"""
A module for finding, managing, and using fonts across platforms.
This module provides a single `FontManager` instance, ``fontManager``, that can
be shared across backends and platforms. The `findfont`
function returns the best TrueType (TTF) font file in the local or
system font path that matches the specified `FontProperties`
instance. The `FontManager` also handles Adobe Font Metrics
(AFM) font files for use by the PostScript backend.
The design is based on the `W3C Cascading Style Sheet, Level 1 (CSS1)
font specification <http://www.w3.org/TR/1998/REC-CSS2-19980512/>`_.
Future versions may implement the Level 2 or 2.1 specifications.
"""
# KNOWN ISSUES
#
# - documentation
# - font variant is untested
# - font stretch is incomplete
# - font size is incomplete
# - default font algorithm needs improvement and testing
# - setWeights function needs improvement
# - 'light' is an invalid weight value, remove it.
from base64 import b64encode
from collections import namedtuple
import copy
import dataclasses
from functools import lru_cache
from io import BytesIO
import json
import logging
from numbers import Number
import os
from pathlib import Path
import re
import subprocess
import sys
import threading
import matplotlib as mpl
from matplotlib import _api, _afm, cbook, ft2font
from matplotlib._fontconfig_pattern import (
parse_fontconfig_pattern, generate_fontconfig_pattern)
from matplotlib.rcsetup import _validators
_log = logging.getLogger(__name__)
font_scalings = {
'xx-small': 0.579,
'x-small': 0.694,
'small': 0.833,
'medium': 1.0,
'large': 1.200,
'x-large': 1.440,
'xx-large': 1.728,
'larger': 1.2,
'smaller': 0.833,
None: 1.0,
}
stretch_dict = {
'ultra-condensed': 100,
'extra-condensed': 200,
'condensed': 300,
'semi-condensed': 400,
'normal': 500,
'semi-expanded': 600,
'semi-extended': 600,
'expanded': 700,
'extended': 700,
'extra-expanded': 800,
'extra-extended': 800,
'ultra-expanded': 900,
'ultra-extended': 900,
}
weight_dict = {
'ultralight': 100,
'light': 200,
'normal': 400,
'regular': 400,
'book': 400,
'medium': 500,
'roman': 500,
'semibold': 600,
'demibold': 600,
'demi': 600,
'bold': 700,
'heavy': 800,
'extra bold': 800,
'black': 900,
}
_weight_regexes = [
# From fontconfig's FcFreeTypeQueryFaceInternal; not the same as
# weight_dict!
("thin", 100),
("extralight", 200),
("ultralight", 200),
("demilight", 350),
("semilight", 350),
("light", 300), # Needs to come *after* demi/semilight!
("book", 380),
("regular", 400),
("normal", 400),
("medium", 500),
("demibold", 600),
("demi", 600),
("semibold", 600),
("extrabold", 800),
("superbold", 800),
("ultrabold", 800),
("bold", 700), # Needs to come *after* extra/super/ultrabold!
("ultrablack", 1000),
("superblack", 1000),
("extrablack", 1000),
(r"\bultra", 1000),
("black", 900), # Needs to come *after* ultra/super/extrablack!
("heavy", 900),
]
font_family_aliases = {
'serif',
'sans-serif',
'sans serif',
'cursive',
'fantasy',
'monospace',
'sans',
}
_ExceptionProxy = namedtuple('_ExceptionProxy', ['klass', 'message'])
# OS Font paths
try:
_HOME = Path.home()
except Exception: # Exceptions thrown by home() are not specified...
_HOME = Path(os.devnull) # Just an arbitrary path with no children.
MSFolders = \
r'Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders'
MSFontDirectories = [
r'SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts',
r'SOFTWARE\Microsoft\Windows\CurrentVersion\Fonts']
MSUserFontDirectories = [
str(_HOME / 'AppData/Local/Microsoft/Windows/Fonts'),
str(_HOME / 'AppData/Roaming/Microsoft/Windows/Fonts'),
]
X11FontDirectories = [
# an old standard installation point
"/usr/X11R6/lib/X11/fonts/TTF/",
"/usr/X11/lib/X11/fonts",
# here is the new standard location for fonts
"/usr/share/fonts/",
# documented as a good place to install new fonts
"/usr/local/share/fonts/",
# common application, not really useful
"/usr/lib/openoffice/share/fonts/truetype/",
# user fonts
str((Path(os.environ.get('XDG_DATA_HOME') or _HOME / ".local/share"))
/ "fonts"),
str(_HOME / ".fonts"),
]
OSXFontDirectories = [
"/Library/Fonts/",
"/Network/Library/Fonts/",
"/System/Library/Fonts/",
# fonts installed via MacPorts
"/opt/local/share/fonts",
# user fonts
str(_HOME / "Library/Fonts"),
]
def get_fontext_synonyms(fontext):
"""
Return a list of file extensions that are synonyms for
the given file extension *fileext*.
"""
return {
'afm': ['afm'],
'otf': ['otf', 'ttc', 'ttf'],
'ttc': ['otf', 'ttc', 'ttf'],
'ttf': ['otf', 'ttc', 'ttf'],
}[fontext]
def list_fonts(directory, extensions):
"""
Return a list of all fonts matching any of the extensions, found
recursively under the directory.
"""
extensions = ["." + ext for ext in extensions]
return [os.path.join(dirpath, filename)
# os.walk ignores access errors, unlike Path.glob.
for dirpath, _, filenames in os.walk(directory)
for filename in filenames
if Path(filename).suffix.lower() in extensions]
def win32FontDirectory():
r"""
Return the user-specified font directory for Win32. This is
looked up from the registry key ::
\\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders\Fonts
If the key is not found, ``%WINDIR%\Fonts`` will be returned.
"""
import winreg
try:
with winreg.OpenKey(winreg.HKEY_CURRENT_USER, MSFolders) as user:
return winreg.QueryValueEx(user, 'Fonts')[0]
except OSError:
return os.path.join(os.environ['WINDIR'], 'Fonts')
def _get_win32_installed_fonts():
"""List the font paths known to the Windows registry."""
import winreg
items = set()
# Search and resolve fonts listed in the registry.
for domain, base_dirs in [
(winreg.HKEY_LOCAL_MACHINE, [win32FontDirectory()]), # System.
(winreg.HKEY_CURRENT_USER, MSUserFontDirectories), # User.
]:
for base_dir in base_dirs:
for reg_path in MSFontDirectories:
try:
with winreg.OpenKey(domain, reg_path) as local:
for j in range(winreg.QueryInfoKey(local)[1]):
# value may contain the filename of the font or its
# absolute path.
key, value, tp = winreg.EnumValue(local, j)
if not isinstance(value, str):
continue
try:
# If value contains already an absolute path,
# then it is not changed further.
path = Path(base_dir, value).resolve()
except RuntimeError:
# Don't fail with invalid entries.
continue
items.add(path)
except (OSError, MemoryError):
continue
return items
@lru_cache()
def _get_fontconfig_fonts():
"""Cache and list the font paths known to ``fc-list``."""
try:
if b'--format' not in subprocess.check_output(['fc-list', '--help']):
_log.warning( # fontconfig 2.7 implemented --format.
'Matplotlib needs fontconfig>=2.7 to query system fonts.')
return []
out = subprocess.check_output(['fc-list', '--format=%{file}\\n'])
except (OSError, subprocess.CalledProcessError):
return []
return [Path(os.fsdecode(fname)) for fname in out.split(b'\n')]
def findSystemFonts(fontpaths=None, fontext='ttf'):
"""
Search for fonts in the specified font paths. If no paths are
given, will use a standard set of system paths, as well as the
list of fonts tracked by fontconfig if fontconfig is installed and
available. A list of TrueType fonts are returned by default with
AFM fonts as an option.
"""
fontfiles = set()
fontexts = get_fontext_synonyms(fontext)
if fontpaths is None:
if sys.platform == 'win32':
installed_fonts = _get_win32_installed_fonts()
fontpaths = []
else:
installed_fonts = _get_fontconfig_fonts()
if sys.platform == 'darwin':
fontpaths = [*X11FontDirectories, *OSXFontDirectories]
else:
fontpaths = X11FontDirectories
fontfiles.update(str(path) for path in installed_fonts
if path.suffix.lower()[1:] in fontexts)
elif isinstance(fontpaths, str):
fontpaths = [fontpaths]
for path in fontpaths:
fontfiles.update(map(os.path.abspath, list_fonts(path, fontexts)))
return [fname for fname in fontfiles if os.path.exists(fname)]
def _fontentry_helper_repr_png(fontent):
from matplotlib.figure import Figure # Circular import.
fig = Figure()
font_path = Path(fontent.fname) if fontent.fname != '' else None
fig.text(0, 0, fontent.name, font=font_path)
with BytesIO() as buf:
fig.savefig(buf, bbox_inches='tight', transparent=True)
return buf.getvalue()
def _fontentry_helper_repr_html(fontent):
png_stream = _fontentry_helper_repr_png(fontent)
png_b64 = b64encode(png_stream).decode()
return f"<img src=\"data:image/png;base64, {png_b64}\" />"
FontEntry = dataclasses.make_dataclass(
'FontEntry', [
('fname', str, dataclasses.field(default='')),
('name', str, dataclasses.field(default='')),
('style', str, dataclasses.field(default='normal')),
('variant', str, dataclasses.field(default='normal')),
('weight', str, dataclasses.field(default='normal')),
('stretch', str, dataclasses.field(default='normal')),
('size', str, dataclasses.field(default='medium')),
],
namespace={
'__doc__': """
A class for storing Font properties.
It is used when populating the font lookup dictionary.
""",
'_repr_html_': lambda self: _fontentry_helper_repr_html(self),
'_repr_png_': lambda self: _fontentry_helper_repr_png(self),
}
)
def ttfFontProperty(font):
"""
Extract information from a TrueType font file.
Parameters
----------
font : `.FT2Font`
The TrueType font file from which information will be extracted.
Returns
-------
`FontEntry`
The extracted font properties.
"""
name = font.family_name
# Styles are: italic, oblique, and normal (default)
sfnt = font.get_sfnt()
mac_key = (1, # platform: macintosh
0, # id: roman
0) # langid: english
ms_key = (3, # platform: microsoft
1, # id: unicode_cs
0x0409) # langid: english_united_states
# These tables are actually mac_roman-encoded, but mac_roman support may be
# missing in some alternative Python implementations and we are only going
# to look for ASCII substrings, where any ASCII-compatible encoding works
# - or big-endian UTF-16, since important Microsoft fonts use that.
sfnt2 = (sfnt.get((*mac_key, 2), b'').decode('latin-1').lower() or
sfnt.get((*ms_key, 2), b'').decode('utf_16_be').lower())
sfnt4 = (sfnt.get((*mac_key, 4), b'').decode('latin-1').lower() or
sfnt.get((*ms_key, 4), b'').decode('utf_16_be').lower())
if sfnt4.find('oblique') >= 0:
style = 'oblique'
elif sfnt4.find('italic') >= 0:
style = 'italic'
elif sfnt2.find('regular') >= 0:
style = 'normal'
elif font.style_flags & ft2font.ITALIC:
style = 'italic'
else:
style = 'normal'
# Variants are: small-caps and normal (default)
# !!!! Untested
if name.lower() in ['capitals', 'small-caps']:
variant = 'small-caps'
else:
variant = 'normal'
# The weight-guessing algorithm is directly translated from fontconfig
# 2.13.1's FcFreeTypeQueryFaceInternal (fcfreetype.c).
wws_subfamily = 22
typographic_subfamily = 16
font_subfamily = 2
styles = [
sfnt.get((*mac_key, wws_subfamily), b'').decode('latin-1'),
sfnt.get((*mac_key, typographic_subfamily), b'').decode('latin-1'),
sfnt.get((*mac_key, font_subfamily), b'').decode('latin-1'),
sfnt.get((*ms_key, wws_subfamily), b'').decode('utf-16-be'),
sfnt.get((*ms_key, typographic_subfamily), b'').decode('utf-16-be'),
sfnt.get((*ms_key, font_subfamily), b'').decode('utf-16-be'),
]
styles = [*filter(None, styles)] or [font.style_name]
def get_weight(): # From fontconfig's FcFreeTypeQueryFaceInternal.
# OS/2 table weight.
os2 = font.get_sfnt_table("OS/2")
if os2 and os2["version"] != 0xffff:
return os2["usWeightClass"]
# PostScript font info weight.
try:
ps_font_info_weight = (
font.get_ps_font_info()["weight"].replace(" ", "") or "")
except ValueError:
pass
else:
for regex, weight in _weight_regexes:
if re.fullmatch(regex, ps_font_info_weight, re.I):
return weight
# Style name weight.
for style in styles:
style = style.replace(" ", "")
for regex, weight in _weight_regexes:
if re.search(regex, style, re.I):
return weight
if font.style_flags & ft2font.BOLD:
return 700 # "bold"
return 500 # "medium", not "regular"!
weight = int(get_weight())
# Stretch can be absolute and relative
# Absolute stretches are: ultra-condensed, extra-condensed, condensed,
# semi-condensed, normal, semi-expanded, expanded, extra-expanded,
# and ultra-expanded.
# Relative stretches are: wider, narrower
# Child value is: inherit
if any(word in sfnt4 for word in ['narrow', 'condensed', 'cond']):
stretch = 'condensed'
elif 'demi cond' in sfnt4:
stretch = 'semi-condensed'
elif any(word in sfnt4 for word in ['wide', 'expanded', 'extended']):
stretch = 'expanded'
else:
stretch = 'normal'
# Sizes can be absolute and relative.
# Absolute sizes are: xx-small, x-small, small, medium, large, x-large,
# and xx-large.
# Relative sizes are: larger, smaller
# Length value is an absolute font size, e.g., 12pt
# Percentage values are in 'em's. Most robust specification.
if not font.scalable:
raise NotImplementedError("Non-scalable fonts are not supported")
size = 'scalable'
return FontEntry(font.fname, name, style, variant, weight, stretch, size)
def afmFontProperty(fontpath, font):
"""
Extract information from an AFM font file.
Parameters
----------
font : AFM
The AFM font file from which information will be extracted.
Returns
-------
`FontEntry`
The extracted font properties.
"""
name = font.get_familyname()
fontname = font.get_fontname().lower()
# Styles are: italic, oblique, and normal (default)
if font.get_angle() != 0 or 'italic' in name.lower():
style = 'italic'
elif 'oblique' in name.lower():
style = 'oblique'
else:
style = 'normal'
# Variants are: small-caps and normal (default)
# !!!! Untested
if name.lower() in ['capitals', 'small-caps']:
variant = 'small-caps'
else:
variant = 'normal'
weight = font.get_weight().lower()
if weight not in weight_dict:
weight = 'normal'
# Stretch can be absolute and relative
# Absolute stretches are: ultra-condensed, extra-condensed, condensed,
# semi-condensed, normal, semi-expanded, expanded, extra-expanded,
# and ultra-expanded.
# Relative stretches are: wider, narrower
# Child value is: inherit
if 'demi cond' in fontname:
stretch = 'semi-condensed'
elif any(word in fontname for word in ['narrow', 'cond']):
stretch = 'condensed'
elif any(word in fontname for word in ['wide', 'expanded', 'extended']):
stretch = 'expanded'
else:
stretch = 'normal'
# Sizes can be absolute and relative.
# Absolute sizes are: xx-small, x-small, small, medium, large, x-large,
# and xx-large.
# Relative sizes are: larger, smaller
# Length value is an absolute font size, e.g., 12pt
# Percentage values are in 'em's. Most robust specification.
# All AFM fonts are apparently scalable.
size = 'scalable'
return FontEntry(fontpath, name, style, variant, weight, stretch, size)
class FontProperties:
"""
A class for storing and manipulating font properties.
The font properties are the six properties described in the
`W3C Cascading Style Sheet, Level 1
<http://www.w3.org/TR/1998/REC-CSS2-19980512/>`_ font
specification and *math_fontfamily* for math fonts:
- family: A list of font names in decreasing order of priority.
The items may include a generic font family name, either 'sans-serif',
'serif', 'cursive', 'fantasy', or 'monospace'. In that case, the actual
font to be used will be looked up from the associated rcParam during the
search process in `.findfont`. Default: :rc:`font.family`
- style: Either 'normal', 'italic' or 'oblique'.
Default: :rc:`font.style`
- variant: Either 'normal' or 'small-caps'.
Default: :rc:`font.variant`
- stretch: A numeric value in the range 0-1000 or one of
'ultra-condensed', 'extra-condensed', 'condensed',
'semi-condensed', 'normal', 'semi-expanded', 'expanded',
'extra-expanded' or 'ultra-expanded'. Default: :rc:`font.stretch`
- weight: A numeric value in the range 0-1000 or one of
'ultralight', 'light', 'normal', 'regular', 'book', 'medium',
'roman', 'semibold', 'demibold', 'demi', 'bold', 'heavy',
'extra bold', 'black'. Default: :rc:`font.weight`
- size: Either a relative value of 'xx-small', 'x-small',
'small', 'medium', 'large', 'x-large', 'xx-large' or an
absolute font size, e.g., 10. Default: :rc:`font.size`
- math_fontfamily: The family of fonts used to render math text.
Supported values are: 'dejavusans', 'dejavuserif', 'cm',
'stix', 'stixsans' and 'custom'. Default: :rc:`mathtext.fontset`
Alternatively, a font may be specified using the absolute path to a font
file, by using the *fname* kwarg. However, in this case, it is typically
simpler to just pass the path (as a `pathlib.Path`, not a `str`) to the
*font* kwarg of the `.Text` object.
The preferred usage of font sizes is to use the relative values,
e.g., 'large', instead of absolute font sizes, e.g., 12. This
approach allows all text sizes to be made larger or smaller based
on the font manager's default font size.
This class will also accept a fontconfig_ pattern_, if it is the only
argument provided. This support does not depend on fontconfig; we are
merely borrowing its pattern syntax for use here.
.. _fontconfig: https://www.freedesktop.org/wiki/Software/fontconfig/
.. _pattern:
https://www.freedesktop.org/software/fontconfig/fontconfig-user.html
Note that Matplotlib's internal font manager and fontconfig use a
different algorithm to lookup fonts, so the results of the same pattern
may be different in Matplotlib than in other applications that use
fontconfig.
"""
def __init__(self, family=None, style=None, variant=None, weight=None,
stretch=None, size=None,
fname=None, # if set, it's a hardcoded filename to use
math_fontfamily=None):
self.set_family(family)
self.set_style(style)
self.set_variant(variant)
self.set_weight(weight)
self.set_stretch(stretch)
self.set_file(fname)
self.set_size(size)
self.set_math_fontfamily(math_fontfamily)
# Treat family as a fontconfig pattern if it is the only parameter
# provided. Even in that case, call the other setters first to set
# attributes not specified by the pattern to the rcParams defaults.
if (isinstance(family, str)
and style is None and variant is None and weight is None
and stretch is None and size is None and fname is None):
self.set_fontconfig_pattern(family)
@classmethod
def _from_any(cls, arg):
"""
Generic constructor which can build a `.FontProperties` from any of the
following:
- a `.FontProperties`: it is passed through as is;
- `None`: a `.FontProperties` using rc values is used;
- an `os.PathLike`: it is used as path to the font file;
- a `str`: it is parsed as a fontconfig pattern;
- a `dict`: it is passed as ``**kwargs`` to `.FontProperties`.
"""
if isinstance(arg, cls):
return arg
elif arg is None:
return cls()
elif isinstance(arg, os.PathLike):
return cls(fname=arg)
elif isinstance(arg, str):
return cls(arg)
else:
return cls(**arg)
def __hash__(self):
l = (tuple(self.get_family()),
self.get_slant(),
self.get_variant(),
self.get_weight(),
self.get_stretch(),
self.get_size(),
self.get_file(),
self.get_math_fontfamily())
return hash(l)
def __eq__(self, other):
return hash(self) == hash(other)
def __str__(self):
return self.get_fontconfig_pattern()
def get_family(self):
"""
Return a list of individual font family names or generic family names.
The font families or generic font families (which will be resolved
from their respective rcParams when searching for a matching font) in
the order of preference.
"""
return self._family
def get_name(self):
"""
Return the name of the font that best matches the font properties.
"""
return get_font(findfont(self)).family_name
def get_style(self):
"""
Return the font style. Values are: 'normal', 'italic' or 'oblique'.
"""
return self._slant
def get_variant(self):
"""
Return the font variant. Values are: 'normal' or 'small-caps'.
"""
return self._variant
def get_weight(self):
"""
Set the font weight. Options are: A numeric value in the
range 0-1000 or one of 'light', 'normal', 'regular', 'book',
'medium', 'roman', 'semibold', 'demibold', 'demi', 'bold',
'heavy', 'extra bold', 'black'
"""
return self._weight
def get_stretch(self):
"""
Return the font stretch or width. Options are: 'ultra-condensed',
'extra-condensed', 'condensed', 'semi-condensed', 'normal',
'semi-expanded', 'expanded', 'extra-expanded', 'ultra-expanded'.
"""
return self._stretch
def get_size(self):
"""
Return the font size.
"""
return self._size
def get_file(self):
"""
Return the filename of the associated font.
"""
return self._file
def get_fontconfig_pattern(self):
"""
Get a fontconfig_ pattern_ suitable for looking up the font as
specified with fontconfig's ``fc-match`` utility.
This support does not depend on fontconfig; we are merely borrowing its
pattern syntax for use here.
"""
return generate_fontconfig_pattern(self)
def set_family(self, family):
"""
Change the font family. Can be either an alias (generic name
is CSS parlance), such as: 'serif', 'sans-serif', 'cursive',
'fantasy', or 'monospace', a real font name or a list of real
font names. Real font names are not supported when
:rc:`text.usetex` is `True`. Default: :rc:`font.family`
"""
if family is None:
family = mpl.rcParams['font.family']
if isinstance(family, str):
family = [family]
self._family = family
def set_style(self, style):
"""
Set the font style.
Parameters
----------
style : {'normal', 'italic', 'oblique'}, default: :rc:`font.style`
"""
if style is None:
style = mpl.rcParams['font.style']
_api.check_in_list(['normal', 'italic', 'oblique'], style=style)
self._slant = style
def set_variant(self, variant):
"""
Set the font variant.
Parameters
----------
variant : {'normal', 'small-caps'}, default: :rc:`font.variant`
"""
if variant is None:
variant = mpl.rcParams['font.variant']
_api.check_in_list(['normal', 'small-caps'], variant=variant)
self._variant = variant
def set_weight(self, weight):
"""
Set the font weight.
Parameters
----------
weight : int or {'ultralight', 'light', 'normal', 'regular', 'book', \
'medium', 'roman', 'semibold', 'demibold', 'demi', 'bold', 'heavy', \
'extra bold', 'black'}, default: :rc:`font.weight`
If int, must be in the range 0-1000.
"""
if weight is None:
weight = mpl.rcParams['font.weight']
if weight in weight_dict:
self._weight = weight
return
try:
weight = int(weight)
except ValueError:
pass
else:
if 0 <= weight <= 1000:
self._weight = weight
return
raise ValueError(f"{weight=} is invalid")
def set_stretch(self, stretch):
"""
Set the font stretch or width.
Parameters
----------
stretch : int or {'ultra-condensed', 'extra-condensed', 'condensed', \
'semi-condensed', 'normal', 'semi-expanded', 'expanded', 'extra-expanded', \
'ultra-expanded'}, default: :rc:`font.stretch`
If int, must be in the range 0-1000.
"""
if stretch is None:
stretch = mpl.rcParams['font.stretch']
if stretch in stretch_dict:
self._stretch = stretch
return
try:
stretch = int(stretch)
except ValueError:
pass
else:
if 0 <= stretch <= 1000:
self._stretch = stretch
return
raise ValueError(f"{stretch=} is invalid")
def set_size(self, size):
"""
Set the font size.
Parameters
----------
size : float or {'xx-small', 'x-small', 'small', 'medium', \
'large', 'x-large', 'xx-large'}, default: :rc:`font.size`
If a float, the font size in points. The string values denote
sizes relative to the default font size.
"""
if size is None:
size = mpl.rcParams['font.size']
try:
size = float(size)
except ValueError:
try:
scale = font_scalings[size]
except KeyError as err:
raise ValueError(
"Size is invalid. Valid font size are "
+ ", ".join(map(str, font_scalings))) from err
else:
size = scale * FontManager.get_default_size()
if size < 1.0:
_log.info('Fontsize %1.2f < 1.0 pt not allowed by FreeType. '
'Setting fontsize = 1 pt', size)
size = 1.0
self._size = size
def set_file(self, file):
"""
Set the filename of the fontfile to use. In this case, all
other properties will be ignored.
"""
self._file = os.fspath(file) if file is not None else None
def set_fontconfig_pattern(self, pattern):
"""
Set the properties by parsing a fontconfig_ *pattern*.
This support does not depend on fontconfig; we are merely borrowing its
pattern syntax for use here.
"""
for key, val in parse_fontconfig_pattern(pattern).items():
if type(val) == list:
getattr(self, "set_" + key)(val[0])
else:
getattr(self, "set_" + key)(val)
def get_math_fontfamily(self):
"""
Return the name of the font family used for math text.
The default font is :rc:`mathtext.fontset`.
"""
return self._math_fontfamily
def set_math_fontfamily(self, fontfamily):
"""
Set the font family for text in math mode.
If not set explicitly, :rc:`mathtext.fontset` will be used.
Parameters
----------
fontfamily : str
The name of the font family.
Available font families are defined in the
:ref:`default matplotlibrc file <customizing-with-matplotlibrc-files>`.
See Also
--------
.text.Text.get_math_fontfamily
"""
if fontfamily is None:
fontfamily = mpl.rcParams['mathtext.fontset']
else:
valid_fonts = _validators['mathtext.fontset'].valid.values()
# _check_in_list() Validates the parameter math_fontfamily as
# if it were passed to rcParams['mathtext.fontset']
_api.check_in_list(valid_fonts, math_fontfamily=fontfamily)
self._math_fontfamily = fontfamily
def copy(self):
"""Return a copy of self."""
return copy.copy(self)
# Aliases
set_name = set_family
get_slant = get_style
set_slant = set_style
get_size_in_points = get_size
class _JSONEncoder(json.JSONEncoder):
def default(self, o):
if isinstance(o, FontManager):
return dict(o.__dict__, __class__='FontManager')
elif isinstance(o, FontEntry):
d = dict(o.__dict__, __class__='FontEntry')
try:
# Cache paths of fonts shipped with Matplotlib relative to the
# Matplotlib data path, which helps in the presence of venvs.
d["fname"] = str(
Path(d["fname"]).relative_to(mpl.get_data_path()))
except ValueError:
pass
return d
else:
return super().default(o)
def _json_decode(o):
cls = o.pop('__class__', None)
if cls is None:
return o
elif cls == 'FontManager':
r = FontManager.__new__(FontManager)
r.__dict__.update(o)
return r
elif cls == 'FontEntry':
r = FontEntry.__new__(FontEntry)
r.__dict__.update(o)
if not os.path.isabs(r.fname):
r.fname = os.path.join(mpl.get_data_path(), r.fname)
return r
else:
raise ValueError("Don't know how to deserialize __class__=%s" % cls)
def json_dump(data, filename):
"""
Dump `FontManager` *data* as JSON to the file named *filename*.
See Also
--------
json_load
Notes
-----
File paths that are children of the Matplotlib data path (typically, fonts
shipped with Matplotlib) are stored relative to that data path (to remain
valid across virtualenvs).
This function temporarily locks the output file to prevent multiple
processes from overwriting one another's output.
"""
with cbook._lock_path(filename), open(filename, 'w') as fh:
try:
json.dump(data, fh, cls=_JSONEncoder, indent=2)
except OSError as e:
_log.warning('Could not save font_manager cache {}'.format(e))
def json_load(filename):
"""
Load a `FontManager` from the JSON file named *filename*.
See Also
--------
json_dump
"""
with open(filename) as fh:
return json.load(fh, object_hook=_json_decode)
class FontManager:
"""
On import, the `FontManager` singleton instance creates a list of ttf and
afm fonts and caches their `FontProperties`. The `FontManager.findfont`
method does a nearest neighbor search to find the font that most closely
matches the specification. If no good enough match is found, the default
font is returned.
"""
# Increment this version number whenever the font cache data
# format or behavior has changed and requires an existing font
# cache files to be rebuilt.
__version__ = 330
def __init__(self, size=None, weight='normal'):
self._version = self.__version__
self.__default_weight = weight
self.default_size = size
# Create list of font paths.
paths = [cbook._get_data_path('fonts', subdir)
for subdir in ['ttf', 'afm', 'pdfcorefonts']]
_log.debug('font search path %s', paths)
self.defaultFamily = {
'ttf': 'DejaVu Sans',
'afm': 'Helvetica'}
self.afmlist = []
self.ttflist = []
# Delay the warning by 5s.
timer = threading.Timer(5, lambda: _log.warning(
'Matplotlib is building the font cache; this may take a moment.'))
timer.start()
try:
for fontext in ["afm", "ttf"]:
for path in [*findSystemFonts(paths, fontext=fontext),
*findSystemFonts(fontext=fontext)]:
try:
self.addfont(path)
except OSError as exc:
_log.info("Failed to open font file %s: %s", path, exc)
except Exception as exc:
_log.info("Failed to extract font properties from %s: "
"%s", path, exc)
finally:
timer.cancel()
def addfont(self, path):
"""
Cache the properties of the font at *path* to make it available to the
`FontManager`. The type of font is inferred from the path suffix.
Parameters
----------
path : str or path-like
"""
# Convert to string in case of a path as
# afmFontProperty and FT2Font expect this
path = os.fsdecode(path)
if Path(path).suffix.lower() == ".afm":
with open(path, "rb") as fh:
font = _afm.AFM(fh)
prop = afmFontProperty(path, font)
self.afmlist.append(prop)
else:
font = ft2font.FT2Font(path)
prop = ttfFontProperty(font)
self.ttflist.append(prop)
self._findfont_cached.cache_clear()
@property
def defaultFont(self):
# Lazily evaluated (findfont then caches the result) to avoid including
# the venv path in the json serialization.
return {ext: self.findfont(family, fontext=ext)
for ext, family in self.defaultFamily.items()}
def get_default_weight(self):
"""
Return the default font weight.
"""
return self.__default_weight
@staticmethod
def get_default_size():
"""
Return the default font size.
"""
return mpl.rcParams['font.size']
def set_default_weight(self, weight):
"""
Set the default font weight. The initial value is 'normal'.
"""
self.__default_weight = weight
@staticmethod
def _expand_aliases(family):
if family in ('sans', 'sans serif'):
family = 'sans-serif'
return mpl.rcParams['font.' + family]
# Each of the scoring functions below should return a value between
# 0.0 (perfect match) and 1.0 (terrible match)
def score_family(self, families, family2):
"""
Return a match score between the list of font families in
*families* and the font family name *family2*.
An exact match at the head of the list returns 0.0.
A match further down the list will return between 0 and 1.
No match will return 1.0.
"""
if not isinstance(families, (list, tuple)):
families = [families]
elif len(families) == 0:
return 1.0
family2 = family2.lower()
step = 1 / len(families)
for i, family1 in enumerate(families):
family1 = family1.lower()
if family1 in font_family_aliases:
options = [*map(str.lower, self._expand_aliases(family1))]
if family2 in options:
idx = options.index(family2)
return (i + (idx / len(options))) * step
elif family1 == family2:
# The score should be weighted by where in the
# list the font was found.
return i * step
return 1.0
def score_style(self, style1, style2):
"""
Return a match score between *style1* and *style2*.
An exact match returns 0.0.
A match between 'italic' and 'oblique' returns 0.1.
No match returns 1.0.
"""
if style1 == style2:
return 0.0
elif (style1 in ('italic', 'oblique')
and style2 in ('italic', 'oblique')):
return 0.1
return 1.0
def score_variant(self, variant1, variant2):
"""
Return a match score between *variant1* and *variant2*.
An exact match returns 0.0, otherwise 1.0.
"""
if variant1 == variant2:
return 0.0
else:
return 1.0
def score_stretch(self, stretch1, stretch2):
"""
Return a match score between *stretch1* and *stretch2*.
The result is the absolute value of the difference between the
CSS numeric values of *stretch1* and *stretch2*, normalized
between 0.0 and 1.0.
"""
try:
stretchval1 = int(stretch1)
except ValueError:
stretchval1 = stretch_dict.get(stretch1, 500)
try:
stretchval2 = int(stretch2)
except ValueError:
stretchval2 = stretch_dict.get(stretch2, 500)
return abs(stretchval1 - stretchval2) / 1000.0
def score_weight(self, weight1, weight2):
"""
Return a match score between *weight1* and *weight2*.
The result is 0.0 if both weight1 and weight 2 are given as strings
and have the same value.
Otherwise, the result is the absolute value of the difference between
the CSS numeric values of *weight1* and *weight2*, normalized between
0.05 and 1.0.
"""
# exact match of the weight names, e.g. weight1 == weight2 == "regular"
if cbook._str_equal(weight1, weight2):
return 0.0
w1 = weight1 if isinstance(weight1, Number) else weight_dict[weight1]
w2 = weight2 if isinstance(weight2, Number) else weight_dict[weight2]
return 0.95 * (abs(w1 - w2) / 1000) + 0.05
def score_size(self, size1, size2):
"""
Return a match score between *size1* and *size2*.
If *size2* (the size specified in the font file) is 'scalable', this
function always returns 0.0, since any font size can be generated.
Otherwise, the result is the absolute distance between *size1* and
*size2*, normalized so that the usual range of font sizes (6pt -
72pt) will lie between 0.0 and 1.0.
"""
if size2 == 'scalable':
return 0.0
# Size value should have already been
try:
sizeval1 = float(size1)
except ValueError:
sizeval1 = self.default_size * font_scalings[size1]
try:
sizeval2 = float(size2)
except ValueError:
return 1.0
return abs(sizeval1 - sizeval2) / 72
def findfont(self, prop, fontext='ttf', directory=None,
fallback_to_default=True, rebuild_if_missing=True):
"""
Find a font that most closely matches the given font properties.
Parameters
----------
prop : str or `~matplotlib.font_manager.FontProperties`
The font properties to search for. This can be either a
`.FontProperties` object or a string defining a
`fontconfig patterns`_.
fontext : {'ttf', 'afm'}, default: 'ttf'
The extension of the font file:
- 'ttf': TrueType and OpenType fonts (.ttf, .ttc, .otf)
- 'afm': Adobe Font Metrics (.afm)
directory : str, optional
If given, only search this directory and its subdirectories.
fallback_to_default : bool
If True, will fall back to the default font family (usually
"DejaVu Sans" or "Helvetica") if the first lookup hard-fails.
rebuild_if_missing : bool
Whether to rebuild the font cache and search again if the first
match appears to point to a nonexisting font (i.e., the font cache
contains outdated entries).
Returns
-------
str
The filename of the best matching font.
Notes
-----
This performs a nearest neighbor search. Each font is given a
similarity score to the target font properties. The first font with
the highest score is returned. If no matches below a certain
threshold are found, the default font (usually DejaVu Sans) is
returned.
The result is cached, so subsequent lookups don't have to
perform the O(n) nearest neighbor search.
See the `W3C Cascading Style Sheet, Level 1
<http://www.w3.org/TR/1998/REC-CSS2-19980512/>`_ documentation
for a description of the font finding algorithm.
.. _fontconfig patterns:
https://www.freedesktop.org/software/fontconfig/fontconfig-user.html
"""
# Pass the relevant rcParams (and the font manager, as `self`) to
# _findfont_cached so to prevent using a stale cache entry after an
# rcParam was changed.
rc_params = tuple(tuple(mpl.rcParams[key]) for key in [
"font.serif", "font.sans-serif", "font.cursive", "font.fantasy",
"font.monospace"])
ret = self._findfont_cached(
prop, fontext, directory, fallback_to_default, rebuild_if_missing,
rc_params)
if isinstance(ret, _ExceptionProxy):
raise ret.klass(ret.message)
return ret
def get_font_names(self):
"""Return the list of available fonts."""
return list(set([font.name for font in self.ttflist]))
def _find_fonts_by_props(self, prop, fontext='ttf', directory=None,
fallback_to_default=True, rebuild_if_missing=True):
"""
Find font families that most closely match the given properties.
Parameters
----------
prop : str or `~matplotlib.font_manager.FontProperties`
The font properties to search for. This can be either a
`.FontProperties` object or a string defining a
`fontconfig patterns`_.
fontext : {'ttf', 'afm'}, default: 'ttf'
The extension of the font file:
- 'ttf': TrueType and OpenType fonts (.ttf, .ttc, .otf)
- 'afm': Adobe Font Metrics (.afm)
directory : str, optional
If given, only search this directory and its subdirectories.
fallback_to_default : bool
If True, will fall back to the default font family (usually
"DejaVu Sans" or "Helvetica") if none of the families were found.
rebuild_if_missing : bool
Whether to rebuild the font cache and search again if the first
match appears to point to a nonexisting font (i.e., the font cache
contains outdated entries).
Returns
-------
list[str]
The paths of the fonts found
Notes
-----
This is an extension/wrapper of the original findfont API, which only
returns a single font for given font properties. Instead, this API
returns a dict containing multiple fonts and their filepaths
which closely match the given font properties. Since this internally
uses the original API, there's no change to the logic of performing the
nearest neighbor search. See `findfont` for more details.
"""
prop = FontProperties._from_any(prop)
fpaths = []
for family in prop.get_family():
cprop = prop.copy()
cprop.set_family(family) # set current prop's family
try:
fpaths.append(
self.findfont(
cprop, fontext, directory,
fallback_to_default=False, # don't fallback to default
rebuild_if_missing=rebuild_if_missing,
)
)
except ValueError:
if family in font_family_aliases:
_log.warning(
"findfont: Generic family %r not found because "
"none of the following families were found: %s",
family, ", ".join(self._expand_aliases(family))
)
else:
_log.warning("findfont: Font family %r not found.", family)
# only add default family if no other font was found and
# fallback_to_default is enabled
if not fpaths:
if fallback_to_default:
dfamily = self.defaultFamily[fontext]
cprop = prop.copy()
cprop.set_family(dfamily)
fpaths.append(
self.findfont(
cprop, fontext, directory,
fallback_to_default=True,
rebuild_if_missing=rebuild_if_missing,
)
)
else:
raise ValueError("Failed to find any font, and fallback "
"to the default font was disabled")
return fpaths
@lru_cache(1024)
def _findfont_cached(self, prop, fontext, directory, fallback_to_default,
rebuild_if_missing, rc_params):
prop = FontProperties._from_any(prop)
fname = prop.get_file()
if fname is not None:
return fname
if fontext == 'afm':
fontlist = self.afmlist
else:
fontlist = self.ttflist
best_score = 1e64
best_font = None
_log.debug('findfont: Matching %s.', prop)
for font in fontlist:
if (directory is not None and
Path(directory) not in Path(font.fname).parents):
continue
# Matching family should have top priority, so multiply it by 10.
score = (self.score_family(prop.get_family(), font.name) * 10
+ self.score_style(prop.get_style(), font.style)
+ self.score_variant(prop.get_variant(), font.variant)
+ self.score_weight(prop.get_weight(), font.weight)
+ self.score_stretch(prop.get_stretch(), font.stretch)
+ self.score_size(prop.get_size(), font.size))
_log.debug('findfont: score(%s) = %s', font, score)
if score < best_score:
best_score = score
best_font = font
if score == 0:
break
if best_font is None or best_score >= 10.0:
if fallback_to_default:
_log.warning(
'findfont: Font family %s not found. Falling back to %s.',
prop.get_family(), self.defaultFamily[fontext])
for family in map(str.lower, prop.get_family()):
if family in font_family_aliases:
_log.warning(
"findfont: Generic family %r not found because "
"none of the following families were found: %s",
family, ", ".join(self._expand_aliases(family)))
default_prop = prop.copy()
default_prop.set_family(self.defaultFamily[fontext])
return self.findfont(default_prop, fontext, directory,
fallback_to_default=False)
else:
# This return instead of raise is intentional, as we wish to
# cache that it was not found, which will not occur if it was
# actually raised.
return _ExceptionProxy(
ValueError,
f"Failed to find font {prop}, and fallback to the default font was disabled"
)
else:
_log.debug('findfont: Matching %s to %s (%r) with score of %f.',
prop, best_font.name, best_font.fname, best_score)
result = best_font.fname
if not os.path.isfile(result):
if rebuild_if_missing:
_log.info(
'findfont: Found a missing font file. Rebuilding cache.')
new_fm = _load_fontmanager(try_read_cache=False)
# Replace self by the new fontmanager, because users may have
# a reference to this specific instance.
# TODO: _load_fontmanager should really be (used by) a method
# modifying the instance in place.
vars(self).update(vars(new_fm))
return self.findfont(
prop, fontext, directory, rebuild_if_missing=False)
else:
# This return instead of raise is intentional, as we wish to
# cache that it was not found, which will not occur if it was
# actually raised.
return _ExceptionProxy(ValueError, "No valid font could be found")
return _cached_realpath(result)
@lru_cache()
def is_opentype_cff_font(filename):
"""
Return whether the given font is a Postscript Compact Font Format Font
embedded in an OpenType wrapper. Used by the PostScript and PDF backends
that can not subset these fonts.
"""
if os.path.splitext(filename)[1].lower() == '.otf':
with open(filename, 'rb') as fd:
return fd.read(4) == b"OTTO"
else:
return False
@lru_cache(64)
def _get_font(font_filepaths, hinting_factor, *, _kerning_factor, thread_id):
first_fontpath, *rest = font_filepaths
return ft2font.FT2Font(
first_fontpath, hinting_factor,
_fallback_list=[
ft2font.FT2Font(
fpath, hinting_factor,
_kerning_factor=_kerning_factor
)
for fpath in rest
],
_kerning_factor=_kerning_factor
)
# FT2Font objects cannot be used across fork()s because they reference the same
# FT_Library object. While invalidating *all* existing FT2Fonts after a fork
# would be too complicated to be worth it, the main way FT2Fonts get reused is
# via the cache of _get_font, which we can empty upon forking (not on Windows,
# which has no fork() or register_at_fork()).
if hasattr(os, "register_at_fork"):
os.register_at_fork(after_in_child=_get_font.cache_clear)
@lru_cache(64)
def _cached_realpath(path):
# Resolving the path avoids embedding the font twice in pdf/ps output if a
# single font is selected using two different relative paths.
return os.path.realpath(path)
@_api.rename_parameter('3.6', "filepath", "font_filepaths")
def get_font(font_filepaths, hinting_factor=None):
"""
Get an `.ft2font.FT2Font` object given a list of file paths.
Parameters
----------
font_filepaths : Iterable[str, Path, bytes], str, Path, bytes
Relative or absolute paths to the font files to be used.
If a single string, bytes, or `pathlib.Path`, then it will be treated
as a list with that entry only.
If more than one filepath is passed, then the returned FT2Font object
will fall back through the fonts, in the order given, to find a needed
glyph.
Returns
-------
`.ft2font.FT2Font`
"""
if isinstance(font_filepaths, (str, Path, bytes)):
paths = (_cached_realpath(font_filepaths),)
else:
paths = tuple(_cached_realpath(fname) for fname in font_filepaths)
if hinting_factor is None:
hinting_factor = mpl.rcParams['text.hinting_factor']
return _get_font(
# must be a tuple to be cached
paths,
hinting_factor,
_kerning_factor=mpl.rcParams['text.kerning_factor'],
# also key on the thread ID to prevent segfaults with multi-threading
thread_id=threading.get_ident()
)
def _load_fontmanager(*, try_read_cache=True):
fm_path = Path(
mpl.get_cachedir(), f"fontlist-v{FontManager.__version__}.json")
if try_read_cache:
try:
fm = json_load(fm_path)
except Exception:
pass
else:
if getattr(fm, "_version", object()) == FontManager.__version__:
_log.debug("Using fontManager instance from %s", fm_path)
return fm
fm = FontManager()
json_dump(fm, fm_path)
_log.info("generated new fontManager")
return fm
fontManager = _load_fontmanager()
findfont = fontManager.findfont
get_font_names = fontManager.get_font_names