pyx/font/font.py

   1 # -*- coding: ISO-8859-1 -*-
   2 #
   3 #
   4 # Copyright (C) 2005-2007 Jörg Lehmann <joergl@users.sourceforge.net>
   5 # Copyright (C) 2005-2007 André Wobst <wobsta@users.sourceforge.net>
   6 #
   7 # This file is part of PyX (http://pyx.sourceforge.net/).
   8 #
   9 # PyX is free software; you can redistribute it and/or modify
  10 # it under the terms of the GNU General Public License as published by
  11 # the Free Software Foundation; either version 2 of the License, or
  12 # (at your option) any later version.
  13 #
  14 # PyX is distributed in the hope that it will be useful,
  15 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 # GNU General Public License for more details.
  18 #
  19 # You should have received a copy of the GNU General Public License
  20 # along with PyX; if not, write to the Free Software
  21 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  22
  23 from pyx import bbox, canvasitem, deco, path, pswriter, pdfwriter, trafo, unit
  24 import t1file
  25
  26 try:
  27     set()
  28 except NameError:
  29     # Python 2.3
  30     from sets import Set as set
  31
  32
  33 ##############################################################################
  34 # PS resources
  35 ##############################################################################
  36
  37 class PST1file(pswriter.PSresource):
  38
  39     """ PostScript font definition included in the prolog """
  40
  41     def __init__(self, t1file, glyphnames, charcodes):
  42         """ include type 1 font t1file stripped to the given glyphnames"""
  43         self.type = "t1file"
  44         self.t1file = t1file
  45         self.id = t1file.name
  46         self.glyphnames = set(glyphnames)
  47         self.charcodes = set(charcodes)
  48
  49     def merge(self, other):
  50         self.glyphnames.update(other.glyphnames)
  51         self.charcodes.update(other.charcodes)
  52
  53     def output(self, file, writer, registry):
  54         file.write("%%%%BeginFont: %s\n" % self.t1file.name)
  55         if writer.stripfonts:
  56             if self.glyphnames:
  57                 file.write("%%Included glyphs: %s\n" % " ".join(self.glyphnames))
  58             if self.charcodes:
  59                 file.write("%%Included charcodes: %s\n" % " ".join([str(charcode) for charcode in self.charcodes]))
  60             self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPS(file, writer)
  61         else:
  62             self.t1file.outputPS(file, writer)
  63         file.write("\n%%EndFont\n")
  64
  65
  66 _ReEncodeFont = pswriter.PSdefinition("ReEncodeFont", """{
  67   5 dict
  68   begin
  69     /newencoding exch def
  70     /newfontname exch def
  71     /basefontname exch def
  72     /basefontdict basefontname findfont def
  73     /newfontdict basefontdict maxlength dict def
  74     basefontdict {
  75       exch dup dup /FID ne exch /Encoding ne and
  76       { exch newfontdict 3 1 roll put }
  77       { pop pop }
  78       ifelse
  79     } forall
  80     newfontdict /FontName newfontname put
  81     newfontdict /Encoding newencoding put
  82     newfontname newfontdict definefont pop
  83   end
  84 }""")
  85
  86
  87 class PSreencodefont(pswriter.PSresource):
  88
  89     """ reencoded PostScript font"""
  90
  91     def __init__(self, basefontname, newfontname, encoding):
  92         """ reencode the font """
  93
  94         self.type = "reencodefont"
  95         self.basefontname = basefontname
  96         self.id = self.newfontname = newfontname
  97         self.encoding = encoding
  98
  99     def output(self, file, writer, registry):
 100         file.write("%%%%BeginResource: %s\n" % self.newfontname)
 101         file.write("/%s /%s\n[" % (self.basefontname, self.newfontname))
 102         vector = [None] * len(self.encoding)
 103         for glyphname, charcode in self.encoding.items():
 104             vector[charcode] = glyphname
 105         for i, glyphname in enumerate(vector):
 106             if i:
 107                 if not (i % 8):
 108                     file.write("\n")
 109                 else:
 110                     file.write(" ")
 111             file.write("/%s" % glyphname)
 112         file.write("]\n")
 113         file.write("ReEncodeFont\n")
 114         file.write("%%EndResource\n")
 115
 116
 117 _ChangeFontMatrix = pswriter.PSdefinition("ChangeFontMatrix", """{
 118   5 dict
 119   begin
 120     /newfontmatrix exch def
 121     /newfontname exch def
 122     /basefontname exch def
 123     /basefontdict basefontname findfont def
 124     /newfontdict basefontdict maxlength dict def
 125     basefontdict {
 126       exch dup dup /FID ne exch /FontMatrix ne and
 127       { exch newfontdict 3 1 roll put }
 128       { pop pop }
 129       ifelse
 130     } forall
 131     newfontdict /FontName newfontname put
 132     newfontdict /FontMatrix newfontmatrix readonly put
 133     newfontname newfontdict definefont pop
 134   end
 135 }""")
 136
 137
 138 class PSchangefontmatrix(pswriter.PSresource):
 139
 140     """ change font matrix of a PostScript font"""
 141
 142     def __init__(self, basefontname, newfontname, newfontmatrix):
 143         """ change the font matrix """
 144
 145         self.type = "changefontmatrix"
 146         self.basefontname = basefontname
 147         self.id = self.newfontname = newfontname
 148         self.newfontmatrix = newfontmatrix
 149
 150     def output(self, file, writer, registry):
 151         file.write("%%%%BeginResource: %s\n" % self.newfontname)
 152         file.write("/%s /%s\n" % (self.basefontname, self.newfontname))
 153         file.write(str(self.newfontmatrix))
 154         file.write("\nChangeFontMatrix\n")
 155         file.write("%%EndResource\n")
 156
 157
 158 ##############################################################################
 159 # PDF resources
 160 ##############################################################################
 161
 162 class PDFfont(pdfwriter.PDFobject):
 163
 164     def __init__(self, fontname, basefontname, charcodes, fontdescriptor, encoding, metric):
 165         pdfwriter.PDFobject.__init__(self, "font", fontname)
 166
 167         self.fontname = fontname
 168         self.basefontname = basefontname
 169         self.charcodes = set(charcodes)
 170         self.fontdescriptor = fontdescriptor
 171         self.encoding = encoding
 172         self.metric = metric
 173
 174     def merge(self, other):
 175         self.charcodes.update(other.charcodes)
 176
 177     def write(self, file, writer, registry):
 178         file.write("<<\n"
 179                    "/Type /Font\n"
 180                    "/Subtype /Type1\n")
 181         file.write("/Name /%s\n" % self.fontname)
 182         file.write("/BaseFont /%s\n" % self.basefontname)
 183         firstchar = min(self.charcodes)
 184         lastchar = max(self.charcodes)
 185         file.write("/FirstChar %d\n" % firstchar)
 186         file.write("/LastChar %d\n" % lastchar)
 187         file.write("/Widths\n"
 188                    "[")
 189         if self.encoding:
 190             encoding = self.encoding.getvector()
 191         else:
 192             encoding = self.fontdescriptor.fontfile.t1file.encoding
 193         for i in range(firstchar, lastchar+1):
 194             if i:
 195                 if not (i % 8):
 196                     file.write("\n")
 197                 else:
 198                     file.write(" ")
 199             if self.metric is not None:
 200                 file.write("%i" % self.metric.width_ds(encoding[i]))
 201             else:
 202                 file.write("%i" % self.fontdescriptor.fontfile.t1file.getglyphinfo(encoding[i])[0])
 203         file.write("]\n")
 204         file.write("/FontDescriptor %d 0 R\n" % registry.getrefno(self.fontdescriptor))
 205         if self.encoding:
 206             file.write("/Encoding %d 0 R\n" % registry.getrefno(self.encoding))
 207         file.write(">>\n")
 208
 209
 210 class PDFfontdescriptor(pdfwriter.PDFobject):
 211
 212     def __init__(self, fontname, fontfile, metric):
 213         pdfwriter.PDFobject.__init__(self, "fontdescriptor", fontname)
 214         self.fontname = fontname
 215         self.fontfile = fontfile
 216         self.metric = metric
 217
 218     def write(self, file, writer, registry):
 219         file.write("<<\n"
 220                    "/Type /FontDescriptor\n"
 221                    "/FontName /%s\n" % self.fontname)
 222         if self.metric is not None:
 223             self.metric.writePDFfontinfo(file)
 224         else:
 225             self.fontfile.t1file.writePDFfontinfo(file)
 226         if self.fontfile is not None:
 227             file.write("/FontFile %d 0 R\n" % registry.getrefno(self.fontfile))
 228         file.write(">>\n")
 229
 230
 231 class PDFfontfile(pdfwriter.PDFobject):
 232
 233     def __init__(self, t1file, glyphnames, charcodes):
 234         pdfwriter.PDFobject.__init__(self, "fontfile", t1file.name)
 235         self.t1file = t1file
 236         self.glyphnames = set(glyphnames)
 237         self.charcodes = set(charcodes)
 238
 239     def merge(self, other):
 240         self.glyphnames.update(other.glyphnames)
 241         self.charcodes.update(other.charcodes)
 242
 243     def write(self, file, writer, registry):
 244         if writer.stripfonts:
 245             self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPDF(file, writer)
 246         else:
 247             self.t1file.outputPDF(file, writer)
 248
 249
 250 class PDFencoding(pdfwriter.PDFobject):
 251
 252     def __init__(self, encoding, name):
 253         pdfwriter.PDFobject.__init__(self, "encoding", name)
 254         self.encoding = encoding
 255
 256     def getvector(self):
 257         # As self.encoding might be appended after the constructur has set it,
 258         # we need to defer the calculation until the whole content was constructed.
 259         vector = [None] * len(self.encoding)
 260         for glyphname, charcode in self.encoding.items():
 261             vector[charcode] = glyphname
 262         return vector
 263
 264     def write(self, file, writer, registry):
 265         file.write("<<\n"
 266                    "/Type /Encoding\n"
 267                    "/Differences\n"
 268                    "[0")
 269         for i, glyphname in enumerate(self.getvector()):
 270             if i:
 271                 if not (i % 8):
 272                     file.write("\n")
 273                 else:
 274                     file.write(" ")
 275             file.write("/%s" % glyphname)
 276         file.write("]\n"
 277                    ">>\n")
 278
 279
 280 ##############################################################################
 281 # basic PyX text output
 282 ##############################################################################
 283
 284 class font:
 285
 286     def text(self, x, y, charcodes, size_pt, **kwargs):
 287         return self.text_pt(unit.topt(x), unit.topt(y), charcodes, size_pt, **kwargs)
 288
 289
 290 class T1font(font):
 291
 292     def __init__(self, t1file, metric):
 293         self.t1file = t1file
 294         self.name = t1file.name
 295         self.metric = metric
 296
 297     def text_pt(self, x, y, charcodes, size_pt, **kwargs):
 298         return T1text_pt(self, x, y, charcodes, size_pt, **kwargs)
 299
 300
 301 class T1builtinfont(T1font):
 302
 303     def __init__(self, name, metric):
 304         self.name = name
 305         self.t1file = None
 306         self.metric = metric
 307
 308
 309 class selectedfont:
 310
 311     def __init__(self, name, size_pt):
 312         self.name = name
 313         self.size_pt = size_pt
 314
 315     def __ne__(self, other):
 316         return self.name != other.name or self.size_pt != other.size_pt
 317
 318     def outputPS(self, file, writer):
 319         file.write("/%s %f selectfont\n" % (self.name, self.size_pt))
 320
 321     def outputPDF(self, file, writer):
 322         file.write("/%s %f Tf\n" % (self.name, self.size_pt))
 323
 324
 325 class text_pt(canvasitem.canvasitem):
 326
 327     pass
 328
 329
 330 class T1text_pt(text_pt):
 331
 332     def __init__(self, font, x_pt, y_pt, charcodes, size_pt, decoding=None, slant=None, ignorebbox=False, kerning=False, ligatures=False):
 333         if decoding is not None:
 334             self.glyphnames = [decoding[character] for character in charcodes]
 335             self.decode = True
 336         else:
 337             self.charcodes = charcodes
 338             self.decode = False
 339         self.font = font
 340         self.x_pt = x_pt
 341         self.y_pt = y_pt
 342         self.size_pt = size_pt
 343         self.slant = slant
 344         self.ignorebbox = ignorebbox
 345         self.kerning = kerning
 346         self.ligatures = ligatures
 347
 348         if self.kerning and not self.decode:
 349             raise ValueError("decoding required for font metric access (kerning)")
 350         if self.ligatures and not self.decode:
 351             raise ValueError("decoding required for font metric access (ligatures)")
 352         if self.ligatures:
 353             self.glyphnames = self.font.metric.resolveligatures(self.glyphnames)
 354
 355     def bbox(self):
 356         if self.font.metric is None:
 357             raise ValueError("metric missing")
 358         if not self.decode:
 359             raise ValueError("decoding required for font metric access (bbox)")
 360         return bbox.bbox_pt(self.x_pt,
 361                             self.y_pt+self.font.metric.depth_pt(self.glyphnames, self.size_pt),
 362                             self.x_pt+self.font.metric.width_pt(self.glyphnames, self.size_pt),
 363                             self.y_pt+self.font.metric.height_pt(self.glyphnames, self.size_pt))
 364
 365     def getencodingname(self, encodings):
 366         """returns the name of the encoding (in encodings) mapping self.glyphnames to codepoints
 367         If no such encoding can be found or extended, a new encoding is added to encodings
 368         """
 369         glyphnames = set(self.glyphnames)
 370         if len(glyphnames) > 256:
 371             raise ValueError("glyphs do not fit into one single encoding")
 372         for encodingname, encoding in encodings.items():
 373             glyphsmissing = []
 374             for glyphname in glyphnames:
 375                 if glyphname not in encoding.keys():
 376                     glyphsmissing.append(glyphname)
 377
 378             if len(glyphsmissing) + len(encoding) < 256:
 379                 # new glyphs fit in existing encoding which will thus be extended
 380                 for glyphname in glyphsmissing:
 381                     encoding[glyphname] = len(encoding)
 382                 return encodingname
 383         # create a new encoding for the glyphnames
 384         encodingname = "encoding%d" % len(encodings)
 385         encodings[encodingname] = dict([(glyphname, i) for i, glyphname in enumerate(glyphnames)])
 386         return encodingname
 387
 388     def processPS(self, file, writer, context, registry, bbox):
 389         if not self.ignorebbox:
 390             bbox += self.bbox()
 391
 392         if writer.textaspath:
 393             if self.decode:
 394                 if self.kerning:
 395                     data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
 396                 else:
 397                     data = self.glyphnames
 398             else:
 399                 data = self.charcodes
 400             textpath = path.path()
 401             for i, value in enumerate(data):
 402                 if self.kerning and i % 2:
 403                     if value is not None:
 404                         self.x_pt += value
 405                 else:
 406                     glyphpath, wx_pt, wy_pt = self.font.t1file.getglyphpathwxwy_pt(value, self.size_pt, convertcharcode=not self.decode)
 407                     textpath += glyphpath.transformed(trafo.translate_pt(self.x_pt, self.y_pt))
 408                     self.x_pt += wx_pt
 409                     self.y_pt += wy_pt
 410             deco.decoratedpath(textpath, fillstyles=[]).processPS(file, writer, context, registry, bbox)
 411         else:
 412             # register resources
 413             if self.font.t1file is not None:
 414                 if self.decode:
 415                     registry.add(PST1file(self.font.t1file, self.glyphnames, []))
 416                 else:
 417                     registry.add(PST1file(self.font.t1file, [], self.charcodes))
 418
 419             fontname = self.font.name
 420             if self.decode:
 421                 encodingname = self.getencodingname(context.encodings.setdefault(self.font.name, {}))
 422                 encoding = context.encodings[self.font.name][encodingname]
 423                 newfontname = "%s-%s" % (fontname, encodingname)
 424                 registry.add(_ReEncodeFont)
 425                 registry.add(PSreencodefont(fontname, newfontname, encoding))
 426                 fontname = newfontname
 427
 428             if self.slant:
 429                 newfontmatrix = trafo.trafo_pt(matrix=((1, self.slant), (0, 1))) * self.font.t1file.fontmatrix
 430                 newfontname = "%s-slant%f" % (fontname, self.slant)
 431                 registry.add(_ChangeFontMatrix)
 432                 registry.add(PSchangefontmatrix(fontname, newfontname, newfontmatrix))
 433                 fontname = newfontname
 434
 435             # select font if necessary
 436             sf = selectedfont(fontname, self.size_pt)
 437             if context.selectedfont is None or sf != context.selectedfont:
 438                 context.selectedfont = sf
 439                 sf.outputPS(file, writer)
 440
 441             file.write("%f %f moveto (" % (self.x_pt, self.y_pt))
 442             if self.decode:
 443                 if self.kerning:
 444                     data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
 445                 else:
 446                     data = self.glyphnames
 447             else:
 448                 data = self.charcodes
 449             for i, value in enumerate(data):
 450                 if self.kerning and i % 2:
 451                     if value is not None:
 452                         file.write(") show\n%f 0 rmoveto (" % value)
 453                 else:
 454                     if self.decode:
 455                         value = encoding[value]
 456                     if 32 < value < 127 and chr(value) not in "()[]<>\\":
 457                         file.write("%s" % chr(value))
 458                     else:
 459                         file.write("\\%03o" % value)
 460             file.write(") show\n")
 461
 462     def processPDF(self, file, writer, context, registry, bbox):
 463         if not self.ignorebbox:
 464             bbox += self.bbox()
 465
 466         if writer.textaspath:
 467             if self.decode:
 468                 if self.kerning:
 469                     data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
 470                 else:
 471                     data = self.glyphnames
 472             else:
 473                 data = self.charcodes
 474             textpath = path.path()
 475             for i, value in enumerate(data):
 476                 if self.kerning and i % 2:
 477                     if value is not None:
 478                         self.x_pt += value
 479                 else:
 480                     glyphpath, wx_pt, wy_pt = self.font.t1file.getglyphpathwxwy_pt(value, self.size_pt, convertcharcode=not self.decode)
 481                     textpath += glyphpath.transformed(trafo.translate_pt(self.x_pt, self.y_pt))
 482                     self.x_pt += wx_pt
 483                     self.y_pt += wy_pt
 484             deco.decoratedpath(textpath, fillstyles=[]).processPDF(file, writer, context, registry, bbox)
 485         else:
 486             if self.decode:
 487                 encodingname = self.getencodingname(context.encodings.setdefault(self.font.name, {}))
 488                 encoding = context.encodings[self.font.name][encodingname]
 489                 charcodes = [encoding[glyphname] for glyphname in self.glyphnames]
 490             else:
 491                 charcodes = self.charcodes
 492
 493             # create resources
 494             fontname = self.font.name
 495             if self.decode:
 496                 newfontname = "%s-%s" % (fontname, encodingname)
 497                 _encoding = PDFencoding(encoding, newfontname)
 498                 fontname = newfontname
 499             else:
 500                 _encoding = None
 501             if self.font.t1file is not None:
 502                 if self.decode:
 503                     fontfile = PDFfontfile(self.font.t1file, self.glyphnames, [])
 504                 else:
 505                     fontfile = PDFfontfile(self.font.t1file, [], self.charcodes)
 506             else:
 507                 fontfile = None
 508             fontdescriptor = PDFfontdescriptor(self.font.name, fontfile, self.font.metric)
 509             font = PDFfont(fontname, self.font.name, charcodes, fontdescriptor, _encoding, self.font.metric)
 510
 511             # register resources
 512             if fontfile is not None:
 513                 registry.add(fontfile)
 514             registry.add(fontdescriptor)
 515             if _encoding is not None:
 516                 registry.add(_encoding)
 517             registry.add(font)
 518
 519             registry.addresource("Font", fontname, font, procset="Text")
 520
 521             if self.slant is None:
 522                 slantvalue = 0
 523             else:
 524                 slantvalue = self.slant
 525
 526             # select font if necessary
 527             sf = selectedfont(fontname, self.size_pt)
 528             if context.selectedfont is None or sf != context.selectedfont:
 529                 context.selectedfont = sf
 530                 sf.outputPDF(file, writer)
 531
 532             if self.kerning:
 533                 file.write("1 0 %f 1 %f %f Tm [(" % (slantvalue, self.x_pt, self.y_pt))
 534             else:
 535                 file.write("1 0 %f 1 %f %f Tm (" % (slantvalue, self.x_pt, self.y_pt))
 536             if self.decode:
 537                 if self.kerning:
 538                     data = self.font.metric.resolvekernings(self.glyphnames)
 539                 else:
 540                     data = self.glyphnames
 541             else:
 542                 data = self.charcodes
 543             for i, value in enumerate(data):
 544                 if self.kerning and i % 2:
 545                     if value is not None:
 546                         file.write(")%f(" % (-value))
 547                 else:
 548                     if self.decode:
 549                         value = encoding[value]
 550                     if 32 <= value <= 127 and chr(value) not in "()[]<>\\":
 551                         file.write("%s" % chr(value))
 552                     else:
 553                         file.write("\\%03o" % value)
 554             if self.kerning:
 555                 file.write(")] TJ\n")
 556             else:
 557                 file.write(") Tj\n")