Add files using upload-large-folder tool

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"""
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

	"""
	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