isPairPos and isSinglePos are mutually exclusive and isSinglePos is only defined if isPairPos is False
so it is safe to use it in 'else' or 'elif' branches (logical expressions short-circuit)
When a SinglePost lookup is compiled, pretty much all compilers do some compression by combining similar ValueRecords into a single subtable. This compression produces different lengths of the list of subtables between source fonts. The original code required that all SinglePos lookups have the same subtables, often doesn't work.
I fixed this in varLib.merger.py by first flattening a SinglePos lookup to a single subtable, using the same record format for all records, and then merging the source fonts. After the merge is complete, I call fontTools.otlLib.builder.buildSinglePos() to rebuild the lookup subtables.
The code was setting GlyphClassDef.classDefs for the base font to an
empty dict then reading it from all fonts. It accidentally works when
creating variable fonts because the GlyphClassDef of the other fonts
will be used, but when mutating there is only one font.
Fix by reading the glyph classes before assigning to an empty dict.
Just such that their existing .Format is preserved, as that is written out
to the XML file, and would break the test suite if not there.
Stupid to write Coverage Format to XML. Oh well...
VariationMerger is updated such that it accepts None list members
in .mergeThings, and switches to correct sub-model. This means,
it technically supports more than just a few masters missing GPOS.
This allows for some within-GPOS differences to also be handled,
though that's not well-studied or complete.
Part of https://github.com/googlei18n/fontmake/issues/88
Part of https://github.com/fonttools/fonttools/issues/1355
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
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.
