Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/matplotlib/backends/_backend_pdf_ps.py

121 lines
3.7 KiB
Python

"""
Common functionality between the PDF and PS backends.
"""
import functools
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)
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 = {}
@mpl.cbook.deprecated("3.3")
@property
def used_characters(self):
d = {}
for fname, chars in self.used.items():
realpath, stat_key = mpl.cbook.get_realpath_and_stat(fname)
d[stat_key] = (realpath, chars)
return d
def track(self, font, s):
"""Record that string *s* is being typeset using font *font*."""
if isinstance(font, str):
# Unused, can be removed after removal of track_characters.
fname = font
else:
fname = font.fname
self.used.setdefault(fname, set()).update(map(ord, s))
def merge(self, other):
"""Update self with a font path to character codepoints."""
for fname, charset in other.items():
self.used.setdefault(fname, set()).update(charset)
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":
texmanager = self.get_texmanager()
fontsize = prop.get_size_in_points()
w, h, d = texmanager.get_text_width_height_descent(
s, fontsize, renderer=self)
return w, h, d
elif ismath:
parse = self.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.LOAD_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):
fname = font_manager.findfont(prop)
font = font_manager.get_font(fname)
font.clear()
font.set_size(prop.get_size_in_points(), 72)
return font