def _getIndicGlyphs(self):
cmap = self.makeUnicodeToGlyphNameMapping()
unicodeIsIndic = partial(unicodeInScripts, scripts=self.indicScripts)
if any(unicodeIsIndic for uv in cmap):
# If there are any characters from Indic scripts in the cmap, we
# compile a temporary GSUB table to resolve substitutions and get
# the set of all the "Indic" glyphs, including alternate glyphs.
gsub = self.compileGSUB()
glyphGroups = classifyGlyphs(unicodeIsIndic, cmap, gsub)
# the 'glyphGroups' dict is keyed by the return value of the
# classifying include, so here 'True' means all the Indic glyphs
return glyphGroups.get(True, set())
else:
return set()
def _makeKerningLookups(self):
cmap = self.makeUnicodeToGlyphNameMapping()
if any(unicodeScriptDirection(uv) == "RTL" for uv in cmap):
# If there are any characters from globally RTL scripts in the
# cmap, we compile a temporary GSUB table to resolve substitutions
# and group glyphs by script horizontal direction and bidirectional
# type. We then mark each kerning pair with these properties when
# any of the glyphs involved in a pair intersects these groups.
gsub = self.compileGSUB()
dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub)
directions = self._intersectPairs("directions", dirGlyphs)
shouldSplit = "RTL" in directions
if shouldSplit:
bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub)
self._intersectPairs("bidiTypes", bidiGlyphs)
else:
shouldSplit = False
marks = self.context.gdefClasses.mark
lookups = {}
if shouldSplit:
# make one DFLT lookup with script-agnostic characters, and two
# LTR/RTL lookups excluding pairs from the opposite group.
# We drop kerning pairs with ambiguous direction: i.e. those containing
# glyphs from scripts with different overall horizontal direction, or
# glyphs with incompatible bidirectional type (e.g. arabic letters vs
# arabic numerals).
pairs = []
for pair in self.context.kerning.pairs:
if ("RTL" in pair.directions and "LTR" in pair.directions) or (
"R" in pair.bidiTypes and "L" in pair.bidiTypes):
self.log.warning(
"skipped kern pair with ambiguous direction: %r", pair)
continue
pairs.append(pair)
if not pairs:
return lookups
if self.options.ignoreMarks:
# If there are pairs with a mix of mark/base then the IgnoreMarks
# flag is unnecessary and should not be set
basePairs, markPairs = self._splitBaseAndMarkPairs(
pairs, marks)
self._makeSplitDirectionKernLookups(lookups, basePairs)
if markPairs:
self._makeSplitDirectionKernLookups(lookups,
markPairs,
ignoreMarks=False,
suffix="_marks")
else:
self._makeSplitDirectionKernLookups(lookups, pairs)
else:
# only make a single (implicitly LTR) lookup including all base/base pairs
# and a single lookup including all base/mark pairs (if any)
pairs = self.context.kerning.pairs
if self.options.ignoreMarks:
basePairs, markPairs = self._splitBaseAndMarkPairs(
pairs, marks)
lookups["LTR"] = [
self._makeKerningLookup("kern_ltr", basePairs)
]
if markPairs:
lookups["LTR"].append(
self._makeKerningLookup("kern_ltr_marks",
markPairs,
ignoreMarks=False))
else:
lookups["LTR"] = [self._makeKerningLookup("kern_ltr", pairs)]
return lookups
def _makeKerningLookups(self):
cmap = self.makeUnicodeToGlyphNameMapping()
if any(unicodeScriptDirection(uv) == "RTL" for uv in cmap):
# If there are any characters from globally RTL scripts in the
# cmap, we compile a temporary GSUB table to resolve substitutions
# and group glyphs by script horizontal direction and bidirectional
# type. We then mark each kerning pair with these properties when
# any of the glyphs involved in a pair intersects these groups.
gsub = self.compileGSUB()
dirGlyphs = classifyGlyphs(unicodeScriptDirection, cmap, gsub)
directions = self._intersectPairs("directions", dirGlyphs)
shouldSplit = "RTL" in directions
if shouldSplit:
bidiGlyphs = classifyGlyphs(unicodeBidiType, cmap, gsub)
self._intersectPairs("bidiTypes", bidiGlyphs)
else:
shouldSplit = False
lookups = {}
if shouldSplit:
# make one DFLT lookup with script-agnostic characters, and two
# LTR/RTL lookups excluding pairs from the opposite group.
# We drop kerning pairs with ambiguous direction.
pairs = []
for pair in self.context.kerning.pairs:
if "RTL" in pair.directions and "LTR" in pair.directions:
self.log.warning(
"skipped kern pair with ambiguous direction: %r", pair)
continue
pairs.append(pair)
if not pairs:
return lookups
dfltKern = self._makeKerningLookup(
"kern_dflt",
pairs,
exclude=(
lambda pair: {"LTR", "RTL"}.intersection(pair.directions)),
rtl=False,
)
if dfltKern:
lookups["DFLT"] = dfltKern
ltrKern = self._makeKerningLookup(
"kern_ltr",
pairs,
exclude=(lambda pair: not pair.directions or "RTL" in pair.
directions),
rtl=False,
)
if ltrKern:
lookups["LTR"] = ltrKern
rtlKern = self._makeKerningLookup(
"kern_rtl",
pairs,
exclude=(lambda pair: not pair.directions or "LTR" in pair.
directions),
rtl=True,
)
if rtlKern:
lookups["RTL"] = rtlKern
else:
# only make a single (implicitly LTR) lookup including all pairs
lookups["LTR"] = self._makeKerningLookup(
"kern_ltr", self.context.kerning.pairs)
return lookups
