commit b0e10dc6f9ca392e79779d95175bd93a80076f3a
Merge: d7499b9b98 0dcd06f812
Author: Jouni K. Seppänen <jks@iki.fi>
Date:   2025-06-24 18:26:38 +0300

    Merge branch 'main' into simple-dvifontinfo

diff --cc lib/matplotlib/backends/backend_pdf.py
index fc37a21bf4,6d6bea585f..9bb76d3688
--- a/lib/matplotlib/backends/backend_pdf.py
+++ b/lib/matplotlib/backends/backend_pdf.py
@@@ -716,19 -716,17 +716,17 @@@ class PdfFile
          root = {'Type': Name('Catalog'),
                  'Pages': self.pagesObject}
          self.writeObject(self.rootObject, root)
  
          self.infoDict = _create_pdf_info_dict('pdf', metadata or {})
  
          self._internal_font_seq = (Name(f'F{i}') for i in itertools.count(1))
          self._fontNames = {}     # maps filenames to internal font names
 -        self._dviFontInfo = {}   # maps dvi font names to embedding information
 +        self._dviFontInfo = {}   # maps pdf names to dvifonts
-         # differently encoded Type-1 fonts may share the same descriptor
-         self._type1Descriptors = {}
          self._character_tracker = _backend_pdf_ps.CharacterTracker()
  
          self.alphaStates = {}   # maps alpha values to graphics state objects
          self._alpha_state_seq = (Name(f'A{i}') for i in itertools.count(1))
          self._soft_mask_states = {}
          self._soft_mask_seq = (Name(f'SM{i}') for i in itertools.count(1))
          self._soft_mask_groups = []
          self._hatch_patterns = {}
@@@ -761,41 -759,19 +759,40 @@@
                       'XObject': self.XObjectObject,
                       'ExtGState': self._extGStateObject,
                       'Pattern': self.hatchObject,
                       'Shading': self.gouraudObject,
                       'ProcSet': procsets}
          self.writeObject(self.resourceObject, resources)
  
      fontNames = _api.deprecated("3.11")(property(lambda self: self._fontNames))
-     type1Descriptors = _api.deprecated("3.11")(
-         property(lambda self: self._type1Descriptors))
 -    dviFontInfo = _api.deprecated("3.11")(property(lambda self: self._dviFontInfo))
+     type1Descriptors = _api.deprecated("3.11")(property(lambda _: {}))
  
 +    @_api.deprecated("3.11")
 +    @property
 +    def dviFontInfo(self):
 +        d = {}
 +        tex_font_map = dviread.PsfontsMap(dviread.find_tex_file('pdftex.map'))
 +        for pdfname, dvifont in self._dviFontInfo.items():
 +            psfont = tex_font_map[dvifont.texname]
 +            if psfont.filename is None:
 +                raise ValueError(
 +                    "No usable font file found for {} (TeX: {}); "
 +                    "the font may lack a Type-1 version"
 +                    .format(psfont.psname, dvifont.texname))
 +            d[dvifont.texname] = types.SimpleNamespace(
 +                dvifont=dvifont,
 +                pdfname=pdfname,
 +                fontfile=psfont.filename,
 +                basefont=psfont.psname,
 +                encodingfile=psfont.encoding,
 +                effects=psfont.effects,
 +            )
 +        return d
 +
      def newPage(self, width, height):
          self.endStream()
  
          self.width, self.height = width, height
          contentObject = self.reserveObject('page contents')
          annotsObject = self.reserveObject('annotations')
          thePage = {'Type': Name('Page'),
                     'Parent': self.pagesObject,
@@@ -986,72 -993,74 +994,78 @@@
          fontdict = {'Type': Name('Font'),
                      'Subtype': Name('Type1'),
                      'BaseFont': Name(fontname),
                      'Encoding': Name('WinAnsiEncoding')}
          fontdictObject = self.reserveObject('font dictionary')
          self.writeObject(fontdictObject, fontdict)
          return fontdictObject
  
 -    def _embedTeXFont(self, fontinfo):
 -        _log.debug('Embedding TeX font %s - fontinfo=%s',
 -                   fontinfo.dvifont.texname, fontinfo.__dict__)
 +    def _embedTeXFont(self, dvifont):
 +        tex_font_map = dviread.PsfontsMap(dviread.find_tex_file('pdftex.map'))
 +        psfont = tex_font_map[dvifont.texname]
 +        if psfont.filename is None:
 +            raise ValueError(
 +                "No usable font file found for {} (TeX: {}); "
 +                "the font may lack a Type-1 version"
 +                .format(psfont.psname, dvifont.texname))
  
-         # Widths
-         widthsObject = self.reserveObject('font widths')
-         tfm = dvifont._tfm
-         # convert from TeX's 12.20 representation to 1/1000 text space units.
-         widths = [(1000 * metrics.tex_width) >> 20
-                   if (metrics := tfm.get_metrics(char)) else 0
-                   for char in range(max(tfm._glyph_metrics, default=-1) + 1)]
-         self.writeObject(widthsObject, widths)
- 
-         # Font dictionary
+         # The font dictionary is the top-level object describing a font
          fontdictObject = self.reserveObject('font dictionary')
          fontdict = {
              'Type':      Name('Font'),
              'Subtype':   Name('Type1'),
-             'FirstChar': 0,
-             'LastChar':  len(widths) - 1,
-             'Widths':    widthsObject,
-             }
+         }
  
-         # Encoding (if needed)
-         if psfont.encoding is not None:
-             fontdict['Encoding'] = {
-                 'Type': Name('Encoding'),
-                 'Differences': [
-                     0, *map(Name, dviread._parse_enc(psfont.encoding))],
-             }
- 
-         # We have a font file to embed - read it in and apply any effects
+         # Read the font file and apply any encoding changes and effects
 -        t1font = _type1font.Type1Font(fontinfo.fontfile)
 -        if fontinfo.encodingfile is not None:
 +        t1font = _type1font.Type1Font(psfont.filename)
++        if psfont.encoding is not None:
+             t1font = t1font.with_encoding(
 -                {i: c for i, c in enumerate(dviread._parse_enc(fontinfo.encodingfile))}
++                {i: c for i, c in enumerate(dviread._parse_enc(psfont.encoding))}
+             )
 -        if fontinfo.effects:
 -            t1font = t1font.transform(fontinfo.effects)
 +        if psfont.effects:
 +            t1font = t1font.transform(psfont.effects)
+ 
+         # Reduce the font to only the glyphs used in the document, get the encoding
+         # for that subset, and compute various properties based on the encoding.
 -        chars = frozenset(self._character_tracker.used[fontinfo.dvifont.fname])
++        chars = frozenset(self._character_tracker.used[dvifont.fname])
+         t1font = t1font.subset(chars, self._get_subset_prefix(chars))
          fontdict['BaseFont'] = Name(t1font.prop['FontName'])
+         # createType1Descriptor writes the font data as a side effect
+         fontdict['FontDescriptor'] = self.createType1Descriptor(t1font)
+         encoding = t1font.prop['Encoding']
+         fontdict['Encoding'] = self._generate_encoding(encoding)
+         fc = fontdict['FirstChar'] = min(encoding.keys(), default=0)
+         lc = fontdict['LastChar'] = max(encoding.keys(), default=255)
  
-         # Font descriptors may be shared between differently encoded
-         # Type-1 fonts, so only create a new descriptor if there is no
-         # existing descriptor for this font.
-         effects = (psfont.effects.get('slant', 0.0),
-                    psfont.effects.get('extend', 1.0))
-         fontdesc = self._type1Descriptors.get((psfont.filename, effects))
-         if fontdesc is None:
-             fontdesc = self._type1Descriptors[psfont.filename, effects] = \
-                 self.createType1Descriptor(t1font)
-         fontdict['FontDescriptor'] = fontdesc
- 
+         # Convert glyph widths from TeX 12.20 fixed point to 1/1000 text space units
 -        tfm = fontinfo.dvifont._tfm
++        tfm = dvifont._tfm
+         widths = [(1000 * metrics.tex_width) >> 20
+                   if (metrics := tfm.get_metrics(char)) else 0
+                   for char in range(fc, lc + 1)]
+         fontdict['Widths'] = widthsObject = self.reserveObject('glyph widths')
+         self.writeObject(widthsObject, widths)
 -
          self.writeObject(fontdictObject, fontdict)
          return fontdictObject
  
+ 
+     def _generate_encoding(self, encoding):
+         prev = -2
+         result = []
+         for code, name in sorted(encoding.items()):
+             if code != prev + 1:
+                 result.append(code)
+             prev = code
+             result.append(Name(name))
+         return {
+             'Type': Name('Encoding'),
+             'Differences': result
+         }
+ 
+ 
      @_api.delete_parameter("3.11", "fontfile")
      def createType1Descriptor(self, t1font, fontfile=None):
          # Create and write the font descriptor and the font file
          # of a Type-1 font
          fontdescObject = self.reserveObject('font descriptor')
          fontfileObject = self.reserveObject('font file')
  
          italic_angle = t1font.prop['ItalicAngle']