You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
370 lines
15 KiB
Python
370 lines
15 KiB
Python
r"""
|
|
Support for embedded TeX expressions in Matplotlib.
|
|
|
|
Requirements:
|
|
|
|
* LaTeX.
|
|
* \*Agg backends: dvipng>=1.6.
|
|
* PS backend: PSfrag, dvips, and Ghostscript>=9.0.
|
|
* PDF and SVG backends: if LuaTeX is present, it will be used to speed up some
|
|
post-processing steps, but note that it is not used to parse the TeX string
|
|
itself (only LaTeX is supported).
|
|
|
|
To enable TeX rendering of all text in your Matplotlib figure, set
|
|
:rc:`text.usetex` to True.
|
|
|
|
TeX and dvipng/dvips processing results are cached
|
|
in ~/.matplotlib/tex.cache for reuse between sessions.
|
|
|
|
`TexManager.get_rgba` can also be used to directly obtain raster output as RGBA
|
|
NumPy arrays.
|
|
"""
|
|
|
|
import functools
|
|
import hashlib
|
|
import logging
|
|
import os
|
|
from pathlib import Path
|
|
import subprocess
|
|
from tempfile import TemporaryDirectory
|
|
|
|
import numpy as np
|
|
|
|
import matplotlib as mpl
|
|
from matplotlib import cbook, dviread
|
|
|
|
_log = logging.getLogger(__name__)
|
|
|
|
|
|
def _usepackage_if_not_loaded(package, *, option=None):
|
|
"""
|
|
Output LaTeX code that loads a package (possibly with an option) if it
|
|
hasn't been loaded yet.
|
|
|
|
LaTeX cannot load twice a package with different options, so this helper
|
|
can be used to protect against users loading arbitrary packages/options in
|
|
their custom preamble.
|
|
"""
|
|
option = f"[{option}]" if option is not None else ""
|
|
return (
|
|
r"\makeatletter"
|
|
r"\@ifpackageloaded{%(package)s}{}{\usepackage%(option)s{%(package)s}}"
|
|
r"\makeatother"
|
|
) % {"package": package, "option": option}
|
|
|
|
|
|
class TexManager:
|
|
"""
|
|
Convert strings to dvi files using TeX, caching the results to a directory.
|
|
|
|
The cache directory is called ``tex.cache`` and is located in the directory
|
|
returned by `.get_cachedir`.
|
|
|
|
Repeated calls to this constructor always return the same instance.
|
|
"""
|
|
|
|
_texcache = os.path.join(mpl.get_cachedir(), 'tex.cache')
|
|
_grey_arrayd = {}
|
|
|
|
_font_families = ('serif', 'sans-serif', 'cursive', 'monospace')
|
|
_font_preambles = {
|
|
'new century schoolbook': r'\renewcommand{\rmdefault}{pnc}',
|
|
'bookman': r'\renewcommand{\rmdefault}{pbk}',
|
|
'times': r'\usepackage{mathptmx}',
|
|
'palatino': r'\usepackage{mathpazo}',
|
|
'zapf chancery': r'\usepackage{chancery}',
|
|
'cursive': r'\usepackage{chancery}',
|
|
'charter': r'\usepackage{charter}',
|
|
'serif': '',
|
|
'sans-serif': '',
|
|
'helvetica': r'\usepackage{helvet}',
|
|
'avant garde': r'\usepackage{avant}',
|
|
'courier': r'\usepackage{courier}',
|
|
# Loading the type1ec package ensures that cm-super is installed, which
|
|
# is necessary for Unicode computer modern. (It also allows the use of
|
|
# computer modern at arbitrary sizes, but that's just a side effect.)
|
|
'monospace': r'\usepackage{type1ec}',
|
|
'computer modern roman': r'\usepackage{type1ec}',
|
|
'computer modern sans serif': r'\usepackage{type1ec}',
|
|
'computer modern typewriter': r'\usepackage{type1ec}',
|
|
}
|
|
_font_types = {
|
|
'new century schoolbook': 'serif',
|
|
'bookman': 'serif',
|
|
'times': 'serif',
|
|
'palatino': 'serif',
|
|
'zapf chancery': 'cursive',
|
|
'charter': 'serif',
|
|
'helvetica': 'sans-serif',
|
|
'avant garde': 'sans-serif',
|
|
'courier': 'monospace',
|
|
'computer modern roman': 'serif',
|
|
'computer modern sans serif': 'sans-serif',
|
|
'computer modern typewriter': 'monospace',
|
|
}
|
|
|
|
@functools.lru_cache # Always return the same instance.
|
|
def __new__(cls):
|
|
Path(cls._texcache).mkdir(parents=True, exist_ok=True)
|
|
return object.__new__(cls)
|
|
|
|
@classmethod
|
|
def _get_font_family_and_reduced(cls):
|
|
"""Return the font family name and whether the font is reduced."""
|
|
ff = mpl.rcParams['font.family']
|
|
ff_val = ff[0].lower() if len(ff) == 1 else None
|
|
if len(ff) == 1 and ff_val in cls._font_families:
|
|
return ff_val, False
|
|
elif len(ff) == 1 and ff_val in cls._font_preambles:
|
|
return cls._font_types[ff_val], True
|
|
else:
|
|
_log.info('font.family must be one of (%s) when text.usetex is '
|
|
'True. serif will be used by default.',
|
|
', '.join(cls._font_families))
|
|
return 'serif', False
|
|
|
|
@classmethod
|
|
def _get_font_preamble_and_command(cls):
|
|
requested_family, is_reduced_font = cls._get_font_family_and_reduced()
|
|
|
|
preambles = {}
|
|
for font_family in cls._font_families:
|
|
if is_reduced_font and font_family == requested_family:
|
|
preambles[font_family] = cls._font_preambles[
|
|
mpl.rcParams['font.family'][0].lower()]
|
|
else:
|
|
rcfonts = mpl.rcParams[f"font.{font_family}"]
|
|
for i, font in enumerate(map(str.lower, rcfonts)):
|
|
if font in cls._font_preambles:
|
|
preambles[font_family] = cls._font_preambles[font]
|
|
_log.debug(
|
|
'family: %s, package: %s, font: %s, skipped: %s',
|
|
font_family, cls._font_preambles[font], rcfonts[i],
|
|
', '.join(rcfonts[:i]),
|
|
)
|
|
break
|
|
else:
|
|
_log.info('No LaTeX-compatible font found for the %s font'
|
|
'family in rcParams. Using default.',
|
|
font_family)
|
|
preambles[font_family] = cls._font_preambles[font_family]
|
|
|
|
# The following packages and commands need to be included in the latex
|
|
# file's preamble:
|
|
cmd = {preambles[family]
|
|
for family in ['serif', 'sans-serif', 'monospace']}
|
|
if requested_family == 'cursive':
|
|
cmd.add(preambles['cursive'])
|
|
cmd.add(r'\usepackage{type1cm}')
|
|
preamble = '\n'.join(sorted(cmd))
|
|
fontcmd = (r'\sffamily' if requested_family == 'sans-serif' else
|
|
r'\ttfamily' if requested_family == 'monospace' else
|
|
r'\rmfamily')
|
|
return preamble, fontcmd
|
|
|
|
@classmethod
|
|
def get_basefile(cls, tex, fontsize, dpi=None):
|
|
"""
|
|
Return a filename based on a hash of the string, fontsize, and dpi.
|
|
"""
|
|
src = cls._get_tex_source(tex, fontsize) + str(dpi)
|
|
filehash = hashlib.sha256(
|
|
src.encode('utf-8'),
|
|
usedforsecurity=False
|
|
).hexdigest()
|
|
filepath = Path(cls._texcache)
|
|
|
|
num_letters, num_levels = 2, 2
|
|
for i in range(0, num_letters*num_levels, num_letters):
|
|
filepath = filepath / Path(filehash[i:i+2])
|
|
|
|
filepath.mkdir(parents=True, exist_ok=True)
|
|
return os.path.join(filepath, filehash)
|
|
|
|
@classmethod
|
|
def get_font_preamble(cls):
|
|
"""
|
|
Return a string containing font configuration for the tex preamble.
|
|
"""
|
|
font_preamble, command = cls._get_font_preamble_and_command()
|
|
return font_preamble
|
|
|
|
@classmethod
|
|
def get_custom_preamble(cls):
|
|
"""Return a string containing user additions to the tex preamble."""
|
|
return mpl.rcParams['text.latex.preamble']
|
|
|
|
@classmethod
|
|
def _get_tex_source(cls, tex, fontsize):
|
|
"""Return the complete TeX source for processing a TeX string."""
|
|
font_preamble, fontcmd = cls._get_font_preamble_and_command()
|
|
baselineskip = 1.25 * fontsize
|
|
return "\n".join([
|
|
r"\documentclass{article}",
|
|
r"% Pass-through \mathdefault, which is used in non-usetex mode",
|
|
r"% to use the default text font but was historically suppressed",
|
|
r"% in usetex mode.",
|
|
r"\newcommand{\mathdefault}[1]{#1}",
|
|
font_preamble,
|
|
r"\usepackage[utf8]{inputenc}",
|
|
r"\DeclareUnicodeCharacter{2212}{\ensuremath{-}}",
|
|
r"% geometry is loaded before the custom preamble as ",
|
|
r"% convert_psfrags relies on a custom preamble to change the ",
|
|
r"% geometry.",
|
|
r"\usepackage[papersize=72in, margin=1in]{geometry}",
|
|
cls.get_custom_preamble(),
|
|
r"% Use `underscore` package to take care of underscores in text.",
|
|
r"% The [strings] option allows to use underscores in file names.",
|
|
_usepackage_if_not_loaded("underscore", option="strings"),
|
|
r"% Custom packages (e.g. newtxtext) may already have loaded ",
|
|
r"% textcomp with different options.",
|
|
_usepackage_if_not_loaded("textcomp"),
|
|
r"\pagestyle{empty}",
|
|
r"\begin{document}",
|
|
r"% The empty hbox ensures that a page is printed even for empty",
|
|
r"% inputs, except when using psfrag which gets confused by it.",
|
|
r"% matplotlibbaselinemarker is used by dviread to detect the",
|
|
r"% last line's baseline.",
|
|
rf"\fontsize{{{fontsize}}}{{{baselineskip}}}%",
|
|
r"\ifdefined\psfrag\else\hbox{}\fi%",
|
|
rf"{{{fontcmd} {tex}}}%",
|
|
r"\end{document}",
|
|
])
|
|
|
|
@classmethod
|
|
def make_tex(cls, tex, fontsize):
|
|
"""
|
|
Generate a tex file to render the tex string at a specific font size.
|
|
|
|
Return the file name.
|
|
"""
|
|
texfile = cls.get_basefile(tex, fontsize) + ".tex"
|
|
Path(texfile).write_text(cls._get_tex_source(tex, fontsize),
|
|
encoding='utf-8')
|
|
return texfile
|
|
|
|
@classmethod
|
|
def _run_checked_subprocess(cls, command, tex, *, cwd=None):
|
|
_log.debug(cbook._pformat_subprocess(command))
|
|
try:
|
|
report = subprocess.check_output(
|
|
command, cwd=cwd if cwd is not None else cls._texcache,
|
|
stderr=subprocess.STDOUT)
|
|
except FileNotFoundError as exc:
|
|
raise RuntimeError(
|
|
f'Failed to process string with tex because {command[0]} '
|
|
'could not be found') from exc
|
|
except subprocess.CalledProcessError as exc:
|
|
raise RuntimeError(
|
|
'{prog} was not able to process the following string:\n'
|
|
'{tex!r}\n\n'
|
|
'Here is the full command invocation and its output:\n\n'
|
|
'{format_command}\n\n'
|
|
'{exc}\n\n'.format(
|
|
prog=command[0],
|
|
format_command=cbook._pformat_subprocess(command),
|
|
tex=tex.encode('unicode_escape'),
|
|
exc=exc.output.decode('utf-8', 'backslashreplace'))
|
|
) from None
|
|
_log.debug(report)
|
|
return report
|
|
|
|
@classmethod
|
|
def make_dvi(cls, tex, fontsize):
|
|
"""
|
|
Generate a dvi file containing latex's layout of tex string.
|
|
|
|
Return the file name.
|
|
"""
|
|
dvifile = Path(cls.get_basefile(tex, fontsize)).with_suffix(".dvi")
|
|
if not dvifile.exists():
|
|
# Generate the tex and dvi in a temporary directory to avoid race
|
|
# conditions e.g. if multiple processes try to process the same tex
|
|
# string at the same time. Having tmpdir be a subdirectory of the
|
|
# final output dir ensures that they are on the same filesystem,
|
|
# and thus replace() works atomically. It also allows referring to
|
|
# the texfile with a relative path (for pathological MPLCONFIGDIRs,
|
|
# the absolute path may contain characters (e.g. ~) that TeX does
|
|
# not support; n.b. relative paths cannot traverse parents, or it
|
|
# will be blocked when `openin_any = p` in texmf.cnf).
|
|
with TemporaryDirectory(dir=dvifile.parent) as tmpdir:
|
|
Path(tmpdir, "file.tex").write_text(
|
|
cls._get_tex_source(tex, fontsize), encoding='utf-8')
|
|
cls._run_checked_subprocess(
|
|
["latex", "-interaction=nonstopmode", "--halt-on-error",
|
|
"file.tex"], tex, cwd=tmpdir)
|
|
Path(tmpdir, "file.dvi").replace(dvifile)
|
|
# Also move the tex source to the main cache directory, but
|
|
# only for backcompat.
|
|
Path(tmpdir, "file.tex").replace(dvifile.with_suffix(".tex"))
|
|
return str(dvifile)
|
|
|
|
@classmethod
|
|
def make_png(cls, tex, fontsize, dpi):
|
|
"""
|
|
Generate a png file containing latex's rendering of tex string.
|
|
|
|
Return the file name.
|
|
"""
|
|
pngfile = Path(cls.get_basefile(tex, fontsize, dpi)).with_suffix(".png")
|
|
# see get_rgba for a discussion of the background
|
|
if not pngfile.exists():
|
|
dvifile = cls.make_dvi(tex, fontsize)
|
|
with TemporaryDirectory(dir=pngfile.parent) as tmpdir:
|
|
cmd = ["dvipng", "-bg", "Transparent", "-D", str(dpi),
|
|
"-T", "tight", "-o", "file.png", dvifile]
|
|
# When testing, disable FreeType rendering for reproducibility;
|
|
# but dvipng 1.16 has a bug (fixed in f3ff241) that breaks
|
|
# --freetype0 mode, so for it we keep FreeType enabled; the
|
|
# image will be slightly off.
|
|
if (getattr(mpl, "_called_from_pytest", False) and
|
|
mpl._get_executable_info("dvipng").raw_version != "1.16"):
|
|
cmd.insert(1, "--freetype0")
|
|
cls._run_checked_subprocess(cmd, tex, cwd=tmpdir)
|
|
Path(tmpdir, "file.png").replace(pngfile)
|
|
return str(pngfile)
|
|
|
|
@classmethod
|
|
def get_grey(cls, tex, fontsize=None, dpi=None):
|
|
"""Return the alpha channel."""
|
|
if not fontsize:
|
|
fontsize = mpl.rcParams['font.size']
|
|
if not dpi:
|
|
dpi = mpl.rcParams['savefig.dpi']
|
|
key = cls._get_tex_source(tex, fontsize), dpi
|
|
alpha = cls._grey_arrayd.get(key)
|
|
if alpha is None:
|
|
pngfile = cls.make_png(tex, fontsize, dpi)
|
|
rgba = mpl.image.imread(os.path.join(cls._texcache, pngfile))
|
|
cls._grey_arrayd[key] = alpha = rgba[:, :, -1]
|
|
return alpha
|
|
|
|
@classmethod
|
|
def get_rgba(cls, tex, fontsize=None, dpi=None, rgb=(0, 0, 0)):
|
|
r"""
|
|
Return latex's rendering of the tex string as an RGBA array.
|
|
|
|
Examples
|
|
--------
|
|
>>> texmanager = TexManager()
|
|
>>> s = r"\TeX\ is $\displaystyle\sum_n\frac{-e^{i\pi}}{2^n}$!"
|
|
>>> Z = texmanager.get_rgba(s, fontsize=12, dpi=80, rgb=(1, 0, 0))
|
|
"""
|
|
alpha = cls.get_grey(tex, fontsize, dpi)
|
|
rgba = np.empty((*alpha.shape, 4))
|
|
rgba[..., :3] = mpl.colors.to_rgb(rgb)
|
|
rgba[..., -1] = alpha
|
|
return rgba
|
|
|
|
@classmethod
|
|
def get_text_width_height_descent(cls, tex, fontsize, renderer=None):
|
|
"""Return width, height and descent of the text."""
|
|
if tex.strip() == '':
|
|
return 0, 0, 0
|
|
dvifile = cls.make_dvi(tex, fontsize)
|
|
dpi_fraction = renderer.points_to_pixels(1.) if renderer else 1
|
|
with dviread.Dvi(dvifile, 72 * dpi_fraction) as dvi:
|
|
page, = dvi
|
|
# A total height (including the descent) needs to be returned.
|
|
return page.width, page.height + page.descent, page.descent
|