Source code for fontTools.ttLib.tables._h_e_a_d

from fontTools.misc import sstruct
from fontTools.misc.fixedTools import floatToFixedToStr, strToFixedToFloat
from fontTools.misc.textTools import safeEval, num2binary, binary2num
from fontTools.misc.timeTools import (
    timestampFromString,
    timestampToString,
    timestampNow,
)
from fontTools.misc.timeTools import epoch_diff as mac_epoch_diff  # For backward compat
from fontTools.misc.arrayTools import intRect, unionRect
from . import DefaultTable
import logging


log = logging.getLogger(__name__)

headFormat = """
		>	# big endian
		tableVersion:       16.16F
		fontRevision:       16.16F
		checkSumAdjustment: I
		magicNumber:        I
		flags:              H
		unitsPerEm:         H
		created:            Q
		modified:           Q
		xMin:               h
		yMin:               h
		xMax:               h
		yMax:               h
		macStyle:           H
		lowestRecPPEM:      H
		fontDirectionHint:  h
		indexToLocFormat:   h
		glyphDataFormat:    h
"""


[docs] class table__h_e_a_d(DefaultTable.DefaultTable): dependencies = ["maxp", "loca", "CFF ", "CFF2"]
[docs] def decompile(self, data, ttFont): dummy, rest = sstruct.unpack2(headFormat, data, self) if rest: # this is quite illegal, but there seem to be fonts out there that do this log.warning("extra bytes at the end of 'head' table") assert rest == b"\0\0" # For timestamp fields, ignore the top four bytes. Some fonts have # bogus values there. Since till 2038 those bytes only can be zero, # ignore them. # # https://github.com/fonttools/fonttools/issues/99#issuecomment-66776810 for stamp in "created", "modified": value = getattr(self, stamp) if value > 0xFFFFFFFF: log.warning("'%s' timestamp out of range; ignoring top bytes", stamp) value &= 0xFFFFFFFF setattr(self, stamp, value) if value < 0x7C259DC0: # January 1, 1970 00:00:00 log.warning( "'%s' timestamp seems very low; regarding as unix timestamp", stamp ) value += 0x7C259DC0 setattr(self, stamp, value)
[docs] def compile(self, ttFont): if ttFont.recalcBBoxes: # For TT-flavored fonts, xMin, yMin, xMax and yMax are set in table__m_a_x_p.recalc(). if "CFF " in ttFont: topDict = ttFont["CFF "].cff.topDictIndex[0] self.xMin, self.yMin, self.xMax, self.yMax = intRect(topDict.FontBBox) elif "CFF2" in ttFont: topDict = ttFont["CFF2"].cff.topDictIndex[0] charStrings = topDict.CharStrings fontBBox = None for charString in charStrings.values(): bounds = charString.calcBounds(charStrings) if bounds is not None: if fontBBox is not None: fontBBox = unionRect(fontBBox, bounds) else: fontBBox = bounds if fontBBox is not None: self.xMin, self.yMin, self.xMax, self.yMax = intRect(fontBBox) if ttFont.recalcTimestamp: self.modified = timestampNow() data = sstruct.pack(headFormat, self) return data
[docs] def toXML(self, writer, ttFont): writer.comment("Most of this table will be recalculated by the compiler") writer.newline() _, names, fixes = sstruct.getformat(headFormat) for name in names: value = getattr(self, name) if name in fixes: value = floatToFixedToStr(value, precisionBits=fixes[name]) elif name in ("created", "modified"): value = timestampToString(value) elif name in ("magicNumber", "checkSumAdjustment"): if value < 0: value = value + 0x100000000 value = hex(value) if value[-1:] == "L": value = value[:-1] elif name in ("macStyle", "flags"): value = num2binary(value, 16) writer.simpletag(name, value=value) writer.newline()
[docs] def fromXML(self, name, attrs, content, ttFont): value = attrs["value"] fixes = sstruct.getformat(headFormat)[2] if name in fixes: value = strToFixedToFloat(value, precisionBits=fixes[name]) elif name in ("created", "modified"): value = timestampFromString(value) elif name in ("macStyle", "flags"): value = binary2num(value) else: value = safeEval(value) setattr(self, name, value)