* a charstring is not guaranteed to end in an operator, so the final bytecodes 11 and 14 can be part of an encoded numeric value; so remove 'return' or 'endchar' at the program level instead of bytescode
* move non-CFF2 test+error to elif clause of earlier isCFF2 test
Fixes the remaining issue from #1451
@bedhad
Address issues raised in #1403
I do think setting the dummy CFF2 PrivateDict nominalWidthX and defaultWidthX to None, which leads to the charstring.width also being None, is a good idea. I originally set them to 0, which produces a charstring width of 0, in order to avoid problems with logic that assumes that the field is good for math. However, I now think that it is better to find errors around charstring type assumptions earlier than later.
"drop_hints()" is actually not wrong - I did look at this when making the changes. For CFF2 charstrings, self.width is always equal to self.private.defaultWidthX, so the width is never inserted. This is because in psCharstrings.py::T2WidthExtractor.popallWidth(), the test "evenOdd ^ (len(args) % 2)" is alway False. Left to myself, I would not change this code. If the CFF2 charstring is correct, there is not a problem. if the CFF2 charstring is not correct, then both in drop_hints() and in T2WidthExtractor.popallWidth(), the logic will stack dump. I did add asserts, but am not totally sure it is worth the extra calls.
Fixed psCharstrings so that calc_bounds will run. I would guess no-one has tried to use a BoundsPen on a CFF2 VF before - thanks to Chris Chapman. It now returns a result only for the default instance.
Fixed bug in subsetting: removed assert that a Subr is not empty after subsetting or de-hinting. CFF2 Charstrings do not have terminal "return' op.
Removed check_program functions. Supporting these requires knowledge of CFF vs CFF2 state, whci is leads to wide-spread diffuse changes. Also, not needed - the endchar/return opcodes are removed when compiling for CFF2.
Removed CFF2Subr class. This was used for CFF2 CharStrings, and allowed avoiding referencing the width fields. I worked around this by providing dummy values for the Private.nominalWidthX and defaultWidthX.
Added a public method PrivateDict.in_cff2.
varStore.py. Commit the correct function references.
psCharstrings.py. Add decompiler class specifically for flattening subroutinized charstrings.
mutator.py. Flatten the subroutinized charstrings, delete the Subrs.
TestCFF2VF.otf, Updated to version with subroutinization. Updated expected ttx output.
by encoding as integers all float values that have no decimal portion.
This optimization is expected to reduce the file size of CFF2 fonts that have intermediate masters.
Related to https://github.com/adobe-type-tools/afdko/issues/444
Many thanks to @cjchapman for the help on the fixed point math
So we now round towards +Infinity in:
- floatToFixed (which fully examplify that quotes from OT spec)
- psCharStrings: when packing floats as fixed 16.16
- t2CharStringPen: when rounding coordinates and advance widths
- subset: when rounding advance widths to compute average
- TupleVariation: rounding gvar deltas
- _g_l_y_f: when rounding coordinates: both in GlyphComponent.{x,y}
and for GlyphCoordinates.toInt()
- _h_m_t_x: for rounding horiz/vert metrics
- varLib: rounding horiz metrics and deltas
I'm also unimpressed by the copy-pasted bounds logic in hhea and vhea,
and the fact that that's coded in there instead of calling a function
on CFF / glyf tables respectively.
This also fixes fonttools/fonttools/issues/1030.
Although the roundtrip is generally possible when a VariationStore is built from source font data using the Superpolator model, it is possible to build region definitions that do not follow this model. Behdad cited the Skia "Q" example, where the tail of the Q is affected by two regions defined as:
min=0 peak=0.5 max=0.51 delta=+10
min=0.49 peak=0.5 max=0.51 delta=-10
We don't need to cast to int when using the round function from py23,
as this is a backport of python3's built-in round and thus it returns
an int when called with a single argument.
* Removed `CFFContext`
* Added `isCFF2` argument to CFFFontSet.decompile/compile, used from
respective ttLib classes
* Index classes get a `isCFF2` argument in constructor (used for
decompiling); must be True/False if `file` argument is not None;
it is stored as self._isCFF2 to support lazy loading
* Removed `TopDictData` class; reuse same `TopDictIndexCompiler` for
both CFF and CFF2
* `CFFWriter` and all `*Compiler` classes get an `isCFF2` argument;
defaults to the parent compiler's `isCFF2` attribute
* Removed `size` argument from `produceItem` method as unused and
useless (`len(data)` is the same)
* psCharStrings: removed useless ByteCodeBase class
* A reference to the TopDict's VarStoreData is passed down to all
the FontDicts' PrivateDict, so it can be used to get the number of
regions while decompiling blend and vsindex operators
See dicussion:
https://github.com/fonttools/fonttools/pull/968#issuecomment-309920007
SimpleCFF2DEcompiler
CFF2CharString
GlobalSubrsIndex2
SubrsIndex2
CharstringIndex2
Working towards using one set of classes for both CFF2 and CFF data.
After 2b2aca1, DictCompiler/Decompiler's `arg_delta` method unconditionally attempts to get the first item to check if it's a list, but this fails with `IndexError` when the value is empty.
```
Traceback (most recent call last):
[...]
File "/Users/cosimolupo/Documents/Github/ufo2ft/Lib/ufo2ft/otfPostProcessor.py", line 15, in __init__
otf.save(stream)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/ttLib/__init__.py", line 219, in save
self._writeTable(tag, writer, done)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/ttLib/__init__.py", line 658, in _writeTable
tabledata = self.getTableData(tag)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/ttLib/__init__.py", line 669, in getTableData
return self.tables[tag].compile(self)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/ttLib/tables/C_F_F_.py", line 20, in compile
self.cff.compile(f, otFont)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/cffLib.py", line 124, in compile
writer.toFile(file)
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/cffLib.py", line 300, in toFile
endPos = pos + item.getDataLength()
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/cffLib.py", line 1858, in getDataLength
return len(self.compile("getDataLength"))
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/cffLib.py", line 1879, in compile
data.append(arghandler(value))
File "/Users/cosimolupo/Documents/Github/fonttools/Lib/fontTools/cffLib.py", line 1910, in arg_delta
val0 = value[0]
IndexError: list index out of range
``
We shall reuse it as base class for the _DehintingT2Decompiler in subset module,
as we need to save the width in order to re-insert it after dropping the hints.
