""" TSI{0,1,2,3,5} are private tables used by Microsoft Visual TrueType (VTT)
tool to store its hinting source data.
TSI1 contains the text of the glyph programs in the form of low-level assembly
code, as well as the 'extra' programs 'fpgm', 'ppgm' (i.e. 'prep'), and 'cvt'.
"""
from . import DefaultTable
from fontTools.misc.loggingTools import LogMixin
from fontTools.misc.textTools import strjoin, tobytes, tostr
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class table_T_S_I__1(LogMixin, DefaultTable.DefaultTable):
extras = {0xFFFA: "ppgm", 0xFFFB: "cvt", 0xFFFC: "reserved", 0xFFFD: "fpgm"}
indextable = "TSI0"
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def decompile(self, data, ttFont):
totalLength = len(data)
indextable = ttFont[self.indextable]
for indices, isExtra in zip(
(indextable.indices, indextable.extra_indices), (False, True)
):
programs = {}
for i, (glyphID, textLength, textOffset) in enumerate(indices):
if isExtra:
name = self.extras[glyphID]
else:
name = ttFont.getGlyphName(glyphID)
if textOffset > totalLength:
self.log.warning("textOffset > totalLength; %r skipped" % name)
continue
if textLength < 0x8000:
# If the length stored in the record is less than 32768, then use
# that as the length of the record.
pass
elif textLength == 0x8000:
# If the length is 32768, compute the actual length as follows:
isLast = i == (len(indices) - 1)
if isLast:
if isExtra:
# For the last "extra" record (the very last record of the
# table), the length is the difference between the total
# length of the TSI1 table and the textOffset of the final
# record.
nextTextOffset = totalLength
else:
# For the last "normal" record (the last record just prior
# to the record containing the "magic number"), the length
# is the difference between the textOffset of the record
# following the "magic number" (0xFFFE) record (i.e. the
# first "extra" record), and the textOffset of the last
# "normal" record.
nextTextOffset = indextable.extra_indices[0][2]
else:
# For all other records with a length of 0x8000, the length is
# the difference between the textOffset of the record in
# question and the textOffset of the next record.
nextTextOffset = indices[i + 1][2]
assert nextTextOffset >= textOffset, "entries not sorted by offset"
if nextTextOffset > totalLength:
self.log.warning(
"nextTextOffset > totalLength; %r truncated" % name
)
nextTextOffset = totalLength
textLength = nextTextOffset - textOffset
else:
from fontTools import ttLib
raise ttLib.TTLibError(
"%r textLength (%d) must not be > 32768" % (name, textLength)
)
text = data[textOffset : textOffset + textLength]
assert len(text) == textLength
text = tostr(text, encoding="utf-8")
if text:
programs[name] = text
if isExtra:
self.extraPrograms = programs
else:
self.glyphPrograms = programs
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def compile(self, ttFont):
if not hasattr(self, "glyphPrograms"):
self.glyphPrograms = {}
self.extraPrograms = {}
data = b""
indextable = ttFont[self.indextable]
glyphNames = ttFont.getGlyphOrder()
indices = []
for i in range(len(glyphNames)):
if len(data) % 2:
data = (
data + b"\015"
) # align on 2-byte boundaries, fill with return chars. Yum.
name = glyphNames[i]
if name in self.glyphPrograms:
text = tobytes(self.glyphPrograms[name], encoding="utf-8")
else:
text = b""
textLength = len(text)
if textLength >= 0x8000:
textLength = 0x8000
indices.append((i, textLength, len(data)))
data = data + text
extra_indices = []
codes = sorted(self.extras.items())
for i in range(len(codes)):
if len(data) % 2:
data = (
data + b"\015"
) # align on 2-byte boundaries, fill with return chars.
code, name = codes[i]
if name in self.extraPrograms:
text = tobytes(self.extraPrograms[name], encoding="utf-8")
else:
text = b""
textLength = len(text)
if textLength >= 0x8000:
textLength = 0x8000
extra_indices.append((code, textLength, len(data)))
data = data + text
indextable.set(indices, extra_indices)
return data
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def toXML(self, writer, ttFont):
names = sorted(self.glyphPrograms.keys())
writer.newline()
for name in names:
text = self.glyphPrograms[name]
if not text:
continue
writer.begintag("glyphProgram", name=name)
writer.newline()
writer.write_noindent(text.replace("\r", "\n"))
writer.newline()
writer.endtag("glyphProgram")
writer.newline()
writer.newline()
extra_names = sorted(self.extraPrograms.keys())
for name in extra_names:
text = self.extraPrograms[name]
if not text:
continue
writer.begintag("extraProgram", name=name)
writer.newline()
writer.write_noindent(text.replace("\r", "\n"))
writer.newline()
writer.endtag("extraProgram")
writer.newline()
writer.newline()
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def fromXML(self, name, attrs, content, ttFont):
if not hasattr(self, "glyphPrograms"):
self.glyphPrograms = {}
self.extraPrograms = {}
lines = strjoin(content).replace("\r", "\n").split("\n")
text = "\r".join(lines[1:-1])
if name == "glyphProgram":
self.glyphPrograms[attrs["name"]] = text
elif name == "extraProgram":
self.extraPrograms[attrs["name"]] = text