pyx/font/font.py

   1 # -*- encoding: utf-8 -*-
   2 #
   3 #
   4 # Copyright (C) 2005-2011 Jörg Lehmann <joergl@users.sourceforge.net>
   5 # Copyright (C) 2006-2011 Michael Schindler <m-schindler@users.sourceforge.net>
   6 # Copyright (C) 2005-2011 André Wobst <wobsta@users.sourceforge.net>
   7 #
   8 # This file is part of PyX (http://pyx.sourceforge.net/).
   9 #
  10 # PyX is free software; you can redistribute it and/or modify
  11 # it under the terms of the GNU General Public License as published by
  12 # the Free Software Foundation; either version 2 of the License, or
  13 # (at your option) any later version.
  14 #
  15 # PyX is distributed in the hope that it will be useful,
  16 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 # GNU General Public License for more details.
  19 #
  20 # You should have received a copy of the GNU General Public License
  21 # along with PyX; if not, write to the Free Software
  22 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  23
  24 from pyx import bbox, canvasitem, deco, path, pswriter, pdfwriter, trafo, unit
  25 import t1file
  26
  27 try:
  28     set()
  29 except NameError:
  30     # Python 2.3
  31     from sets import Set as set
  32
  33
  34 ##############################################################################
  35 # PS resources
  36 ##############################################################################
  37
  38 class PST1file(pswriter.PSresource):
  39
  40     """ PostScript font definition included in the prolog """
  41
  42     def __init__(self, t1file, glyphnames, charcodes):
  43         """ include type 1 font t1file stripped to the given glyphnames"""
  44         self.type = "t1file"
  45         self.t1file = t1file
  46         self.id = t1file.name
  47         self.glyphnames = set(glyphnames)
  48         self.charcodes = set(charcodes)
  49
  50     def merge(self, other):
  51         self.glyphnames.update(other.glyphnames)
  52         self.charcodes.update(other.charcodes)
  53
  54     def output(self, file, writer, registry):
  55         file.write("%%%%BeginFont: %s\n" % self.t1file.name)
  56         if writer.strip_fonts:
  57             if self.glyphnames:
  58                 file.write("%%Included glyphs: %s\n" % " ".join(self.glyphnames))
  59             if self.charcodes:
  60                 file.write("%%Included charcodes: %s\n" % " ".join([str(charcode) for charcode in self.charcodes]))
  61             self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPS(file, writer)
  62         else:
  63             self.t1file.outputPS(file, writer)
  64         file.write("\n%%EndFont\n")
  65
  66
  67 _ReEncodeFont = pswriter.PSdefinition("ReEncodeFont", """{
  68   5 dict
  69   begin
  70     /newencoding exch def
  71     /newfontname exch def
  72     /basefontname exch def
  73     /basefontdict basefontname findfont def
  74     /newfontdict basefontdict maxlength dict def
  75     basefontdict {
  76       exch dup dup /FID ne exch /Encoding ne and
  77       { exch newfontdict 3 1 roll put }
  78       { pop pop }
  79       ifelse
  80     } forall
  81     newfontdict /FontName newfontname put
  82     newfontdict /Encoding newencoding put
  83     newfontname newfontdict definefont pop
  84   end
  85 }""")
  86
  87
  88 class PSreencodefont(pswriter.PSresource):
  89
  90     """ reencoded PostScript font"""
  91
  92     def __init__(self, basefontname, newfontname, encoding):
  93         """ reencode the font """
  94
  95         self.type = "reencodefont"
  96         self.basefontname = basefontname
  97         self.id = self.newfontname = newfontname
  98         self.encoding = encoding
  99
 100     def output(self, file, writer, registry):
 101         file.write("%%%%BeginResource: %s\n" % self.newfontname)
 102         file.write("/%s /%s\n[" % (self.basefontname, self.newfontname))
 103         vector = [None] * len(self.encoding)
 104         for glyphname, charcode in self.encoding.items():
 105             vector[charcode] = glyphname
 106         for i, glyphname in enumerate(vector):
 107             if i:
 108                 if not (i % 8):
 109                     file.write("\n")
 110                 else:
 111                     file.write(" ")
 112             file.write("/%s" % glyphname)
 113         file.write("]\n")
 114         file.write("ReEncodeFont\n")
 115         file.write("%%EndResource\n")
 116
 117
 118 _ChangeFontMatrix = pswriter.PSdefinition("ChangeFontMatrix", """{
 119   5 dict
 120   begin
 121     /newfontmatrix exch def
 122     /newfontname exch def
 123     /basefontname exch def
 124     /basefontdict basefontname findfont def
 125     /newfontdict basefontdict maxlength dict def
 126     basefontdict {
 127       exch dup dup /FID ne exch /FontMatrix ne and
 128       { exch newfontdict 3 1 roll put }
 129       { pop pop }
 130       ifelse
 131     } forall
 132     newfontdict /FontName newfontname put
 133     newfontdict /FontMatrix newfontmatrix readonly put
 134     newfontname newfontdict definefont pop
 135   end
 136 }""")
 137
 138
 139 class PSchangefontmatrix(pswriter.PSresource):
 140
 141     """ change font matrix of a PostScript font"""
 142
 143     def __init__(self, basefontname, newfontname, newfontmatrix):
 144         """ change the font matrix """
 145
 146         self.type = "changefontmatrix"
 147         self.basefontname = basefontname
 148         self.id = self.newfontname = newfontname
 149         self.newfontmatrix = newfontmatrix
 150
 151     def output(self, file, writer, registry):
 152         file.write("%%%%BeginResource: %s\n" % self.newfontname)
 153         file.write("/%s /%s\n" % (self.basefontname, self.newfontname))
 154         file.write(str(self.newfontmatrix))
 155         file.write("\nChangeFontMatrix\n")
 156         file.write("%%EndResource\n")
 157
 158
 159 ##############################################################################
 160 # PDF resources
 161 ##############################################################################
 162
 163 class PDFfont(pdfwriter.PDFobject):
 164
 165     def __init__(self, fontname, basefontname, charcodes, fontdescriptor, encoding, metric):
 166         pdfwriter.PDFobject.__init__(self, "font", fontname)
 167
 168         self.fontname = fontname
 169         self.basefontname = basefontname
 170         self.charcodes = set(charcodes)
 171         self.fontdescriptor = fontdescriptor
 172         self.encoding = encoding
 173         self.metric = metric
 174
 175     def merge(self, other):
 176         self.charcodes.update(other.charcodes)
 177
 178     def write(self, file, writer, registry):
 179         file.write("<<\n"
 180                    "/Type /Font\n"
 181                    "/Subtype /Type1\n")
 182         file.write("/Name /%s\n" % self.fontname)
 183         file.write("/BaseFont /%s\n" % self.basefontname)
 184         firstchar = min(self.charcodes)
 185         lastchar = max(self.charcodes)
 186         file.write("/FirstChar %d\n" % firstchar)
 187         file.write("/LastChar %d\n" % lastchar)
 188         file.write("/Widths\n"
 189                    "[")
 190         if self.encoding:
 191             encoding = self.encoding.getvector()
 192         else:
 193             encoding = self.fontdescriptor.fontfile.t1file.encoding
 194         for i in range(firstchar, lastchar+1):
 195             if i:
 196                 if not (i % 8):
 197                     file.write("\n")
 198                 else:
 199                     file.write(" ")
 200             if i in self.charcodes:
 201                 if self.metric is not None:
 202                     file.write("%i" % self.metric.width_ds(encoding[i]))
 203                 else:
 204                     file.write("%i" % self.fontdescriptor.fontfile.t1file.getglyphinfo(encoding[i])[0])
 205             else:
 206                 file.write("0")
 207         file.write(" ]\n")
 208         file.write("/FontDescriptor %d 0 R\n" % registry.getrefno(self.fontdescriptor))
 209         if self.encoding:
 210             file.write("/Encoding %d 0 R\n" % registry.getrefno(self.encoding))
 211         file.write(">>\n")
 212
 213
 214 class PDFstdfont(pdfwriter.PDFobject):
 215
 216     def __init__(self, basename):
 217         pdfwriter.PDFobject.__init__(self, "font", "stdfont-%s" % basename)
 218         self.name = basename # name is ignored by acroread
 219         self.basename = basename
 220
 221     def write(self, file, writer, registry):
 222         file.write("<</BaseFont /%s\n" % self.basename)
 223         file.write("/Name /%s\n" % self.name)
 224         file.write("/Type /Font\n")
 225         file.write("/Subtype /Type1\n")
 226         file.write(">>\n")
 227
 228 # the 14 standard fonts that are always available in PDF
 229 PDFTimesRoman           = PDFstdfont("Times-Roman")
 230 PDFTimesBold            = PDFstdfont("Times-Bold")
 231 PDFTimesItalic          = PDFstdfont("Times-Italic")
 232 PDFTimesBoldItalic      = PDFstdfont("Times-BoldItalic")
 233 PDFHelvetica            = PDFstdfont("Helvetica")
 234 PDFHelveticaBold        = PDFstdfont("Helvetica-Bold")
 235 PDFHelveticaOblique     = PDFstdfont("Helvetica-Oblique")
 236 PDFHelveticaBoldOblique = PDFstdfont("Helvetica-BoldOblique")
 237 PDFCourier              = PDFstdfont("Courier")
 238 PDFCourierBold          = PDFstdfont("Courier-Bold")
 239 PDFCourierOblique       = PDFstdfont("Courier-Oblique")
 240 PDFCourierBoldOblique   = PDFstdfont("Courier-BoldOblique")
 241 PDFSymbol               = PDFstdfont("Symbol")
 242 PDFZapfDingbats         = PDFstdfont("ZapfDingbats")
 243
 244
 245 class PDFfontdescriptor(pdfwriter.PDFobject):
 246
 247     def __init__(self, fontname, fontfile, metric):
 248         pdfwriter.PDFobject.__init__(self, "fontdescriptor", fontname)
 249         self.fontname = fontname
 250         self.fontfile = fontfile
 251         self.metric = metric
 252
 253     def write(self, file, writer, registry):
 254         file.write("<<\n"
 255                    "/Type /FontDescriptor\n"
 256                    "/FontName /%s\n" % self.fontname)
 257         if self.metric is not None:
 258             self.metric.writePDFfontinfo(file)
 259         else:
 260             self.fontfile.t1file.writePDFfontinfo(file)
 261         if self.fontfile is not None:
 262             file.write("/FontFile %d 0 R\n" % registry.getrefno(self.fontfile))
 263         file.write(">>\n")
 264
 265
 266 class PDFfontfile(pdfwriter.PDFobject):
 267
 268     def __init__(self, t1file, glyphnames, charcodes):
 269         pdfwriter.PDFobject.__init__(self, "fontfile", t1file.name)
 270         self.t1file = t1file
 271         self.glyphnames = set(glyphnames)
 272         self.charcodes = set(charcodes)
 273
 274     def merge(self, other):
 275         self.glyphnames.update(other.glyphnames)
 276         self.charcodes.update(other.charcodes)
 277
 278     def write(self, file, writer, registry):
 279         if writer.strip_fonts:
 280             self.t1file.getstrippedfont(self.glyphnames, self.charcodes).outputPDF(file, writer)
 281         else:
 282             self.t1file.outputPDF(file, writer)
 283
 284
 285 class PDFencoding(pdfwriter.PDFobject):
 286
 287     def __init__(self, encoding, name):
 288         pdfwriter.PDFobject.__init__(self, "encoding", name)
 289         self.encoding = encoding
 290
 291     def getvector(self):
 292         # As self.encoding might be appended after the constructur has set it,
 293         # we need to defer the calculation until the whole content was constructed.
 294         vector = [None] * len(self.encoding)
 295         for glyphname, charcode in self.encoding.items():
 296             vector[charcode] = glyphname
 297         return vector
 298
 299     def write(self, file, writer, registry):
 300         file.write("<<\n"
 301                    "/Type /Encoding\n"
 302                    "/Differences\n"
 303                    "[0")
 304         for i, glyphname in enumerate(self.getvector()):
 305             if i:
 306                 if not (i % 8):
 307                     file.write("\n")
 308                 else:
 309                     file.write(" ")
 310             file.write("/%s" % glyphname)
 311         file.write("]\n"
 312                    ">>\n")
 313
 314
 315 ##############################################################################
 316 # basic PyX text output
 317 ##############################################################################
 318
 319 class font:
 320
 321     def text(self, x, y, charcodes, size_pt, **kwargs):
 322         return self.text_pt(unit.topt(x), unit.topt(y), charcodes, size_pt, **kwargs)
 323
 324
 325 class T1font(font):
 326
 327     def __init__(self, t1file, metric):
 328         self.t1file = t1file
 329         self.name = t1file.name
 330         self.metric = metric
 331
 332     def text_pt(self, x, y, charcodes, size_pt, **kwargs):
 333         return T1text_pt(self, x, y, charcodes, size_pt, **kwargs)
 334
 335
 336 class T1builtinfont(T1font):
 337
 338     def __init__(self, name, metric):
 339         self.name = name
 340         self.t1file = None
 341         self.metric = metric
 342
 343
 344 class selectedfont:
 345
 346     def __init__(self, name, size_pt):
 347         self.name = name
 348         self.size_pt = size_pt
 349
 350     def __ne__(self, other):
 351         return self.name != other.name or self.size_pt != other.size_pt
 352
 353     def outputPS(self, file, writer):
 354         file.write("/%s %f selectfont\n" % (self.name, self.size_pt))
 355
 356     def outputPDF(self, file, writer):
 357         file.write("/%s %f Tf\n" % (self.name, self.size_pt))
 358
 359
 360 class text_pt(canvasitem.canvasitem):
 361
 362     pass
 363
 364
 365 class T1text_pt(text_pt):
 366
 367     def __init__(self, font, x_pt, y_pt, charcodes, size_pt, decoding=None, slant=None, ignorebbox=False, kerning=False, ligatures=False, spaced_pt=0):
 368         if decoding is not None:
 369             self.glyphnames = [decoding[character] for character in charcodes]
 370             self.decode = True
 371         else:
 372             self.charcodes = charcodes
 373             self.decode = False
 374         self.font = font
 375         self.x_pt = x_pt
 376         self.y_pt = y_pt
 377         self.size_pt = size_pt
 378         self.slant = slant
 379         self.ignorebbox = ignorebbox
 380         self.kerning = kerning
 381         self.ligatures = ligatures
 382         self.spaced_pt = spaced_pt
 383
 384         if self.kerning and not self.decode:
 385             raise ValueError("decoding required for font metric access (kerning)")
 386         if self.ligatures and not self.decode:
 387             raise ValueError("decoding required for font metric access (ligatures)")
 388         if self.ligatures:
 389             self.glyphnames = self.font.metric.resolveligatures(self.glyphnames)
 390
 391     def bbox(self):
 392         if self.font.metric is None:
 393             raise ValueError("metric missing")
 394         if not self.decode:
 395             raise ValueError("decoding required for font metric access (bbox)")
 396         return bbox.bbox_pt(self.x_pt,
 397                             self.y_pt+self.font.metric.depth_pt(self.glyphnames, self.size_pt),
 398                             self.x_pt+self.font.metric.width_pt(self.glyphnames, self.size_pt),
 399                             self.y_pt+self.font.metric.height_pt(self.glyphnames, self.size_pt))
 400
 401     def getencodingname(self, encodings):
 402         """returns the name of the encoding (in encodings) mapping self.glyphnames to codepoints
 403         If no such encoding can be found or extended, a new encoding is added to encodings
 404         """
 405         glyphnames = set(self.glyphnames)
 406         if len(glyphnames) > 256:
 407             raise ValueError("glyphs do not fit into one single encoding")
 408         for encodingname, encoding in encodings.items():
 409             glyphsmissing = []
 410             for glyphname in glyphnames:
 411                 if glyphname not in encoding.keys():
 412                     glyphsmissing.append(glyphname)
 413
 414             if len(glyphsmissing) + len(encoding) < 256:
 415                 # new glyphs fit in existing encoding which will thus be extended
 416                 for glyphname in glyphsmissing:
 417                     encoding[glyphname] = len(encoding)
 418                 return encodingname
 419         # create a new encoding for the glyphnames
 420         encodingname = "encoding%d" % len(encodings)
 421         encodings[encodingname] = dict([(glyphname, i) for i, glyphname in enumerate(glyphnames)])
 422         return encodingname
 423
 424     def textpath(self):
 425         if self.decode:
 426             if self.kerning:
 427                 data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
 428             else:
 429                 data = self.glyphnames
 430         else:
 431             data = self.charcodes
 432         textpath = path.path()
 433         x_pt = self.x_pt
 434         y_pt = self.y_pt
 435         for i, value in enumerate(data):
 436             if self.kerning and i % 2:
 437                 if value is not None:
 438                     x_pt += value
 439             else:
 440                 if i:
 441                     x_pt += self.spaced_pt
 442                 glyphpath, wx_pt, wy_pt = self.font.t1file.getglyphpathwxwy_pt(value, self.size_pt, convertcharcode=not self.decode)
 443                 textpath += glyphpath.transformed(trafo.translate_pt(x_pt, y_pt))
 444                 x_pt += wx_pt
 445                 y_pt += wy_pt
 446         return textpath
 447
 448     def processPS(self, file, writer, context, registry, bbox):
 449         if not self.ignorebbox:
 450             bbox += self.bbox()
 451
 452         if writer.text_as_path:
 453             deco.decoratedpath(self.textpath(), fillstyles=[]).processPS(file, writer, context, registry, bbox)
 454         else:
 455             # register resources
 456             if self.font.t1file is not None:
 457                 if self.decode:
 458                     registry.add(PST1file(self.font.t1file, self.glyphnames, []))
 459                 else:
 460                     registry.add(PST1file(self.font.t1file, [], self.charcodes))
 461
 462             fontname = self.font.name
 463             if self.decode:
 464                 encodingname = self.getencodingname(writer.encodings.setdefault(self.font.name, {}))
 465                 encoding = writer.encodings[self.font.name][encodingname]
 466                 newfontname = "%s-%s" % (fontname, encodingname)
 467                 registry.add(_ReEncodeFont)
 468                 registry.add(PSreencodefont(fontname, newfontname, encoding))
 469                 fontname = newfontname
 470
 471             if self.slant:
 472                 newfontmatrix = trafo.trafo_pt(matrix=((1, self.slant), (0, 1)))
 473                 if self.font.t1file is not None:
 474                     newfontmatrix = newfontmatrix * self.font.t1file.fontmatrix
 475                 newfontname = "%s-slant%f" % (fontname, self.slant)
 476                 registry.add(_ChangeFontMatrix)
 477                 registry.add(PSchangefontmatrix(fontname, newfontname, newfontmatrix))
 478                 fontname = newfontname
 479
 480             # select font if necessary
 481             sf = selectedfont(fontname, self.size_pt)
 482             if context.selectedfont is None or sf != context.selectedfont:
 483                 context.selectedfont = sf
 484                 sf.outputPS(file, writer)
 485
 486             file.write("%f %f moveto (" % (self.x_pt, self.y_pt))
 487             if self.decode:
 488                 if self.kerning:
 489                     data = self.font.metric.resolvekernings(self.glyphnames, self.size_pt)
 490                 else:
 491                     data = self.glyphnames
 492             else:
 493                 data = self.charcodes
 494             for i, value in enumerate(data):
 495                 if self.kerning and i % 2:
 496                     if value is not None:
 497                         file.write(") show\n%f 0 rmoveto (" % (value+self.spaced_pt))
 498                     elif self.spaced_pt:
 499                         file.write(") show\n%f 0 rmoveto (" % self.spaced_pt)
 500                 else:
 501                     if i and not self.kerning and self.spaced_pt:
 502                         file.write(") show\n%f 0 rmoveto (" % self.spaced_pt)
 503                     if self.decode:
 504                         value = encoding[value]
 505                     if 32 < value < 127 and chr(value) not in "()[]<>\\":
 506                         file.write("%s" % chr(value))
 507                     else:
 508                         file.write("\\%03o" % value)
 509             file.write(") show\n")
 510
 511     def processPDF(self, file, writer, context, registry, bbox):
 512         if not self.ignorebbox:
 513             bbox += self.bbox()
 514
 515         if writer.text_as_path:
 516             deco.decoratedpath(self.textpath(), fillstyles=[]).processPDF(file, writer, context, registry, bbox)
 517         else:
 518             if self.decode:
 519                 encodingname = self.getencodingname(writer.encodings.setdefault(self.font.name, {}))
 520                 encoding = writer.encodings[self.font.name][encodingname]
 521                 charcodes = [encoding[glyphname] for glyphname in self.glyphnames]
 522             else:
 523                 charcodes = self.charcodes
 524
 525             # create resources
 526             fontname = self.font.name
 527             if self.decode:
 528                 newfontname = "%s-%s" % (fontname, encodingname)
 529                 _encoding = PDFencoding(encoding, newfontname)
 530                 fontname = newfontname
 531             else:
 532                 _encoding = None
 533             if self.font.t1file is not None:
 534                 if self.decode:
 535                     fontfile = PDFfontfile(self.font.t1file, self.glyphnames, [])
 536                 else:
 537                     fontfile = PDFfontfile(self.font.t1file, [], self.charcodes)
 538             else:
 539                 fontfile = None
 540             fontdescriptor = PDFfontdescriptor(self.font.name, fontfile, self.font.metric)
 541             font = PDFfont(fontname, self.font.name, charcodes, fontdescriptor, _encoding, self.font.metric)
 542
 543             # register resources
 544             if fontfile is not None:
 545                 registry.add(fontfile)
 546             registry.add(fontdescriptor)
 547             if _encoding is not None:
 548                 registry.add(_encoding)
 549             registry.add(font)
 550
 551             registry.addresource("Font", fontname, font, procset="Text")
 552
 553             if self.slant is None:
 554                 slantvalue = 0
 555             else:
 556                 slantvalue = self.slant
 557
 558             # select font if necessary
 559             sf = selectedfont(fontname, self.size_pt)
 560             if context.selectedfont is None or sf != context.selectedfont:
 561                 context.selectedfont = sf
 562                 sf.outputPDF(file, writer)
 563
 564             if self.kerning:
 565                 file.write("1 0 %f 1 %f %f Tm [(" % (slantvalue, self.x_pt, self.y_pt))
 566             else:
 567                 file.write("1 0 %f 1 %f %f Tm (" % (slantvalue, self.x_pt, self.y_pt))
 568             if self.decode:
 569                 if self.kerning:
 570                     data = self.font.metric.resolvekernings(self.glyphnames)
 571                 else:
 572                     data = self.glyphnames
 573             else:
 574                 data = self.charcodes
 575             for i, value in enumerate(data):
 576                 if self.kerning and i % 2:
 577                     if value is not None:
 578                         file.write(")%f(" % (-value-self.spaced_pt))
 579                     elif self.spaced_pt:
 580                         file.write(")%f(" % (-self.spaced_pt))
 581                 else:
 582                     if i and not self.kerning and self.spaced_pt:
 583                         file.write(")%f(" % (-self.spaced_pt))
 584                     if self.decode:
 585                         value = encoding[value]
 586                     if 32 <= value <= 127 and chr(value) not in "()[]<>\\":
 587                         file.write("%s" % chr(value))
 588                     else:
 589                         file.write("\\%03o" % value)
 590             if self.kerning:
 591                 file.write(")] TJ\n")
 592             else:
 593                 file.write(") Tj\n")