1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
|
"""
Common functionality between the PDF and PS backends.
"""
from io import BytesIO
import functools
import logging
from fontTools import subset
import matplotlib as mpl
from .. import font_manager, ft2font
from .._afm import AFM
from ..backend_bases import RendererBase
@functools.lru_cache(50)
def _cached_get_afm_from_fname(fname):
with open(fname, "rb") as fh:
return AFM(fh)
def get_glyphs_subset(fontfile, characters):
"""
Subset a TTF font
Reads the named fontfile and restricts the font to the characters.
Parameters
----------
fontfile : str
Path to the font file
characters : str
Continuous set of characters to include in subset
Returns
-------
fontTools.ttLib.ttFont.TTFont
An open font object representing the subset, which needs to
be closed by the caller.
"""
options = subset.Options(glyph_names=True, recommended_glyphs=True)
# Prevent subsetting extra tables.
options.drop_tables += [
'FFTM', # FontForge Timestamp.
'PfEd', # FontForge personal table.
'BDF', # X11 BDF header.
'meta', # Metadata stores design/supported languages (meaningless for subsets).
'MERG', # Merge Table.
'TSIV', # Microsoft Visual TrueType extension.
'Zapf', # Information about the individual glyphs in the font.
'bdat', # The bitmap data table.
'bloc', # The bitmap location table.
'cidg', # CID to Glyph ID table (Apple Advanced Typography).
'fdsc', # The font descriptors table.
'feat', # Feature name table (Apple Advanced Typography).
'fmtx', # The Font Metrics Table.
'fond', # Data-fork font information (Apple Advanced Typography).
'just', # The justification table (Apple Advanced Typography).
'kerx', # An extended kerning table (Apple Advanced Typography).
'ltag', # Language Tag.
'morx', # Extended Glyph Metamorphosis Table.
'trak', # Tracking table.
'xref', # The cross-reference table (some Apple font tooling information).
]
# if fontfile is a ttc, specify font number
if fontfile.endswith(".ttc"):
options.font_number = 0
font = subset.load_font(fontfile, options)
subsetter = subset.Subsetter(options=options)
subsetter.populate(text=characters)
subsetter.subset(font)
return font
def font_as_file(font):
"""
Convert a TTFont object into a file-like object.
Parameters
----------
font : fontTools.ttLib.ttFont.TTFont
A font object
Returns
-------
BytesIO
A file object with the font saved into it
"""
fh = BytesIO()
font.save(fh, reorderTables=False)
return fh
class CharacterTracker:
"""
Helper for font subsetting by the pdf and ps backends.
Maintains a mapping of font paths to the set of character codepoints that
are being used from that font.
"""
def __init__(self):
self.used = {}
def track(self, font, s):
"""Record that string *s* is being typeset using font *font*."""
char_to_font = font._get_fontmap(s)
for _c, _f in char_to_font.items():
self.used.setdefault(_f.fname, set()).add(ord(_c))
def track_glyph(self, font, glyph):
"""Record that codepoint *glyph* is being typeset using font *font*."""
self.used.setdefault(font.fname, set()).add(glyph)
class RendererPDFPSBase(RendererBase):
# The following attributes must be defined by the subclasses:
# - _afm_font_dir
# - _use_afm_rc_name
def __init__(self, width, height):
super().__init__()
self.width = width
self.height = height
def flipy(self):
# docstring inherited
return False # y increases from bottom to top.
def option_scale_image(self):
# docstring inherited
return True # PDF and PS support arbitrary image scaling.
def option_image_nocomposite(self):
# docstring inherited
# Decide whether to composite image based on rcParam value.
return not mpl.rcParams["image.composite_image"]
def get_canvas_width_height(self):
# docstring inherited
return self.width * 72.0, self.height * 72.0
def get_text_width_height_descent(self, s, prop, ismath):
# docstring inherited
if ismath == "TeX":
return super().get_text_width_height_descent(s, prop, ismath)
elif ismath:
parse = self._text2path.mathtext_parser.parse(s, 72, prop)
return parse.width, parse.height, parse.depth
elif mpl.rcParams[self._use_afm_rc_name]:
font = self._get_font_afm(prop)
l, b, w, h, d = font.get_str_bbox_and_descent(s)
scale = prop.get_size_in_points() / 1000
w *= scale
h *= scale
d *= scale
return w, h, d
else:
font = self._get_font_ttf(prop)
font.set_text(s, 0.0, flags=ft2font.LoadFlags.NO_HINTING)
w, h = font.get_width_height()
d = font.get_descent()
scale = 1 / 64
w *= scale
h *= scale
d *= scale
return w, h, d
def _get_font_afm(self, prop):
fname = font_manager.findfont(
prop, fontext="afm", directory=self._afm_font_dir)
return _cached_get_afm_from_fname(fname)
def _get_font_ttf(self, prop):
fnames = font_manager.fontManager._find_fonts_by_props(prop)
try:
font = font_manager.get_font(fnames)
font.clear()
font.set_size(prop.get_size_in_points(), 72)
return font
except RuntimeError:
logging.getLogger(__name__).warning(
"The PostScript/PDF backend does not currently "
"support the selected font (%s).", fnames)
raise
|
