dvi/dvifile.py

   1 # -*- encoding: utf-8 -*-
   2 #
   3 #
   4 # Copyright (C) 2002-2011 Jörg Lehmann <joergl@users.sourceforge.net>
   5 # Copyright (C) 2003-2004,2006,2007 Michael Schindler <m-schindler@users.sourceforge.net>
   6 # Copyright (C) 2002-2011 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 import io, math, re, struct, sys, warnings
  25 from pyx import  bbox, canvas, color, epsfile, config, path, reader, trafo, unit
  26 from . import texfont, tfmfile
  27
  28
  29 _DVI_CHARMIN     =   0 # typeset a character and move right (range min)
  30 _DVI_CHARMAX     = 127 # typeset a character and move right (range max)
  31 _DVI_SET1234     = 128 # typeset a character and move right
  32 _DVI_SETRULE     = 132 # typeset a rule and move right
  33 _DVI_PUT1234     = 133 # typeset a character
  34 _DVI_PUTRULE     = 137 # typeset a rule
  35 _DVI_NOP         = 138 # no operation
  36 _DVI_BOP         = 139 # beginning of page
  37 _DVI_EOP         = 140 # ending of page
  38 _DVI_PUSH        = 141 # save the current positions (h, v, w, x, y, z)
  39 _DVI_POP         = 142 # restore positions (h, v, w, x, y, z)
  40 _DVI_RIGHT1234   = 143 # move right
  41 _DVI_W0          = 147 # move right by w
  42 _DVI_W1234       = 148 # move right and set w
  43 _DVI_X0          = 152 # move right by x
  44 _DVI_X1234       = 153 # move right and set x
  45 _DVI_DOWN1234    = 157 # move down
  46 _DVI_Y0          = 161 # move down by y
  47 _DVI_Y1234       = 162 # move down and set y
  48 _DVI_Z0          = 166 # move down by z
  49 _DVI_Z1234       = 167 # move down and set z
  50 _DVI_FNTNUMMIN   = 171 # set current font (range min)
  51 _DVI_FNTNUMMAX   = 234 # set current font (range max)
  52 _DVI_FNT1234     = 235 # set current font
  53 _DVI_SPECIAL1234 = 239 # special (dvi extention)
  54 _DVI_FNTDEF1234  = 243 # define the meaning of a font number
  55 _DVI_PRE         = 247 # preamble
  56 _DVI_POST        = 248 # postamble beginning
  57 _DVI_POSTPOST    = 249 # postamble ending
  58
  59 _DVI_VERSION     = 2   # dvi version
  60
  61 # position variable indices
  62 _POS_H           = 0
  63 _POS_V           = 1
  64 _POS_W           = 2
  65 _POS_X           = 3
  66 _POS_Y           = 4
  67 _POS_Z           = 5
  68
  69 # reader states
  70 _READ_PRE       = 1
  71 _READ_NOPAGE    = 2
  72 _READ_PAGE      = 3
  73 _READ_POST      = 4 # XXX not used
  74 _READ_POSTPOST  = 5 # XXX not used
  75 _READ_DONE      = 6
  76
  77
  78 class DVIError(Exception): pass
  79
  80
  81 class DVIfile:
  82
  83     def __init__(self, filename, debug=0, debugfile=sys.stdout):
  84         """ opens the dvi file and reads the preamble """
  85         self.filename = filename
  86         self.debug = debug
  87         self.debugfile = debugfile
  88         self.debugstack = []
  89
  90         self.fonts = {}
  91         self.activefont = None
  92
  93         # stack of fonts and fontscale currently used (used for VFs)
  94         self.fontstack = []
  95         self.stack = []
  96
  97         # pointer to currently active page
  98         self.actpage = None
  99
 100         # stack for self.file, self.fonts and self.stack, needed for VF inclusion
 101         self.statestack = []
 102
 103         self.file = reader.reader(self.filename)
 104
 105         # currently read byte in file (for debugging output)
 106         self.filepos = None
 107
 108         self._read_pre()
 109
 110     # helper routines
 111
 112     def beginsubpage(self, attrs):
 113         c = canvas.canvas(attrs)
 114         c.parent = self.actpage
 115         c.markers = {}
 116         self.actpage.insert(c)
 117         self.actpage = c
 118
 119     def endsubpage(self):
 120         for key, value in list(self.actpage.markers.items()):
 121             self.actpage.parent.markers[key] = self.actpage.trafo.apply(*value)
 122         self.actpage = self.actpage.parent
 123
 124     def flushtext(self, fontmap):
 125         """ finish currently active text object """
 126         if self.activetext:
 127             x, y, charcodes = self.activetext
 128             x_pt, y_pt = x * self.pyxconv, -y*self.pyxconv
 129             self.actpage.insert(self.activefont.text_pt(x_pt, y_pt, charcodes, fontmap=fontmap))
 130             if self.debug:
 131                 self.debugfile.write("[%s]\n" % "".join([chr(char) for char in self.activetext[2]]))
 132             self.activetext = None
 133
 134     def putrule(self, height, width, advancepos, fontmap):
 135         self.flushtext(fontmap)
 136         x1 =  self.pos[_POS_H] * self.pyxconv
 137         y1 = -self.pos[_POS_V] * self.pyxconv
 138         w = width * self.pyxconv
 139         h = height * self.pyxconv
 140
 141         if height > 0 and width > 0:
 142             if self.debug:
 143                 self.debugfile.write("%d: %srule height %d, width %d (???x??? pixels)\n" %
 144                                      (self.filepos, advancepos and "set" or "put", height, width))
 145             self.actpage.fill(path.rect_pt(x1, y1, w, h))
 146         else:
 147             if self.debug:
 148                 self.debugfile.write("%d: %srule height %d, width %d (invisible)\n" %
 149                                      (self.filepos, advancepos and "set" or "put", height, width))
 150
 151         if advancepos:
 152             if self.debug:
 153                 self.debugfile.write(" h:=%d+%d=%d, hh:=???\n" %
 154                                      (self.pos[_POS_H], width, self.pos[_POS_H]+width))
 155             self.pos[_POS_H] += width * self.scale
 156
 157     def putchar(self, char, advancepos, id1234, fontmap):
 158         dx = advancepos and self.activefont.getwidth_dvi(char) or 0
 159
 160         if self.debug:
 161             self.debugfile.write("%d: %s%s%d h:=%d+%d=%d, hh:=???\n" %
 162                                  (self.filepos,
 163                                   advancepos and "set" or "put",
 164                                   id1234 and "%i " % id1234 or "char",
 165                                   char,
 166                                   self.pos[_POS_H], dx, self.pos[_POS_H]+dx))
 167
 168         if isinstance(self.activefont, texfont.virtualfont):
 169             # virtual font handling
 170             afterpos = list(self.pos)
 171             afterpos[_POS_H] += dx
 172             self._push_dvistring(self.activefont.getchar(char), self.activefont.getfonts(), afterpos,
 173                                  self.activefont.getsize_pt(), fontmap)
 174         else:
 175             if self.activetext is None:
 176                 self.activetext = (self.pos[_POS_H], self.pos[_POS_V], [])
 177             self.activetext[2].append(char)
 178             self.pos[_POS_H] += dx
 179
 180         if (not advancepos) or self.singlecharmode:
 181             self.flushtext(fontmap)
 182
 183     def usefont(self, fontnum, id1234, fontmap):
 184         self.flushtext(fontmap)
 185         self.activefont = self.fonts[fontnum]
 186         if self.debug:
 187             self.debugfile.write("%d: fnt%s%i current font is %s\n" %
 188                                  (self.filepos,
 189                                   id1234 and "%i " % id1234 or "num",
 190                                   fontnum,
 191                                   self.fonts[fontnum].name))
 192
 193
 194     def definefont(self, cmdnr, num, c, q, d, fontname):
 195         # cmdnr: type of fontdef command (only used for debugging output)
 196         # c:     checksum
 197         # q:     scaling factor (fix_word)
 198         #        Note that q is actually s in large parts of the documentation.
 199         # d:     design size (fix_word)
 200
 201         # check whether it's a virtual font by trying to open it. if this fails, it is an ordinary TeX font
 202         try:
 203             fontfile = config.open(fontname, [config.format.vf])
 204         except IOError:
 205             afont = texfont.TeXfont(fontname, c, q/self.tfmconv, d/self.tfmconv, self.tfmconv, self.pyxconv, self.debug>1)
 206         else:
 207             afont = texfont.virtualfont(fontname, fontfile, c, q/self.tfmconv, d/self.tfmconv, self.tfmconv, self.pyxconv, self.debug>1)
 208
 209         self.fonts[num] = afont
 210
 211         if self.debug:
 212             self.debugfile.write("%d: fntdef%d %i: %s\n" % (self.filepos, cmdnr, num, fontname))
 213
 214 #            scale = round((1000.0*self.conv*q)/(self.trueconv*d))
 215 #            m = 1.0*q/d
 216 #            scalestring = scale!=1000 and " scaled %d" % scale or ""
 217 #            print ("Font %i: %s%s---loaded at size %d DVI units" %
 218 #                   (num, fontname, scalestring, q))
 219 #            if scale!=1000:
 220 #                print " (this font is magnified %d%%)" % round(scale/10)
 221
 222     def special(self, s, fontmap):
 223         x =  self.pos[_POS_H] * self.pyxconv
 224         y = -self.pos[_POS_V] * self.pyxconv
 225         if self.debug:
 226             self.debugfile.write("%d: xxx '%s'\n" % (self.filepos, s))
 227         if not s.startswith("PyX:"):
 228             warnings.warn("ignoring special '%s'" % s)
 229             return
 230
 231         # it is in general not safe to continue using the currently active font because
 232         # the specials may involve some gsave/grestore operations
 233         self.flushtext(fontmap)
 234
 235         command, args = s[4:].split()[0], s[4:].split()[1:]
 236         if command == "color_begin":
 237             if args[0] == "cmyk":
 238                 c = color.cmyk(float(args[1]), float(args[2]), float(args[3]), float(args[4]))
 239             elif args[0] == "gray":
 240                 c = color.gray(float(args[1]))
 241             elif args[0] == "hsb":
 242                 c = color.hsb(float(args[1]), float(args[2]), float(args[3]))
 243             elif args[0] == "rgb":
 244                 c = color.rgb(float(args[1]), float(args[2]), float(args[3]))
 245             elif args[0] == "RGB":
 246                 c = color.rgb(int(args[1])/255.0, int(args[2])/255.0, int(args[3])/255.0)
 247             elif args[0] == "texnamed":
 248                 try:
 249                     c = getattr(color.cmyk, args[1])
 250                 except AttributeError:
 251                     raise RuntimeError("unknown TeX color '%s', aborting" % args[1])
 252             elif args[0] == "pyxcolor":
 253                 # pyx.color.cmyk.PineGreen or
 254                 # pyx.color.cmyk(0,0,0,0.0)
 255                 pat = re.compile(r"(pyx\.)?(color\.)?(?P<model>(cmyk)|(rgb)|(grey)|(gray)|(hsb))[\.]?(?P<arg>.*)")
 256                 sd = pat.match(" ".join(args[1:]))
 257                 if sd:
 258                     sd = sd.groupdict()
 259                     if sd["arg"][0] == "(":
 260                         numpat = re.compile(r"[+-]?((\d+\.\d*)|(\d*\.\d+)|(\d+))([eE][+-]\d+)?")
 261                         arg = tuple([float(x[0]) for x in numpat.findall(sd["arg"])])
 262                         try:
 263                             c = getattr(color, sd["model"])(*arg)
 264                         except TypeError or AttributeError:
 265                             raise RuntimeError("cannot access PyX color '%s' in TeX, aborting" % " ".join(args[1:]))
 266                     else:
 267                         try:
 268                             c = getattr(getattr(color, sd["model"]), sd["arg"])
 269                         except AttributeError:
 270                             raise RuntimeError("cannot access PyX color '%s' in TeX, aborting" % " ".join(args[1:]))
 271                 else:
 272                     raise RuntimeError("cannot access PyX color '%s' in TeX, aborting" % " ".join(args[1:]))
 273             else:
 274                 raise RuntimeError("color model '%s' cannot be handled by PyX, aborting" % args[0])
 275
 276             self.beginsubpage([c])
 277         elif command == "color_end":
 278             self.endsubpage()
 279         elif command == "rotate_begin":
 280             self.beginsubpage([trafo.rotate_pt(float(args[0]), x, y)])
 281         elif command == "rotate_end":
 282             self.endsubpage()
 283         elif command == "scale_begin":
 284             self.beginsubpage([trafo.scale_pt(float(args[0]), float(args[1]), x, y)])
 285         elif command == "scale_end":
 286             self.endsubpage()
 287         elif command == "epsinclude":
 288             # parse arguments
 289             argdict = {}
 290             for arg in args:
 291                 name, value = arg.split("=")
 292                 argdict[name] = value
 293
 294             # construct kwargs for epsfile constructor
 295             epskwargs = {}
 296             epskwargs["filename"] = argdict["file"]
 297             epskwargs["bbox"] = bbox.bbox_pt(float(argdict["llx"]), float(argdict["lly"]),
 298                                            float(argdict["urx"]), float(argdict["ury"]))
 299             if "width" in argdict:
 300                 epskwargs["width"] = float(argdict["width"]) * unit.t_pt
 301             if "height" in argdict:
 302                 epskwargs["height"] = float(argdict["height"]) * unit.t_pt
 303             if "clip" in argdict:
 304                epskwargs["clip"] = int(argdict["clip"])
 305             self.actpage.insert(epsfile.epsfile(x * unit.t_pt, y * unit.t_pt, **epskwargs))
 306         elif command == "marker":
 307             if len(args) != 1:
 308                 raise RuntimeError("marker contains spaces")
 309             for c in args[0]:
 310                 if c not in "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789@":
 311                     raise RuntimeError("marker contains invalid characters")
 312             if args[0] in self.actpage.markers:
 313                 raise RuntimeError("marker name occurred several times")
 314             self.actpage.markers[args[0]] = x * unit.t_pt, y * unit.t_pt
 315         else:
 316             raise RuntimeError("unknown PyX special '%s', aborting" % command)
 317
 318     # routines for pushing and popping different dvi chunks on the reader
 319
 320     def _push_dvistring(self, dvi, fonts, afterpos, fontsize, fontmap):
 321         """ push dvi string with defined fonts on top of reader
 322         stack. Every positions gets scaled relatively by the factor
 323         scale. After interpretating the dvi chunk, continue with self.pos=afterpos.
 324         The designsize of the virtual font is passed as a fix_word
 325
 326         """
 327
 328         #if self.debug:
 329         #    self.debugfile.write("executing new dvi chunk\n")
 330         self.debugstack.append(self.debug)
 331         self.debug = 0
 332
 333         self.statestack.append((self.file, self.fonts, self.activefont, afterpos, self.stack, self.scale))
 334
 335         # units in vf files are relative to the size of the font and given as fix_words
 336         # which can be converted to floats by diving by 2**20.
 337         # This yields the following scale factor for the height and width of rects:
 338         self.scale = fontsize/2**20/self.pyxconv
 339
 340         self.file = reader.bytesreader(dvi)
 341         self.fonts = fonts
 342         self.stack = []
 343         self.filepos = 0
 344
 345         self.usefont(0, 0, fontmap)
 346
 347     def _pop_dvistring(self, fontmap):
 348         self.flushtext(fontmap)
 349         #if self.debug:
 350         #    self.debugfile.write("finished executing dvi chunk\n")
 351         self.debug = self.debugstack.pop()
 352
 353         self.file.close()
 354         self.file, self.fonts, self.activefont, self.pos, self.stack, self.scale = self.statestack.pop()
 355
 356     # routines corresponding to the different reader states of the dvi maschine
 357
 358     def _read_pre(self):
 359         afile = self.file
 360         while True:
 361             self.filepos = afile.tell()
 362             cmd = afile.readuchar()
 363             if cmd == _DVI_NOP:
 364                 pass
 365             elif cmd == _DVI_PRE:
 366                 if afile.readuchar() != _DVI_VERSION: raise DVIError
 367                 num = afile.readuint32()
 368                 den = afile.readuint32()
 369                 self.mag = afile.readuint32()
 370
 371                 # For the interpretation of the lengths in dvi and tfm files,
 372                 # three conversion factors are relevant:
 373                 # - self.tfmconv: tfm units -> dvi units
 374                 # - self.pyxconv: dvi units -> (PostScript) points
 375                 # - self.conv:    dvi units -> pixels
 376                 self.tfmconv = (25400000.0/num)*(den/473628672.0)/16.0
 377
 378                 # calculate conv as described in the DVIType docu using
 379                 # a given resolution in dpi
 380                 self.resolution = 300.0
 381                 self.conv = (num/254000.0)*(self.resolution/den)
 382
 383                 # self.pyxconv is the conversion factor from the dvi units
 384                 # to (PostScript) points. It consists of
 385                 # - self.mag/1000.0:   magstep scaling
 386                 # - self.conv:         conversion from dvi units to pixels
 387                 # - 1/self.resolution: conversion from pixels to inch
 388                 # - 72               : conversion from inch to points
 389                 self.pyxconv = self.mag/1000.0*self.conv/self.resolution*72
 390
 391                 # scaling used for rules when VF chunks are interpreted
 392                 self.scale = 1
 393
 394                 comment = afile.read(afile.readuchar())
 395                 return
 396             else:
 397                 raise DVIError
 398
 399     def readpage(self, pageid=None, fontmap=None, singlecharmode=False):
 400         """ reads a page from the dvi file
 401
 402         This routine reads a page from the dvi file which is
 403         returned as a canvas. When there is no page left in the
 404         dvifile, None is returned and the file is closed properly."""
 405
 406         self.singlecharmode = singlecharmode
 407
 408         while True:
 409             self.filepos = self.file.tell()
 410             cmd = self.file.readuchar()
 411             if cmd == _DVI_NOP:
 412                 pass
 413             elif cmd == _DVI_BOP:
 414                 ispageid = [self.file.readuint32() for i in range(10)]
 415                 if pageid is not None and ispageid != pageid:
 416                     raise DVIError("invalid pageid")
 417                 if self.debug:
 418                     self.debugfile.write("%d: beginning of page %i\n" % (self.filepos, ispageid[0]))
 419                 self.file.readuint32()
 420                 break
 421             elif cmd == _DVI_POST:
 422                 self.file.close()
 423                 return None # nothing left
 424             else:
 425                 raise DVIError
 426
 427         self.actpage = canvas.canvas()
 428         self.actpage.markers = {}
 429         self.pos = [0, 0, 0, 0, 0, 0]
 430
 431         # tuple (hpos, vpos, codepoints) to be output, or None if no output is pending
 432         self.activetext = None
 433
 434         while True:
 435             afile = self.file
 436             self.filepos = afile.tell()
 437             try:
 438                 cmd = afile.readuchar()
 439             except struct.error:
 440                 # we most probably (if the dvi file is not corrupt) hit the end of a dvi chunk,
 441                 # so we have to continue with the rest of the dvi file
 442                 self._pop_dvistring(fontmap)
 443                 continue
 444             if cmd == _DVI_NOP:
 445                 pass
 446             if cmd >= _DVI_CHARMIN and cmd <= _DVI_CHARMAX:
 447                 self.putchar(cmd, True, 0, fontmap)
 448             elif cmd >= _DVI_SET1234 and cmd < _DVI_SET1234 + 4:
 449                 self.putchar(afile.readint(cmd - _DVI_SET1234 + 1), True, cmd-_DVI_SET1234+1, fontmap)
 450             elif cmd == _DVI_SETRULE:
 451                 self.putrule(afile.readint32()*self.scale, afile.readint32()*self.scale, True, fontmap)
 452             elif cmd >= _DVI_PUT1234 and cmd < _DVI_PUT1234 + 4:
 453                 self.putchar(afile.readint(cmd - _DVI_PUT1234 + 1), False, cmd-_DVI_SET1234+1, fontmap)
 454             elif cmd == _DVI_PUTRULE:
 455                 self.putrule(afile.readint32()*self.scale, afile.readint32()*self.scale, False, fontmap)
 456             elif cmd == _DVI_EOP:
 457                 self.flushtext(fontmap)
 458                 if self.debug:
 459                     self.debugfile.write("%d: eop\n \n" % self.filepos)
 460                 return self.actpage
 461             elif cmd == _DVI_PUSH:
 462                 self.stack.append(list(self.pos))
 463                 if self.debug:
 464                     self.debugfile.write("%s: push\n"
 465                                          "level %d:(h=%d,v=%d,w=%d,x=%d,y=%d,z=%d,hh=???,vv=???)\n" %
 466                                          ((self.filepos, len(self.stack)-1) + tuple(self.pos)))
 467             elif cmd == _DVI_POP:
 468                 self.flushtext(fontmap)
 469                 self.pos = self.stack.pop()
 470                 if self.debug:
 471                     self.debugfile.write("%s: pop\n"
 472                                          "level %d:(h=%d,v=%d,w=%d,x=%d,y=%d,z=%d,hh=???,vv=???)\n" %
 473                                          ((self.filepos, len(self.stack)) + tuple(self.pos)))
 474             elif cmd >= _DVI_RIGHT1234 and cmd < _DVI_RIGHT1234 + 4:
 475                 self.flushtext(fontmap)
 476                 dh = afile.readint(cmd - _DVI_RIGHT1234 + 1, 1) * self.scale
 477                 if self.debug:
 478                     self.debugfile.write("%d: right%d %d h:=%d%+d=%d, hh:=???\n" %
 479                                          (self.filepos,
 480                                           cmd - _DVI_RIGHT1234 + 1,
 481                                           dh,
 482                                           self.pos[_POS_H],
 483                                           dh,
 484                                           self.pos[_POS_H]+dh))
 485                 self.pos[_POS_H] += dh
 486             elif cmd == _DVI_W0:
 487                 self.flushtext(fontmap)
 488                 if self.debug:
 489                     self.debugfile.write("%d: w0 %d h:=%d%+d=%d, hh:=???\n" %
 490                                          (self.filepos,
 491                                           self.pos[_POS_W],
 492                                           self.pos[_POS_H],
 493                                           self.pos[_POS_W],
 494                                           self.pos[_POS_H]+self.pos[_POS_W]))
 495                 self.pos[_POS_H] += self.pos[_POS_W]
 496             elif cmd >= _DVI_W1234 and cmd < _DVI_W1234 + 4:
 497                 self.flushtext(fontmap)
 498                 self.pos[_POS_W] = afile.readint(cmd - _DVI_W1234 + 1, 1) * self.scale
 499                 if self.debug:
 500                     self.debugfile.write("%d: w%d %d h:=%d%+d=%d, hh:=???\n" %
 501                                          (self.filepos,
 502                                           cmd - _DVI_W1234 + 1,
 503                                           self.pos[_POS_W],
 504                                           self.pos[_POS_H],
 505                                           self.pos[_POS_W],
 506                                           self.pos[_POS_H]+self.pos[_POS_W]))
 507                 self.pos[_POS_H] += self.pos[_POS_W]
 508             elif cmd == _DVI_X0:
 509                 self.flushtext(fontmap)
 510                 if self.debug:
 511                     self.debugfile.write("%d: x0 %d h:=%d%+d=%d, hh:=???\n" %
 512                                          (self.filepos,
 513                                           self.pos[_POS_X],
 514                                           self.pos[_POS_H],
 515                                           self.pos[_POS_X],
 516                                           self.pos[_POS_H]+self.pos[_POS_X]))
 517                 self.pos[_POS_H] += self.pos[_POS_X]
 518             elif cmd >= _DVI_X1234 and cmd < _DVI_X1234 + 4:
 519                 self.flushtext(fontmap)
 520                 self.pos[_POS_X] = afile.readint(cmd - _DVI_X1234 + 1, 1) * self.scale
 521                 if self.debug:
 522                     self.debugfile.write("%d: x%d %d h:=%d%+d=%d, hh:=???\n" %
 523                                          (self.filepos,
 524                                           cmd - _DVI_X1234 + 1,
 525                                           self.pos[_POS_X],
 526                                           self.pos[_POS_H],
 527                                           self.pos[_POS_X],
 528                                           self.pos[_POS_H]+self.pos[_POS_X]))
 529                 self.pos[_POS_H] += self.pos[_POS_X]
 530             elif cmd >= _DVI_DOWN1234 and cmd < _DVI_DOWN1234 + 4:
 531                 self.flushtext(fontmap)
 532                 dv = afile.readint(cmd - _DVI_DOWN1234 + 1, 1) * self.scale
 533                 if self.debug:
 534                     self.debugfile.write("%d: down%d %d v:=%d%+d=%d, vv:=???\n" %
 535                                          (self.filepos,
 536                                           cmd - _DVI_DOWN1234 + 1,
 537                                           dv,
 538                                           self.pos[_POS_V],
 539                                           dv,
 540                                           self.pos[_POS_V]+dv))
 541                 self.pos[_POS_V] += dv
 542             elif cmd == _DVI_Y0:
 543                 self.flushtext(fontmap)
 544                 if self.debug:
 545                     self.debugfile.write("%d: y0 %d v:=%d%+d=%d, vv:=???\n" %
 546                                          (self.filepos,
 547                                           self.pos[_POS_Y],
 548                                           self.pos[_POS_V],
 549                                           self.pos[_POS_Y],
 550                                           self.pos[_POS_V]+self.pos[_POS_Y]))
 551                 self.pos[_POS_V] += self.pos[_POS_Y]
 552             elif cmd >= _DVI_Y1234 and cmd < _DVI_Y1234 + 4:
 553                 self.flushtext(fontmap)
 554                 self.pos[_POS_Y] = afile.readint(cmd - _DVI_Y1234 + 1, 1) * self.scale
 555                 if self.debug:
 556                     self.debugfile.write("%d: y%d %d v:=%d%+d=%d, vv:=???\n" %
 557                                          (self.filepos,
 558                                           cmd - _DVI_Y1234 + 1,
 559                                           self.pos[_POS_Y],
 560                                           self.pos[_POS_V],
 561                                           self.pos[_POS_Y],
 562                                           self.pos[_POS_V]+self.pos[_POS_Y]))
 563                 self.pos[_POS_V] += self.pos[_POS_Y]
 564             elif cmd == _DVI_Z0:
 565                 self.flushtext(fontmap)
 566                 if self.debug:
 567                     self.debugfile.write("%d: z0 %d v:=%d%+d=%d, vv:=???\n" %
 568                                          (self.filepos,
 569                                           self.pos[_POS_Z],
 570                                           self.pos[_POS_V],
 571                                           self.pos[_POS_Z],
 572                                           self.pos[_POS_V]+self.pos[_POS_Z]))
 573                 self.pos[_POS_V] += self.pos[_POS_Z]
 574             elif cmd >= _DVI_Z1234 and cmd < _DVI_Z1234 + 4:
 575                 self.flushtext(fontmap)
 576                 self.pos[_POS_Z] = afile.readint(cmd - _DVI_Z1234 + 1, 1) * self.scale
 577                 if self.debug:
 578                     self.debugfile.write("%d: z%d %d v:=%d%+d=%d, vv:=???\n" %
 579                                          (self.filepos,
 580                                           cmd - _DVI_Z1234 + 1,
 581                                           self.pos[_POS_Z],
 582                                           self.pos[_POS_V],
 583                                           self.pos[_POS_Z],
 584                                           self.pos[_POS_V]+self.pos[_POS_Z]))
 585                 self.pos[_POS_V] += self.pos[_POS_Z]
 586             elif cmd >= _DVI_FNTNUMMIN and cmd <= _DVI_FNTNUMMAX:
 587                 self.usefont(cmd - _DVI_FNTNUMMIN, 0, fontmap)
 588             elif cmd >= _DVI_FNT1234 and cmd < _DVI_FNT1234 + 4:
 589                 # note that according to the DVI docs, for four byte font numbers,
 590                 # the font number is signed. Don't ask why!
 591                 fntnum = afile.readint(cmd - _DVI_FNT1234 + 1, cmd == _DVI_FNT1234 + 3)
 592                 self.usefont(fntnum, cmd-_DVI_FNT1234+1, fontmap)
 593             elif cmd >= _DVI_SPECIAL1234 and cmd < _DVI_SPECIAL1234 + 4:
 594                 self.special(afile.read(afile.readint(cmd - _DVI_SPECIAL1234 + 1)).decode("ascii"), fontmap)
 595             elif cmd >= _DVI_FNTDEF1234 and cmd < _DVI_FNTDEF1234 + 4:
 596                 if cmd == _DVI_FNTDEF1234:
 597                     num = afile.readuchar()
 598                 elif cmd == _DVI_FNTDEF1234+1:
 599                     num = afile.readuint16()
 600                 elif cmd == _DVI_FNTDEF1234+2:
 601                     num = afile.readuint24()
 602                 elif cmd == _DVI_FNTDEF1234+3:
 603                     # Cool, here we have according to docu a signed int. Why?
 604                     num = afile.readint32()
 605                 self.definefont(cmd-_DVI_FNTDEF1234+1,
 606                                 num,
 607                                 afile.readint32(),
 608                                 afile.readint32(),
 609                                 afile.readint32(),
 610                                 afile.read(afile.readuchar()+afile.readuchar()).decode("ascii"))
 611             else:
 612                 raise DVIError