Added interpolation of glyph advance width, from HVAR/hmtx, and derivation of new LSB.
Updated tests to match.
Needed to cherrypick from another branch an update for psCharstrings to allow the CFFSubr.draw() method to work.
varLib.py. restore import of 'fontTools.misc.py23 import *'
varStore.py. Rename 'applyScalar' to 'interpolateFromDeltasAndScalars', and refactor common code with __git__item to a static method.
mutator.py. Update to reflect function name change to interpolateFromDeltasAndScalars. Changed some logic from one line to several lines for readability, and i to avoid flake8 warnings about line too long.
this is the mapping between the half of each percentage intervals and
the associated usWidthClass:
{56.25: 1,
68.75: 2,
81.25: 3,
93.75: 4,
106.25: 5,
118.75: 6,
137.5: 7,
175.0: 8}
Notice how wdth=80 (in the adjusted test case) will fall in width class
3, instead of 4, because it is < 81.25, thus closer to the nominal 75
than to 87.5.
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.
Cleans up GDEF varstore as well.
What's left:
- In none of the varLib.merger Mergers we handle the CaretValueFormat3. That should be done,
even though no one uses this,
- GPOS/GSUB FeatureVariations are not applied. Shouldn't be hard.
- 'rvrn' should be folded into 'ccmp' or some other default feature.
Towards addressing https://github.com/fonttools/fonttools/issues/1070
The new instantiateVariableFont function takes a variable TTFont and a
dictionary of axes locations and returns a static TTFont instance.
The current code modifies the varfont in-place. To adapt it for
generating multiple instances from the same varfont, for now I simply
resorted to making a copy (can be optionally disabled by setting
inplace=True).
Also, replaced print() with log.info().
When varLib was updated for avar table, this was not. Share code such
that they don't get out of sync again. All of this to be made into
proper API some time...
