diff options
| -rw-r--r-- | lib/lettering/kerning.py | 64 |
1 files changed, 53 insertions, 11 deletions
diff --git a/lib/lettering/kerning.py b/lib/lettering/kerning.py index 6380f1a6..5596ce8a 100644 --- a/lib/lettering/kerning.py +++ b/lib/lettering/kerning.py @@ -28,26 +28,68 @@ class FontKerning(object): def hkern(self): xpath = ".//svg:hkern[(@u1 or @g1) and (@u1 or @g1) and @k]/@*[contains(name(), '1') or contains(name(), '2') or name()='k']" hkern = self.svg.xpath(xpath, namespaces=NSS) - for index, glyph in enumerate(hkern): + + # the kerning list now contains the kerning values as a list where every first value contains the first letter(s), + # every second value contains the second letter(s) and every third value contains the kerning + u_first = [k for k in hkern[0::3]] + u_second = [k for k in hkern[1::3]] + k = [int(x) for x in hkern[2::3]] + + # sometimes a font file contains conflicting kerning value for a letter pair + # in this case the value which is specified as a single pair overrules the one specified in a list of letters + # therefore we want to sort our list by length of the letter values + kern_list = list(zip(u_first, u_second, k)) + kern_list.sort(key=lambda x: len(x[0] + x[1]), reverse=True) + + for index, kerning in enumerate(kern_list): + first, second, key = kerning # fontTools.agl will import fontTools.misc.py23 which will output a deprecation warning # ignore the warning for now - until the library fixed it if index == 0: import warnings with warnings.catch_warnings(): warnings.simplefilter("ignore") + global toUnicode from fontTools.agl import toUnicode - if len(glyph) > 1 and not (index + 1) % 3 == 0: - glyph_names = glyph.split(",") - # the glyph name is written in various languages, second is english. Let's look it up. - if len(glyph_names) == 1: - hkern[index] = toUnicode(glyph) - else: - hkern[index] = toUnicode(glyph_names[1]) - k = [int(x) for x in hkern[2::3]] - u = [k + v for k, v in zip(hkern[0::3], hkern[1::3])] - hkern = dict(zip(u, k)) + first = self.split_glyph_list(first) + second = self.split_glyph_list(second) + kern_list[index] = (first, second, key) + + hkern = {} + for first, second, key in kern_list: + for f in first: + for s in second: + hkern[f+s] = key return hkern + def split_glyph_list(self, glyph): + glyphs = [] + if len(glyph) > 1: + # glyph names need to be converted to unicode + # we need to take into account, that there can be more than one first/second letter in the very same hkern element + # in this case they will be commas separated and each first letter needs to be combined with each next letter + # e.g. <hkern g1="A,Agrave,Aacute,Acircumflex,Atilde,Adieresis,Amacron,Abreve,Aogonek" g2="T,Tcaron" k="5" /> + glyph_names = glyph.split(",") + for glyph_name in glyph_names: + # each glyph can have additional special markers, e.g. o.cmp + # toUnicode will not respect those and convert them to a simple letter + # this behaviour will generate a wrong spacing for this letter. + # Let's make sure to also transfer the separators and extensions to our json file + separators = [".", "_"] + used_separator = False + for separator in separators: + glyph_with_separator = glyph_name.split(separator) + if len(glyph_with_separator) == 2: + glyphs.append("%s%s%s" % (toUnicode(glyph_with_separator[0]), separator, glyph_with_separator[1])) + used_separator = True + continue + # there is no extra separator + if not used_separator: + glyphs.append(toUnicode(glyph_name)) + else: + glyphs.append(glyph) + return glyphs + # the space character def word_spacing(self): xpath = "string(.//svg:glyph[@glyph-name='space'][1]/@*[name()='horiz-adv-x'])" |