemented, ignoreDecompileErrors=False,
recalcTimestamp=True, fontNumber=-1, lazy=None, quiet=None,
for name in ("verbose", "quiet"):
val = locals().get(name)
if val is not None:
deprecateArgument(name, "configure logging instead")
setattr(self, name, val)
self.lazy = lazy
self.recalcBBoxes = recalcBBoxes
self.recalcTimestamp = recalcTimestamp
self.tables = {}
self.reader = None
self.ignoreDecompileErrors = ignoreDecompileErrors
if not file:
self.sfntVersion = sfntVersion
self.flavor = flavor
self.flavorData = None
if not hasattr(file, "read"):
closeStream = True
# assume file is a string
if res_name_or_index is not None:
# see if it contains 'sfnt' resources in the resource or data fork
from . import macUtils
if res_name_or_index == 0:
if macUtils.getSFNTResIndices(file):
# get the first available sfnt font.
file = macUtils.SFNTResourceReader(file, 1)
file = open(file, "rb")
file = macUtils.SFNTResourceReader(file, res_name_or_index)
file = open(file, "rb")
# assume "file" is a readable file object
closeStream = False
if not self.lazy:
# read input file in memory and wrap a stream around it to allow overwriting
tmp = BytesIO(
if hasattr(file, 'name'):
# save reference to input file name =
if closeStream:
file = tmp
self._tableCache = _tableCache
self.reader = SFNTReader(file, checkChecksums, fontNumber=fontNumber)
self.sfntVersion = self.reader.sfntVersion
self.flavor = self.reader.flavor
self.flavorData = self.reader.flavorData
def __enter__(self):
return self
def __exit__(self, type, value, traceback):
def close(self):
"""If we still have a reader object, close it."""
if self.reader is not None:
def save(self, file, reorderTables=True):
"""Save the font to disk.
file: Similarly to the constructor, can be either a pathname or a writable
file object.
reorderTables (Option[bool]): If true (the default), reorder the tables,
sorting them by tag (recommended by the OpenType specification). If
false, retain the original font order. If None, reorder by table
dependency (fastest).
if not hasattr(file, "write"):
if self.lazy and == file:
raise TTLibError(
"Can't overwrite TTFont when 'lazy' attribute is True")
createStream = True
# assume "file" is a writable file object
createStream = False
tmp = BytesIO()
writer_reordersTables = self._save(tmp)
if not (reorderTables is None or writer_reordersTables or
(reorderTables is False and self.reader is None)):
if reorderTables is False:
# sort tables using the original font's order
tableOrder = list(self.reader.keys())
# use the recommended order from the OpenType specification
tableOrder = None
tmp2 = BytesIO()
reorderFontTables(tmp, tmp2, tableOrder)
tmp = tmp2
if createStream:
# "file" is a path
with open(file, "wb") as file:
def _save(self, file, tableCache=None):
"""Internal function, to be shared by save() and"""
if self.recalcTimestamp and 'head' in self:
self['head'] # make sure 'head' is loaded so the recalculation is actually done
tags = list(self.keys())
if "GlyphOrder" in tags:
numTables = len(tags)
# write to a temporary stream to allow saving to unseekable streams
writer = SFNTWriter(file, numTables, self.sfntVersion, self.flavor, self.flavorData)
done = []
for tag in tags:
self._writeTable(tag, writer, done, tableCache)
return writer.reordersTables()
def saveXML(self, fileOrPath, newlinestr="\n", **kwargs):
"""Export the font as TTX (an XML-based text file), or as a series of text
files when splitTables is true. In the latter case, the 'fileOrPath'
argument should be a path to a directory.
The 'tables' argument must either be false (dump all tables) or a
list of tables to dump. The 'skipTables' argument may be a list of tables
to skip, but only when the 'tables' argument is false.
writer = xmlWriter.XMLWriter(fileOrPath, newlinestr=newlinestr)
self._saveXML(writer, **kwargs)
def _saveXML(self, writer,
quiet=None, tables=None, skipTables=None, splitTables=False,
splitGlyphs=False, disassembleInstructions=True,
if quiet is not None:
deprecateArgument("quiet", "configure logging instead")
self.disassembleInstructions = disassembleInstructions
self.bitmapGlyphDataFormat = bitmapGlyphDataFormat
if not tables:
tables = list(self.keys())
if "GlyphOrder" not in tables:
tables = ["GlyphOrder"] + tables
if skipTables:
for tag in skipTables:
if tag in tables:
numTables = len(tables)
if writeVersion:
from fontTools import version
version = ".".join(version.split('.')[:2])
writer.begintag("ttFont", sfntVersion=repr(tostr(self.sfntVersion))[1:-1],
writer.begintag("ttFont", sfntVersion=repr(tostr(self.sfntVersion))[1:-1])
# always splitTables if splitGlyphs is enabled
splitTables = splitTables or splitGlyphs
if not splitTables:
path, ext = os.path.splitext(writer.filename)
fileNameTemplate = path + ".%s" + ext
for i in range(numTables):
tag = tables[i]
if splitTables:
tablePath = fileNameTemplate % tagToIdentifier(tag)
tableWriter = xmlWriter.XMLWriter(tablePath,
tableWriter.begintag("ttFont", ttLibVersion=version)
writer.simpletag(tagToXML(tag), src=os.path.basename(tablePath))
tableWriter = writer
self._tableToXML(tableWriter, tag, splitGlyphs=splitGlyphs)
if splitTables:
def _tableToXML(self, writer, tag, quiet=None, splitGlyphs=False):
if quiet is not None:
deprecateArgument("quiet", "configure logging instead")
if tag in self:
table = self[tag]
report = "Dumping '%s' table..." % tag
report = "No '%s' table found." % tag
if tag not in self:
xmlTag = tagToXML(tag)
attrs = dict()
if hasattr(table, "ERROR"):
attrs['ERROR'] = "decompilation error"
from .tables.DefaultTable import DefaultTable
if table.__class__ == DefaultTable:
attrs['raw'] = True
writer.begintag(xmlTag, **attrs)
if tag == "glyf":
table.toXML(writer, self, splitGlyphs=splitGlyphs)
table.toXML(writer, self)
def importXML(self, fileOrPath, quiet=None):
"""Import a TTX file (an XML-based text format), so as to recreate
a font object.
if quiet is not None:
deprecateArgument("quiet", "configure logging instead")
if "maxp" in self and "post" in self:
# Make sure the glyph order is loaded, as it otherwise gets
# lost if the XML doesn't contain the glyph order, yet does
# contain the table which was originally used to extract the
# glyph names from (ie. 'post', 'cmap' or 'CFF ').
from fontTools.misc import xmlReader
reader = xmlReader.XMLReader(fileOrPath, self)
def isLoaded(self, tag):
"""Return true if the table identified by ``tag`` has been
decompiled and loaded into memory."""
return tag in self.tables
def has_key(self, tag):
"""Test if the table identified by ``tag`` is present in the font.
As well as this method, ``tag in font`` can also be used to determine the
presence of the table."""
if self.isLoaded(tag):
return True
elif self.reader and tag in self.reader:
return True
elif tag == "GlyphOrder":
return True
return False
__contains__ = has_key
def keys(self):
"""Returns the list of tables in the font, along with the ``GlyphOrder`` pseudo-table."""
keys = list(self.tables.keys())
if self.reader:
for key in list(self.reader.keys()):
if key not in keys:
if "GlyphOrder" in keys:
keys = sortedTagList(keys)
return ["GlyphOrder"] + keys
def __len__(self):
return len(list(self.keys()))
def __getitem__(self, tag):
tag = Tag(tag)
table = self.tables.get(tag)
if table is None:
if tag == "GlyphOrder":
table = GlyphOrder(tag)
self.tables[tag] = table
elif self.reader is not None:
table = self._readTable(tag)
raise KeyError("'%s' table not found" % tag)
return table
def _readTable(self, tag):
log.debug("Reading '%s' table from disk", tag)
data = self.reader[tag]
if self._tableCache is not None:
table = self._tableCache.get((tag, data))
if table is not None:
return table
tableClass = getTableClass(tag)
table = tableClass(tag)
self.tables[tag] = table
log.debug("Decompiling '%s' table", tag)
table.decompile(data, self)
except Exception:
if not self.ignoreDecompileErrors:
# fall back to DefaultTable, retaining the binary table data
"An exception occurred during the decompilation of the '%s' table", tag)
from .tables.DefaultTable import DefaultTable
file = StringIO()
table = DefaultTable(tag)
table.ERROR = file.getvalue()
self.tables[tag] = table
table.decompile(data, self)
if self._tableCache is not None:
self._tableCache[(tag, data)] = table
return table
def __setitem__(self, tag, table):
self.tables[Tag(tag)] = table
def __delitem__(self, tag):
if tag not in self:
raise KeyError("'%s' table not found" % tag)
if tag in self.tables:
del self.tables[tag]
if self.reader and tag in self.reader:
del self.reader[tag]
def get(self, tag, default=None):
"""Returns the table if it exists or (optionally) a default if it doesn't."""
return self[tag]
except KeyError:
return default
def setGlyphOrder(self, glyphOrder):
"""Set the glyph order
glyphOrder ([str]): List of glyph names in order.
self.glyphOrder = glyphOrder
if hasattr(self, '_reverseGlyphOrderDict'):
del self._reverseGlyphOrderDict
def getGlyphOrder(self):
"""Returns a list of glyph names ordered by their position in the font."""
return self.glyphOrder
except AttributeError:
if 'CFF ' in self:
cff = self['CFF ']
self.glyphOrder = cff.getGlyphOrder()
elif 'post' in self:
# TrueType font
glyphOrder = self['post'].getGlyphOrder()
if glyphOrder is None:
# No names found in the 'post' table.
# Try to create glyph names from the unicode cmap (if available)
# in combination with the Adobe Glyph List (AGL).
self.glyphOrder = glyphOrder
return self.glyphOrder
def _getGlyphNamesFromCmap(self):
# This is rather convoluted, but then again, it's an interesting problem:
# - we need to use the unicode values found in the cmap table to
# build glyph names (eg. because there is only a minimal post table,
# or none at all).
# - but the cmap parser also needs glyph names to work with...
# So here's what we do:
# - make up glyph names based on glyphID
# - load a temporary cmap table based on those names
# - extract the unicode values, build the "real" glyph names
# - unload the temporary cmap table
if self.isLoaded("cmap"):
# Bootstrapping: we're getting called by the cmap parser
# itself. This means self.tables['cmap'] contains a partially
# loaded cmap, making it impossible to get at a unicode
# subtable here. We remove the partially loaded cmap and
# restore it later.
# This only happens if the cmap table is loaded before any
# other table that does f.getGlyphOrder() or f.getGlyphName().
cmapLoading = self.tables['cmap']
del self.tables['cmap']
cmapLoading = None
# Make up glyph names based on glyphID, which will be used by the
# temporary cmap and by the real cmap in case we don't find a unicode
# cmap.
numGlyphs = int(self['maxp'].numGlyphs)
glyphOrder = [None] * numGlyphs
glyphOrder[0] = ".notdef"
for i in range(1, numGlyphs):
glyphOrder[i] = "glyph%.5d" % i
# Set the glyph order, so the cmap parser has something
# to work with (so we don't get called recursively).
self.glyphOrder = glyphOrder
# Make up glyph names based on the reversed cmap table. Because some
# glyphs (eg. ligatures or alternates) may not be reachable via cmap,
# this naming table will usually not cover all glyphs in the font.
# If the font has no Unicode cmap table, reversecmap will be empty.
if 'cmap' in self:
reversecmap = self['cmap'].buildReversed()
reversecmap = {}
useCount = {}
for i in range(numGlyphs):
tempName = glyphOrder[i]
if tempName in reversecmap:
# If a font maps both U+0041 LATIN CAPITAL LETTER A and
# U+0391 GREEK CAPITAL LETTER ALPHA to the same glyph,
# we prefer naming the glyph as "A".
glyphName = self._makeGlyphName(min(reversecmap[tempName]))
numUses = useCount[glyphName] = useCount.get(glyphName, 0) + 1
if numUses > 1:
glyphName = "%s.alt%d" % (glyphName, numUses - 1)
glyphOrder[i] = glyphName
if 'cmap' in self:
# Delete the temporary cmap table from the cache, so it can
# be parsed again with the right names.
del self.tables['cmap']
self.glyphOrder = glyphOrder
if cmapLoading:
# restore partially loaded cmap, so it can continue loading
# using the proper names.
self.tables['cmap'] = cmapLoading
def _makeGlyphName(codepoint):
from fontTools import agl # Adobe Glyph List
if codepoint in agl.UV2AGL:
return agl.UV2AGL[codepoint]
elif codepoint <= 0xFFFF:
return "uni%04X" % codepoint
return "u%X" % codepoint
def getGlyphNames(self):
"""Get a list of glyph names, sorted alphabetically."""
glyphNames = sorted(self.getGlyphOrder())
return glyphNames
def getGlyphNames2(self):
"""Get a list of glyph names, sorted alphabetically,
but not case sensitive.
from fontTools.misc import textTools
return textTools.caselessSort(self.getGlyphOrder())
def getGlyphName(self, glyphID):
"""Returns the name for the glyph with the given ID.
If no name is available, synthesises one with the form ``glyphXXXXX``` where
```XXXXX`` is the zero-padded glyph ID.
return self.getGlyphOrder()[glyphID]
except IndexError:
return "glyph%.5d" % glyphID
def getGlyphNameMany(self, lst):
"""Converts a list of glyph IDs into a list of glyph names."""
glyphOrder = self.getGlyphOrder();
cnt = len(glyphOrder)
return [glyphOrder[gid] if gid < cnt else "glyph%.5d" % gid
for gid in lst]
def getGlyphID(self, glyphName):
"""Returns the ID of the glyph with the given name."""
return self.getReverseGlyphMap()[glyphName]
except KeyError:
if glyphName[:5] == "glyph":
return int(glyphName[5:])
except (NameError, ValueError):
raise KeyError(glyphName)
def getGlyphIDMany(self, lst):
"""Converts a list of glyph names into a list of glyph IDs."""
d = self.getReverseGlyphMap()
return [d[glyphName] for glyphName in lst]
except KeyError:
getGlyphID = self.getGlyphID
return [getGlyphID(glyphName) for glyphName in lst]
def getReverseGlyphMap(self, rebuild=False):
"""Returns a mapping of glyph names to glyph IDs."""
if rebuild or not hasattr(self, "_reverseGlyphOrderDict"):
return self._reverseGlyphOrderDict
def _buildReverseGlyphOrderDict(self):
self._reverseGlyphOrderDict = d = {}
for glyphID,glyphName in enumerate(self.getGlyphOrder()):
d[glyphName] = glyphID
return d
def _writeTable(self, tag, writer, done, tableCache=None):
"""Internal helper function for Keeps track of
inter-table dependencies.
if tag in done:
tableClass = getTableClass(tag)
for masterTable in tableClass.dependencies:
if masterTable not in done:
if masterTable in self:
self._writeTable(masterTable, writer, done, tableCache)
tabledata = self.getTableData(tag)
if tableCache is not None:
entry = tableCache.get((Tag(tag), tabledata))
if entry is not None:
log.debug("reusing '%s' table", tag)
writer.setEntry(tag, entry)
log.debug("Writing '%s' table to disk", tag)
writer[tag] = tabledata
if tableCache is not None:
tableCache[(Tag(tag), tabledata)] = writer[tag]
def getTableData(self, tag):
"""Returns the binary representation of a table.
If the table is currently loaded and in memory, the data is compiled to
binary and returned; if it is not currently loaded, the binary data is
read from the font file and returned.
tag = Tag(tag)
if self.isLoaded(tag):
log.debug("Compiling '%s' table", tag)
return self.tables[tag].compile(self)
elif self.reader and tag in self.reader:
log.debug("Reading '%s' table from disk", tag)
return self.reader[tag]
raise KeyError(tag)
def getGlyphSet(self, preferCFF=True):
"""Return a generic GlyphSet, which is a dict-like object
mapping glyph names to glyph objects. The returned glyph objects
have a .draw() method that supports the Pen protocol, and will
have an attribute named 'width'.
If the font is CFF-based, the outlines will be taken from the 'CFF ' or
'CFF2' tables. Otherwise the outlines will be taken from the 'glyf' table.
If the font contains both a 'CFF '/'CFF2' and a 'glyf' table, you can use
the 'preferCFF' argument to specify which one should be taken. If the
font contains both a 'CFF ' and a 'CFF2' table, the latter is taken.
glyphs = None
if (preferCFF and any(tb in self for tb in ["CFF ", "CFF2"]) or
("glyf" not in self and any(tb in self for tb in ["CFF ", "CFF2"]))):
table_tag = "CFF2" if "CFF2" in self else "CFF "
glyphs = _TTGlyphSet(self,
list(self[table_tag].cff.values())[0].CharStrings, _TTGlyphCFF)
if glyphs is None and "glyf" in self:
glyphs = _TTGlyphSet(self, self["glyf"], _TTGlyphGlyf)
if glyphs is None:
raise TTLibError("Font contains no outlines")
return glyphs
def getBestCmap(self, cmapPreferences=((3, 10), (0, 6), (0, 4), (3, 1), (0, 3), (0, 2), (0, 1), (0, 0))):
"""Return the 'best' unicode cmap dictionary available in the font,
or None, if no unicode cmap subtable is available.
By default it will search for the following (platformID, platEncID)
(3, 10),
(0, 6),
(0, 4),
(3, 1),
(0, 3),
(0, 2),
(0, 1),
(0, 0)
This can be customized via the ``cmapPreferences`` argument.
return self["cmap"].getBestCmap(cmapPreferences=cmapPreferences)
class _TTGlyphSet(object):
"""Generic dict-like GlyphSet class that pulls metrics from hmtx and
glyph shape from TrueType or CFF.
def __init__(self, ttFont, glyphs, glyphType):
"""Construct a new glyphset.
font (TTFont): The font object (used to get metrics).
glyphs (dict): A dictionary mapping glyph names to ``_TTGlyph`` objects.
glyphType (class): Either ``_TTGlyphCFF`` or ``_TTGlyphGlyf``.
self._glyphs = glyphs
self._hmtx = ttFont['hmtx']
self._vmtx = ttFont['vmtx'] if 'vmtx' in ttFont else None
self._glyphType = glyphType
def keys(self):
return list(self._glyphs.keys())
def has_key(self, glyphName):
return glyphName in self._glyphs
__contains__ = has_key
def __getitem__(self, glyphName):
horizontalMetrics = self._hmtx[glyphName]
verticalMetrics = self._vmtx[glyphName] if self._vmtx else None
return self._glyphType(
self, self._glyphs[glyphName], horizontalMetrics, verticalMetrics)
def __len__(self):
return len(self._glyphs)
def get(self, glyphName, default=None):
return self[glyphName]
except KeyError:
return default
class _TTGlyph(object):
"""Wrapper for a TrueType glyph that supports the Pen protocol, meaning
that it has .draw() and .drawPoints() methods that take a pen object as
their only argument. Additionally there are 'width' and 'lsb' attributes,
read from the 'hmtx' table.
If the font contains a 'vmtx' table, there will also be 'height' and 'tsb'
def __init__(self, glyphset, glyph, horizontalMetrics, verticalMetrics=None):
"""Construct a new _TTGlyph.
glyphset (_TTGlyphSet): A glyphset object used to resolve components.
glyph (ttLib.tables._g_l_y_f.Glyph): The glyph object.
horizontalMetrics (int, int): The glyph's width and left sidebearing.
self._glyphset = glyphset
self._glyph = glyph
self.width, self.lsb = horizontalMetrics
if verticalMetrics:
self.height, self.tsb = verticalMetrics
self.height, self.tsb = None, None
def draw(self, pen):
"""Draw the glyph onto ``pen``. See fontTools.pens.basePen for details
how that works.
def drawPoints(self, pen):
# drawPoints is only implemented for _TTGlyphGlyf at this time.
raise NotImplementedError()
class _TTGlyphCFF(_TTGlyph):
class _TTGlyphGlyf(_TTGlyph):
def draw(self, pen):
"""Draw the glyph onto Pen. See fontTools.pens.basePen for details
how that works.
glyfTable = self._glyphset._glyphs
glyph = self._glyph
offset = self.lsb - glyph.xMin if hasattr(glyph, "xMin") else 0
glyph.draw(pen, glyfTable, offset)
def drawPoints(self, pen):
"""Draw the glyph onto PointPen. See fontTools.pens.pointPen
for details how that works.
glyfTable = self._glyphset._glyphs
glyph = self._glyph
offset = self.lsb - glyph.xMin if hasattr(glyph, "xMin") else 0
glyph.drawPoints(pen, glyfTable, offset)
class GlyphOrder(object):
"""A pseudo table. The glyph order isn't in the font as a separate
table, but it's nice to present it as such in the TTX format.
def __init__(self, tag=None):
def toXML(self, writer, ttFont):
glyphOrder = ttFont.getGlyphOrder()
writer.comment("The 'id' attribute is only for humans; "
"it is ignored when parsed.")
for i in range(len(glyphOrder)):
glyphName = glyphOrder[i]
writer.simpletag("GlyphID", id=i, name=glyphName)
def fromXML(self, name, attrs, content, ttFont):
if not hasattr(self, "glyphOrder"):
self.glyphOrder = []
if name == "GlyphID":
def getTableModule(tag):
"""Fetch the packer/unpacker module for a table.
Return None when no module is found.
from . import tables
pyTag = tagToIdentifier(tag)
__import__("fontTools.ttLib.tables." + pyTag)
except ImportError as err:
# If pyTag is found in the ImportError message,
# means table is not implemented. If it's not
# there, then some other module is missing, don't
# suppress the error.
if str(err).find(pyTag) >= 0:
return None
raise err
return getattr(tables, pyTag)
# Registry for custom table packer/unpacker classes. Keys are table
# tags, values are (moduleName, className) tuples.
# See registerCustomTableClass() and getCustomTableClass()
_customTableRegistry = {}
def registerCustomTableClass(tag, moduleName, className=None):
"""Register a custom packer/unpacker class for a table.
The 'moduleName' must be an importable module. If no 'className'
is given, it is derived from the tag, for example it will be
``table_C_U_S_T_`` for a 'CUST' tag.
The registered table class should be a subclass of
if className is None:
className = "table_" + tagToIdentifier(tag)
_customTableRegistry[tag] = (moduleName, className)
def unregisterCustomTableClass(tag):
"""Unregister the custom packer/unpacker class for a table."""
del _customTableRegistry[tag]
def getCustomTableClass(tag):
"""Return the custom table class for tag, if one has been registered
with 'registerCustomTableClass()'. Else return None.
if tag not in _customTableRegistry:
return None
import importlib
moduleName, className = _customTableRegistry[tag]
module = importlib.import_module(moduleName)
return getattr(module, className)
def getTableClass(tag):
"""Fetch the packer/unpacker class for a table."""
tableClass = getCustomTableClass(tag)
if tableClass is not None:
return tableClass
module = getTableModule(tag)
if module is None:
from .tables.DefaultTable import DefaultTable
return DefaultTable
pyTag = tagToIdentifier(tag)
tableClass = getattr(module, "table_" + pyTag)
return tableClass
def getClassTag(klass):
"""Fetch the table tag for a class object."""
name = klass.__name__
assert name[:6] == 'table_'
name = name[6:] # Chop 'table_'
return identifierToTag(name)
def newTable(tag):
"""Return a new instance of a table."""
tableClass = getTableClass(tag)
return tableClass(tag)
def _escapechar(c):
"""Helper function for tagToIdentifier()"""
import re
if re.match("[a-z0-9]", c):
return "_" + c
elif re.match("[A-Z]", c):
return c + "_"
return hex(byteord(c))[2:]
def tagToIdentifier(tag):
"""Convert a table tag to a valid (but UGLY) python identifier,
as well as a filename that's guaranteed to be unique even on a
caseless file system. Each character is mapped to two characters.
Lowercase letters get an underscore before the letter, uppercase
letters get an underscore after the letter. Trailing spaces are
trimmed. Illegal characters are escaped as two hex bytes. If the
result starts with a number (as the result of a hex escape), an
extra underscore is prepended. Examples::
>>> tagToIdentifier('glyf')
>>> tagToIdentifier('cvt ')
>>> tagToIdentifier('OS/2')
import re
tag = Tag(tag)
if tag == "GlyphOrder":
return tag
assert len(tag) == 4, "tag should be 4 characters long"
while len(tag) > 1 and tag[-1] == ' ':
tag = tag[:-1]
ident = ""
for c in tag:
ident = ident + _escapechar(c)
if re.match("[0-9]", ident):
ident = "_" + ident
return ident
def identifierToTag(ident):
"""the opposite of tagToIdentifier()"""
if ident == "GlyphOrder":
return ident
if len(ident) % 2 and ident[0] == "_":
ident = ident[1:]
assert not (len(ident) % 2)
tag = ""
for i in range(0, len(ident), 2):
if ident[i] == "_":
tag = tag + ident[i+1]
elif ident[i+1] == "_":
tag = tag + ident[i]
# assume hex
tag = tag + chr(int(ident[i:i+2], 16))
# append trailing spaces
tag = tag + (4 - len(tag)) * ' '
return Tag(tag)
def tagToXML(tag):
"""Similarly to tagToIdentifier(), this converts a TT tag
to a valid XML element name. Since XML element names are
case sensitive, this is a fairly simple/readable translation.
import re
tag = Tag(tag)
if tag == "OS/2":
return "OS_2"
elif tag == "GlyphOrder":
return tag
if re.match("[A-Za-z_][A-Za-z_0-9]* *$", tag):
return tag.strip()
return tagToIdentifier(tag)
def xmlToTag(tag):
"""The opposite of tagToXML()"""
if tag == "OS_2":
return Tag("OS/2")
if len(tag) == 8:
return identifierToTag(tag)
return Tag(tag + " " * (4 - len(tag)))
# Table order as recommended in the OpenType specification 1.4
TTFTableOrder = ["head", "hhea", "maxp", "OS/2", "hmtx", "LTSH", "VDMX",
"hdmx", "cmap", "fpgm", "prep", "cvt ", "loca", "glyf",
"kern", "name", "post", "gasp", "PCLT"]
OTFTableOrder = ["head", "hhea", "maxp", "OS/2", "name", "cmap", "post",
"CFF "]
def sortedTagList(tagList, tableOrder=None):
"""Return a sorted copy of tagList, sorted according to the OpenType
specification, or according to a custom tableOrder. If given and not
None, tableOrder needs to be a list of tag names.
tagList = sorted(tagList)
if tableOrder is None:
if "DSIG" in tagList:
# DSIG should be last (XXX spec reference?)
if "CFF " in tagList:
tableOrder = OTFTableOrder
tableOrder = TTFTableOrder
orderedTables = []
for tag in tableOrder:
if tag in tagList:
return orderedTables
def reorderFontTables(inFile, outFile, tableOrder=None, checkChecksums=False):
"""Rewrite a font file, ordering the tables as recommended by the
OpenType specification 1.4.
reader = SFNTReader(inFile, checkChecksums=checkChecksums)
writer = SFNTWriter(outFile, len(reader.tables), reader.sfntVersion, reader.flavor, reader.flavorData)
tables = list(reader.keys())
for tag in sortedTagList(tables, tableOrder):
writer[tag] = reader[tag]
def maxPowerOfTwo(x):
"""Return the highest exponent of two, so that
(2 ** exponent) <= x. Return 0 if x is 0.
exponent = 0
while x:
x = x >> 1
exponent = exponent + 1
return max(exponent - 1, 0)
def getSearchRange(n, itemSize=16):
"""Calculate searchRange, entrySelector, rangeShift.
# itemSize defaults to 16, for backward compatibility
# with upstream fonttools.
exponent = maxPowerOfTwo(n)
searchRange = (2 ** exponent) * itemSize
entrySelector = exponent
rangeShift = max(0, n * itemSize - searchRange)
return searchRange, entrySelector, rangeShift