diff options
Diffstat (limited to 'lib/lettering/font_variant.py')
| -rw-r--r-- | lib/lettering/font_variant.py | 90 |
1 files changed, 89 insertions, 1 deletions
diff --git a/lib/lettering/font_variant.py b/lib/lettering/font_variant.py index baf7c09f..5bedaa87 100644 --- a/lib/lettering/font_variant.py +++ b/lib/lettering/font_variant.py @@ -5,6 +5,7 @@ import os from collections import defaultdict +from unicodedata import normalize import inkex @@ -73,7 +74,7 @@ class FontVariant(object): for layer in glyph_layers: self._clean_group(layer) layer.attrib[INKSCAPE_LABEL] = layer.attrib[INKSCAPE_LABEL].replace("GlyphLayer-", "", 1) - glyph_name = layer.attrib[INKSCAPE_LABEL] + glyph_name = normalize('NFKC', layer.attrib[INKSCAPE_LABEL]) try: self.glyphs[glyph_name] = Glyph(layer) except (AttributeError, ValueError): @@ -134,6 +135,93 @@ class FontVariant(object): return svg + def glyphs_start_with(self, character): + glyph_selection = [glyph_name for glyph_name, glyph_layer in self.glyphs.items() if glyph_name.startswith(character)] + return sorted(glyph_selection, key=lambda glyph: (len(glyph.split('.')[0]), len(glyph)), reverse=True) + + def isbinding(self, character): + # after a non binding letter a letter can only be in isol or fina shape. + # binding glyph only have two shapes, isol and fina + non_binding_char = ['ا', 'أ', 'ﺇ', 'آ', 'د', 'ذ', 'ر', 'ز', 'و'] + normalized_non_binding_char = [normalize('NFKC', letter) for letter in non_binding_char] + return not (character in normalized_non_binding_char) + + def ispunctuation(self, character): + # punctuation sign are not considered as part of the word. They onnly have one shape + punctuation_signs = ['؟', '،', '.', ',', ';', '.', '!', ':', '؛'] + normalized_punctuation_signs = [normalize('NFKC', letter) for letter in punctuation_signs] + return (character in normalized_punctuation_signs) + + def get_glyph(self, character, word): + """ + Returns the glyph for the given character, searching for combined glyphs first + This expects glyph annotations to be within the given word, for example: a.init + + Returns glyph node and length of the glyph name + """ + glyph_selection = self.glyphs_start_with(character) + for glyph in glyph_selection: + if word.startswith(glyph): + return self.glyphs[glyph], len(glyph) + return self.glyphs.get(self.default_glyph, None), 1 + + def get_next_glyph_shape(self, word, starting, ending, previous_is_binding): + # in arabic each letter (or ligature) may have up to 4 different shapes, hence 4 glyphs + # this computes the shape of the glyph that represents word[starting:ending+1] + + # punctuation is not really part of the word + # they may appear at begining or end of words + # computes where the actual word begins and ends up + last_char_index = len(word)-1 + first_char_index = 0 + + while self.ispunctuation(word[last_char_index]): + last_char_index = last_char_index - 1 + while self.ispunctuation(word[first_char_index]): + first_char_index = first_char_index + 1 + + # first glyph is eithher isol or init depending wether it is also the last glyph of the actual word + if starting == first_char_index: + if not self.isbinding(word[ending]) or len(word) == 1: + shape = 'isol' + else: + shape = 'init' + # last glyph is final if previous is binding, isol otherwise + # a non binding glyph behaves like the last glyph + elif ending == last_char_index or not self.isbinding(word[ending]): + if previous_is_binding: + shape = 'fina' + else: + shape = 'isol' + # in the middle of the actual word, the shape of a glyph is medi if previous glyph is bendinng, init otherwise + elif previous_is_binding: + shape = 'medi' + else: + shape = 'init' + + return shape + + def get_next_glyph(self, word, i, previous_is_binding): + # search for the glyph of word that starts at i,taking into acount the previous glyph binding status + + # find all the glyphs in tthe font that start with first letter of the glyph + glyph_selection = self.glyphs_start_with(word[i]) + + # find the longest glyph that match + for glyph in glyph_selection: + glyph_name = glyph.split('.') + if len(glyph_name) == 2 and glyph_name[1] in ['isol', 'init', 'medi', 'fina']: + is_binding = self.isbinding(glyph_name[0][-1]) + if len(word) < i + len(glyph_name[0]): + continue + shape = self.get_next_glyph_shape(word, i, i + len(glyph_name[0]) - 1, previous_is_binding) + if glyph_name[1] == shape and word[i:].startswith(glyph_name[0]): + return self.glyphs[glyph], len(glyph_name[0]), is_binding + elif word[i:].startswith(glyph): + return self.glyphs[glyph], len(glyph), True + # nothing was found + return self.glyphs.get(self.default_glyph, None), 1, True + def __getitem__(self, character): if character in self.glyphs: return self.glyphs[character] |