font/pfmfile.py

   1 # -*- encoding: utf-8 -*-
   2 #
   3 #
   4 # Copyright (C) 2007-2011 André Wobst <wobsta@users.sourceforge.net>
   5 #
   6 # This file is part of PyX (http://pyx.sourceforge.net/).
   7 #
   8 # PyX is free software; you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation; either version 2 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # PyX is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with PyX; if not, write to the Free Software
  20 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  21
  22 import struct, re
  23 from . import metric
  24
  25
  26 ansiglyphs = {"space": 32,
  27               "exclam": 33,
  28               "quotedbl": 34,
  29               "numbersign": 35,
  30               "dollar": 36,
  31               "percent": 37,
  32               "ampersand": 38,
  33               "quotesingle": 39,
  34               "parenleft": 40,
  35               "parenright": 41,
  36               "asterisk": 42,
  37               "plus": 43,
  38               "comma": 44,
  39               "hyphen": 45,
  40               "period": 46,
  41               "slash": 47,
  42               "zero": 48,
  43               "one": 49,
  44               "two": 50,
  45               "three": 51,
  46               "four": 52,
  47               "five": 53,
  48               "six": 54,
  49               "seven": 55,
  50               "eight": 56,
  51               "nine": 57,
  52               "colon": 58,
  53               "semicolon": 59,
  54               "less": 60,
  55               "equal": 61,
  56               "greater": 62,
  57               "question": 63,
  58               "at": 64,
  59               "A": 65,
  60               "B": 66,
  61               "C": 67,
  62               "D": 68,
  63               "E": 69,
  64               "F": 70,
  65               "G": 71,
  66               "H": 72,
  67               "I": 73,
  68               "J": 74,
  69               "K": 75,
  70               "L": 76,
  71               "M": 77,
  72               "N": 78,
  73               "O": 79,
  74               "P": 80,
  75               "Q": 81,
  76               "R": 82,
  77               "S": 83,
  78               "T": 84,
  79               "U": 85,
  80               "V": 86,
  81               "W": 87,
  82               "X": 88,
  83               "Y": 89,
  84               "Z": 90,
  85               "bracketleft": 91,
  86               "backslash": 92,
  87               "bracketright": 93,
  88               "asciicircum": 94,
  89               "underscore": 95,
  90               "grave": 96,
  91               "a": 97,
  92               "b": 98,
  93               "c": 99,
  94               "d": 100,
  95               "e":101,
  96               "f":102,
  97               "g":103,
  98               "h":104,
  99               "i":105,
 100               "j":106,
 101               "k":107,
 102               "l":108,
 103               "m":109,
 104               "n":110,
 105               "o":111,
 106               "p":112,
 107               "q":113,
 108               "r":114,
 109               "s":115,
 110               "t":116,
 111               "u":117,
 112               "v":118,
 113               "w":119,
 114               "x":120,
 115               "y":121,
 116               "z":122,
 117               "braceleft":123,
 118               "bar":124,
 119               "braceright":125,
 120               "asciitilde":126,
 121               "bullet":127,
 122               "Euro":128,
 123               "bullet":129,
 124               "quotesinglbase":130,
 125               "florin":131,
 126               "quotedblbase":132,
 127               "ellipsis":133,
 128               "dagger":134,
 129               "daggerdbl":135,
 130               "circumflex":136,
 131               "perthousand":137,
 132               "Scaron":138,
 133               "guilsinglleft":139,
 134               "OE":140,
 135               "bullet":141,
 136               "Zcaron":142,
 137               "bullet":143,
 138               "bullet":144,
 139               "quoteleft":145,
 140               "quoteright":146,
 141               "quotedblleft":147,
 142               "quotedblright":148,
 143               "bullet":149,
 144               "endash":150,
 145               "emdash":151,
 146               "tilde":152,
 147               "trademark":153,
 148               "scaron":154,
 149               "guilsinglright":155,
 150               "oe":156,
 151               "bullet":157,
 152               "zcaron":158,
 153               "Ydieresis":159,
 154               "space":160,
 155               "exclamdown":161,
 156               "cent":162,
 157               "sterling":163,
 158               "currency":164,
 159               "yen":165,
 160               "brokenbar":166,
 161               "section":167,
 162               "dieresis":168,
 163               "copyright":169,
 164               "ordfeminine":170,
 165               "guillemotleft":171,
 166               "logicalnot":172,
 167               "hyphen":173,
 168               "registered":174,
 169               "macron":175,
 170               "degree":176,
 171               "plusminus":177,
 172               "twosuperior":178,
 173               "threesuperior":179,
 174               "acute":180,
 175               "mu":181,
 176               "paragraph":182,
 177               "periodcentered":183,
 178               "cedilla":184,
 179               "onesuperior":185,
 180               "ordmasculine":186,
 181               "guillemotright":187,
 182               "onequarter":188,
 183               "onehalf":189,
 184               "threequarters":190,
 185               "questiondown":191,
 186               "Agrave":192,
 187               "Aacute":193,
 188               "Acircumflex":194,
 189               "Atilde":195,
 190               "Adieresis":196,
 191               "Aring":197,
 192               "AE":198,
 193               "Ccedilla":199,
 194               "Egrave":200,
 195               "Eacute":201,
 196               "Ecircumflex":202,
 197               "Edieresis":203,
 198               "Igrave":204,
 199               "Iacute":205,
 200               "Icircumflex":206,
 201               "Idieresis":207,
 202               "Eth":208,
 203               "Ntilde":209,
 204               "Ograve":210,
 205               "Oacute":211,
 206               "Ocircumflex":212,
 207               "Otilde":213,
 208               "Odieresis":214,
 209               "multiply":215,
 210               "Oslash":216,
 211               "Ugrave":217,
 212               "Uacute":218,
 213               "Ucircumflex":219,
 214               "Udieresis":220,
 215               "Yacute":221,
 216               "Thorn":222,
 217               "germandbls":223,
 218               "agrave":224,
 219               "aacute":225,
 220               "acircumflex":226,
 221               "atilde":227,
 222               "adieresis":228,
 223               "aring":229,
 224               "ae":230,
 225               "ccedilla":231,
 226               "egrave":232,
 227               "eacute":233,
 228               "ecircumflex":234,
 229               "edieresis":235,
 230               "igrave":236,
 231               "iacute":237,
 232               "icircumflex":238,
 233               "idieresis":239,
 234               "eth":240,
 235               "ntilde":241,
 236               "ograve":242,
 237               "oacute":243,
 238               "ocircumflex":244,
 239               "otilde":245,
 240               "odieresis":246,
 241               "divide":247,
 242               "oslash":248,
 243               "ugrave":249,
 244               "uacute":250,
 245               "ucircumflex":251,
 246               "udieresis":252,
 247               "yacute":253,
 248               "thorn":254,
 249               "ydieresis":255}
 250
 251
 252 fontbboxpattern = re.compile("/FontBBox\s*\{\s*(?P<fontbbox>(-?[0-9.]+)\s+(-?[0-9.]+)\s+(-?[0-9.]+)\s+(-?[0-9.]+))\s*\}\s*(readonly\s+)?def")
 253
 254
 255 def _readNullString(file):
 256     s = []
 257     c = file.read(1)
 258     while c and c != "\0":
 259         s.append(c)
 260         c = file.read(1)
 261     return "".join(s)
 262
 263
 264 class PFMfile(metric.metric):
 265
 266     def __init__(self, file, t1file):
 267         # pfm is rather incomplete, the t1file instance can be used to fill the gap
 268         (self.dfVersion, self.dfSize, self.dfCopyright, self.dfType,
 269          self.dfPoint, self.dfVertRes, self.dfHorizRes, self.dfAscent,
 270          self.dfInternalLeading, self.dfExternalLeading, self.dfItalic,
 271          self.dfUnderline, self.dfStrikeOut, self.dfWeight,
 272          self.dfCharSet, self.dfPixWidth, self.dfPixHeight,
 273          self.dfPitchAndFamily, self.dfAvgWidth, self.dfMaxWidth,
 274          self.dfFirstChar, self.dfLastChar, self.dfDefaultChar,
 275          self.dfBreakChar, self.dfWidthBytes, self.dfDevice, self.dfFace,
 276          self.dfBitsPointer, self.dfBitsOffset) = struct.unpack("<HL60s7H3BHB2HB2H4BH4L", file.read(117))
 277         self.dfCopyright = self.dfCopyright.split("\000", 1)[0]
 278         (self.dfSizeFields, self.dfExtMetricsOffset, self.dfExtentTable,
 279          self.dfOriginTable, self.dfPairKernTable, self.dfTrackKernTable,
 280          self.dfDriverInfo, self.dfReserved) = struct.unpack("<H7L", file.read(30))
 281         if self.dfDevice == 0:
 282             raise ValueError("DeviceName is required for Type1 pfm files.")
 283         file.seek(self.dfDevice)
 284         self.deviceName = _readNullString(file)
 285         if self.deviceName.lower() != "postscript":
 286             raise ValueError("Can process pfm files for PostScript fonts only.")
 287         if self.dfVersion != 0x100:
 288             raise ValueError("Invalid pfm file version.")
 289         if self.dfType != 0x81:
 290             raise ValueError("Not a Type1 pfm file.")
 291         if self.dfFace == 0:
 292             raise ValueError("FaceName is required for Type1 pfm files.")
 293         if self.dfExtMetricsOffset == 0:
 294             raise ValueError("ExtTextMetrics is required for Type1 pfm files.")
 295         if self.dfExtentTable == 0:
 296             raise ValueError("ExtentTable is required for Type1 pfm files.")
 297         if self.dfOriginTable != 0:
 298             raise ValueError("OriginTable is forbidden for Type1 pfm files.")
 299         if self.dfDriverInfo == 0:
 300             raise ValueError("DriverInfo is required for Type1 pfm files.")
 301         # assert self.dfReserved == 0 (must be zero according to the spec, but we don't care)
 302         file.seek(self.dfExtMetricsOffset)
 303         (etmSize, self.etmPointSize, self.etmOrientation,
 304          self.etmMasterHeight, self.etmMinScale, self.etmMaxScale,
 305          self.etmMasterUnits, self.etmCapHeight, self.etmXHeight,
 306          self.etmLowerCaseAscent, self.etmLowerCaseDescent, self.etmSlant,
 307          self.etmSuperScript, self.etmSubScript, self.etmSuperScriptSize,
 308          self.etmSubScriptSize, self.etmUnderlineOffset,
 309          self.etmUnderlineWidth, self.etmDoubleUpperUnderlineOffset,
 310          self.etmDoubleLowerUnderlineOffset, self.etmDoubleUpperUnderlineWidth,
 311          self.etmDoubleLowerUnderlineWidth, self.etmStrikeOutOffset,
 312          self.etmStrikeOutWidth, self.etmKernPairs, self.etmKernTracks) = struct.unpack("<24h2H", file.read(52))
 313         file.seek(self.dfFace)
 314         self.faceName = _readNullString(file)
 315         file.seek(self.dfDriverInfo)
 316         self.driverInfo = _readNullString(file)
 317         file.seek(self.dfExtentTable)
 318         count = self.dfLastChar - self.dfFirstChar + 1
 319         self.widths = struct.unpack("<%dH" % count, file.read(2*count))
 320         self.kernpairs = []
 321         self.kernpairsdict = {}
 322         if self.dfPairKernTable:
 323             file.seek(self.dfPairKernTable)
 324             pairs, = struct.unpack("<H", file.read(2))
 325             if pairs != self.etmKernPairs:
 326                 raise ValueError("number of kerning pairs mismatch in pfm file.")
 327             for i in range(self.etmKernPairs):
 328                 kpFirst, kpSecond, kpKernAmount = struct.unpack("<BBh", file.read(4))
 329                 self.kernpairs.append((kpFirst, kpSecond, kpKernAmount))
 330                 self.kernpairsdict[(kpFirst, kpSecond)] = kpKernAmount
 331         self.trackkerns = []
 332         if self.dfTrackKernTable:
 333             file.seek(self.dfTrackKernTable)
 334             items, = struct.unpack("<H", file.read(2))
 335             if items != self.etmKernTracks:
 336                 raise ValueError("number of kerning tracks mismatch in pfm file.")
 337             for i in range(self.etmKernTracks):
 338                 # each item consists of the tuple ktDegree, ktMinSize, ktMinAmount, ktMaxSize, ktMaxAmount
 339                 self.trackkerns.append(struct.unpack("<hhhhh", file.read(10)))
 340         if self.dfCharSet:
 341             if not t1file.encoding:
 342                 t1file._encoding()
 343             self.glyphs = dict([(glyph, i) for i, glyph in enumerate(t1file.encoding) if glyph != None])
 344         else:
 345             self.glyphs = ansiglyphs
 346         self.t1file = t1file
 347
 348     def width_ds(self, glyphname):
 349         return self.widths[self.glyphs[glyphname]-self.dfFirstChar]
 350
 351     def width_pt(self, glyphnames, size_pt):
 352         return sum([self.widths[self.glyphs[glyphname]-self.dfFirstChar] for glyphname in glyphnames])*size_pt/1000.0
 353
 354     def height_pt(self, glyphnames, size_pt):
 355         return self.dfAscent*size_pt/1000.0
 356
 357     def depth_pt(self, glyphnames, size_pt):
 358         return -self.etmLowerCaseDescent*size_pt/1000.0
 359
 360     def resolvekernings(self, glyphnames, size_pt=None):
 361         result = [None]*(2*len(glyphnames)-1)
 362         for i, glyphname in enumerate(glyphnames):
 363             result[2*i] = glyphname
 364         return result
 365
 366     def resolvekernings(self, glyphnames, size_pt=None):
 367         result = [None]*(2*len(glyphnames)-1)
 368         for i, glyphname in enumerate(glyphnames):
 369             result[2*i] = glyphname
 370             if i:
 371                 amount = self.kernpairsdict.get((self.glyphs[glyphnames[i-1]], self.glyphs[glyphname]))
 372                 if amount:
 373                     if size_pt is not None:
 374                         result[2*i-1] = amount*size_pt/1000.0
 375                     else:
 376                         result[2*i-1] = amount
 377         return result
 378
 379     def writePDFfontinfo(self, file, seriffont=False, symbolfont=True):
 380         flags = 0
 381         if self.dfMaxWidth == self.dfAvgWidth:
 382             flags += 1<<0
 383         if seriffont:
 384             flags += 1<<1
 385         if symbolfont:
 386             flags += 1<<2
 387         else:
 388             flags += 1<<5
 389         if self.dfItalic:
 390             flags += 1<<6
 391         file.write("/Flags %d\n" % flags)
 392         file.write("/ItalicAngles %d\n" % (self.etmSlant/10))
 393         file.write("/Ascent %d\n" % self.dfAscent)
 394         file.write("/Descent %d\n" % -self.etmLowerCaseDescent)
 395         file.write("/FontBBox [%s]\n" % fontbboxpattern.search(self.t1file.data1).groups('fontbbox')[0])
 396         file.write("/CapHeight %d\n" % self.etmCapHeight)
 397         if self.dfWeight >= 600:
 398             stemv = 120
 399         else:
 400             stemv = 70
 401         file.write("/StemV %d\n" % stemv)
 402