def removeOverlaps(
font: ttFont.TTFont,
glyphNames: Optional[Iterable[str]] = None,
removeHinting: bool = True,
) -> None:
"""Simplify glyphs in TTFont by merging overlapping contours.
Overlapping components are first decomposed to simple contours, then merged.
Currently this only works with TrueType fonts with 'glyf' table.
Raises NotImplementedError if 'glyf' table is absent.
Note that removing overlaps invalidates the hinting. By default we drop hinting
from all glyphs whether or not overlaps are removed from a given one, as it would
look weird if only some glyphs are left (un)hinted.
Args:
font: input TTFont object, modified in place.
glyphNames: optional iterable of glyph names (str) to remove overlaps from.
By default, all glyphs in the font are processed.
removeHinting (bool): set to False to keep hinting for unmodified glyphs.
"""
try:
glyfTable = font["glyf"]
except KeyError:
raise NotImplementedError(
"removeOverlaps currently only works with TTFs")
hmtxTable = font["hmtx"]
# wraps the underlying glyf Glyphs, takes care of interfacing with drawing pens
glyphSet = font.getGlyphSet()
if glyphNames is None:
glyphNames = font.getGlyphOrder()
# process all simple glyphs first, then composites with increasing component depth,
# so that by the time we test for component intersections the respective base glyphs
# have already been simplified
glyphNames = sorted(
glyphNames,
key=lambda name: (
glyfTable[name].getCompositeMaxpValues(glyfTable).maxComponentDepth
if glyfTable[name].isComposite() else 0,
name,
),
)
modified = set()
for glyphName in glyphNames:
if removeTTGlyphOverlaps(glyphName, glyphSet, glyfTable, hmtxTable,
removeHinting):
modified.add(glyphName)
log.debug("Removed overlaps for %s glyphs:\n%s", len(modified),
" ".join(modified))
def ttfont_glyph_to_skia_path(glyph_name: str, tt_font: ttFont.TTFont) -> pathops.Path:
"""
Converts fontTools.ttLib.TTFont glyph to a pathops.Path object
by glyph name. During this conversion, all composite paths are
decomposed.
"""
glyf_table = tt_font["glyf"]
glyph_set: ttFont._TTGlyphSet = tt_font.getGlyphSet()
tt_glyph = glyf_table[glyph_name]
skia_path = pathops.Path()
skia_path_pen = skia_path.getPen()
if tt_glyph.isComposite():
decompose_pen = DecomposingRecordingPen(glyph_set)
glyph_set[glyph_name].draw(decompose_pen)
decompose_pen.replay(skia_path_pen)
return skia_path
else:
glyph_set[glyph_name].draw(skia_path_pen)
return skia_path