Traktor/myenv/Lib/site-packages/fontTools/varLib/builder.py
2024-05-23 01:57:24 +02:00

158 lines
4.7 KiB
Python

from fontTools import ttLib
from fontTools.ttLib.tables import otTables as ot
# VariationStore
def buildVarRegionAxis(axisSupport):
self = ot.VarRegionAxis()
self.StartCoord, self.PeakCoord, self.EndCoord = [float(v) for v in axisSupport]
return self
def buildVarRegion(support, axisTags):
assert all(tag in axisTags for tag in support.keys()), (
"Unknown axis tag found.",
support,
axisTags,
)
self = ot.VarRegion()
self.VarRegionAxis = []
for tag in axisTags:
self.VarRegionAxis.append(buildVarRegionAxis(support.get(tag, (0, 0, 0))))
return self
def buildVarRegionList(supports, axisTags):
self = ot.VarRegionList()
self.RegionAxisCount = len(axisTags)
self.Region = []
for support in supports:
self.Region.append(buildVarRegion(support, axisTags))
self.RegionCount = len(self.Region)
return self
def _reorderItem(lst, mapping):
return [lst[i] for i in mapping]
def VarData_calculateNumShorts(self, optimize=False):
count = self.VarRegionCount
items = self.Item
bit_lengths = [0] * count
for item in items:
# The "+ (i < -1)" magic is to handle two's-compliment.
# That is, we want to get back 7 for -128, whereas
# bit_length() returns 8. Similarly for -65536.
# The reason "i < -1" is used instead of "i < 0" is that
# the latter would make it return 0 for "-1" instead of 1.
bl = [(i + (i < -1)).bit_length() for i in item]
bit_lengths = [max(*pair) for pair in zip(bl, bit_lengths)]
# The addition of 8, instead of seven, is to account for the sign bit.
# This "((b + 8) >> 3) if b else 0" when combined with the above
# "(i + (i < -1)).bit_length()" is a faster way to compute byte-lengths
# conforming to:
#
# byte_length = (0 if i == 0 else
# 1 if -128 <= i < 128 else
# 2 if -65536 <= i < 65536 else
# ...)
byte_lengths = [((b + 8) >> 3) if b else 0 for b in bit_lengths]
# https://github.com/fonttools/fonttools/issues/2279
longWords = any(b > 2 for b in byte_lengths)
if optimize:
# Reorder columns such that wider columns come before narrower columns
mapping = []
mapping.extend(i for i, b in enumerate(byte_lengths) if b > 2)
mapping.extend(i for i, b in enumerate(byte_lengths) if b == 2)
mapping.extend(i for i, b in enumerate(byte_lengths) if b == 1)
byte_lengths = _reorderItem(byte_lengths, mapping)
self.VarRegionIndex = _reorderItem(self.VarRegionIndex, mapping)
self.VarRegionCount = len(self.VarRegionIndex)
for i in range(len(items)):
items[i] = _reorderItem(items[i], mapping)
if longWords:
self.NumShorts = (
max((i for i, b in enumerate(byte_lengths) if b > 2), default=-1) + 1
)
self.NumShorts |= 0x8000
else:
self.NumShorts = (
max((i for i, b in enumerate(byte_lengths) if b > 1), default=-1) + 1
)
self.VarRegionCount = len(self.VarRegionIndex)
return self
ot.VarData.calculateNumShorts = VarData_calculateNumShorts
def VarData_CalculateNumShorts(self, optimize=True):
"""Deprecated name for VarData_calculateNumShorts() which
defaults to optimize=True. Use varData.calculateNumShorts()
or varData.optimize()."""
return VarData_calculateNumShorts(self, optimize=optimize)
def VarData_optimize(self):
return VarData_calculateNumShorts(self, optimize=True)
ot.VarData.optimize = VarData_optimize
def buildVarData(varRegionIndices, items, optimize=True):
self = ot.VarData()
self.VarRegionIndex = list(varRegionIndices)
regionCount = self.VarRegionCount = len(self.VarRegionIndex)
records = self.Item = []
if items:
for item in items:
assert len(item) == regionCount
records.append(list(item))
self.ItemCount = len(self.Item)
self.calculateNumShorts(optimize=optimize)
return self
def buildVarStore(varRegionList, varDataList):
self = ot.VarStore()
self.Format = 1
self.VarRegionList = varRegionList
self.VarData = list(varDataList)
self.VarDataCount = len(self.VarData)
return self
# Variation helpers
def buildVarIdxMap(varIdxes, glyphOrder):
self = ot.VarIdxMap()
self.mapping = {g: v for g, v in zip(glyphOrder, varIdxes)}
return self
def buildDeltaSetIndexMap(varIdxes):
mapping = list(varIdxes)
if all(i == v for i, v in enumerate(mapping)):
return None
self = ot.DeltaSetIndexMap()
self.mapping = mapping
self.Format = 1 if len(mapping) > 0xFFFF else 0
return self
def buildVarDevTable(varIdx):
self = ot.Device()
self.DeltaFormat = 0x8000
self.StartSize = varIdx >> 16
self.EndSize = varIdx & 0xFFFF
return self