pyx/document.py

   1 #!/usr/bin/env python
   2 # -*- coding: ISO-8859-1 -*-
   3 #
   4 #
   5 # Copyright (C) 2005 Jörg Lehmann <joergl@users.sourceforge.net>
   6 # Copyright (C) 2005 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 cStringIO, warnings
  25 import bbox, pswriter, pdfwriter, trafo, style, unit
  26
  27
  28 class paperformat:
  29
  30     def __init__(self, width, height, name=None):
  31         self.width = width
  32         self.height = height
  33         self.name = name
  34
  35 paperformat.A4 = paperformat(210 * unit.t_mm, 297  * unit.t_mm, "A4")
  36 paperformat.A3 = paperformat(297 * unit.t_mm, 420  * unit.t_mm, "A3")
  37 paperformat.A2 = paperformat(420 * unit.t_mm, 594  * unit.t_mm, "A2")
  38 paperformat.A1 = paperformat(594 * unit.t_mm, 840  * unit.t_mm, "A1")
  39 paperformat.A0 = paperformat(840 * unit.t_mm, 1188 * unit.t_mm, "A0")
  40 paperformat.A0b = paperformat(910 * unit.t_mm, 1370 * unit.t_mm, None) # dedicated to our friends in Augsburg
  41 paperformat.Letter = paperformat(8.5 * unit.t_inch, 11 * unit.t_inch, "Letter")
  42 paperformat.Legal = paperformat(8.5 * unit.t_inch, 14 * unit.t_inch, "Legal")
  43
  44 def _paperformatfromstring(name):
  45     return getattr(paperformat, name.capitalize())
  46
  47
  48 class page:
  49
  50     def __init__(self, canvas, pagename=None, paperformat=None, rotated=0, centered=1, fittosize=0,
  51                  margin=1*unit.t_cm, bboxenlarge=1*unit.t_pt, bbox=None):
  52         self.canvas = canvas
  53         self.pagename = pagename
  54         # support for depricated string specification of paper formats
  55         try:
  56             paperformat + ""
  57         except:
  58             self.paperformat = paperformat
  59         else:
  60             self.paperformat = _paperformatfromstring(paperformat)
  61             warnings.warn("specification of paperformat by string is deprecated, use document.paperformat.%s instead" % paperformat.capitalize(), DeprecationWarning)
  62
  63         self.rotated = rotated
  64         self.centered = centered
  65         self.fittosize = fittosize
  66         self.margin = margin
  67         self.bboxenlarge = bboxenlarge
  68         self.pagebbox = bbox
  69
  70     def _process(self, processMethod, contentfile, writer, context, registry, bbox):
  71         assert not bbox
  72
  73         # check whether we expect a page trafo and use a temporary canvasfile to insert the
  74         # pagetrafo in front after the bbox was calculated
  75         expectpagetrafo = self.paperformat and (self.rotated or self.centered or self.fittosize)
  76         if expectpagetrafo:
  77             canvasfile = cStringIO.StringIO()
  78         else:
  79             canvasfile = contentfile
  80
  81         getattr(style.linewidth.normal, processMethod)(canvasfile, writer, context, registry, bbox)
  82         getattr(self.canvas, processMethod)(canvasfile, writer, context, registry, bbox)
  83
  84         # usually its the bbox of the canvas enlarged by self.bboxenlarge, but
  85         # it might be a different bbox as specified in the page constructor
  86         if self.pagebbox:
  87             bbox.set(self.pagebbox)
  88         elif bbox:
  89             bbox.enlarge(self.bboxenlarge)
  90
  91         if expectpagetrafo:
  92
  93             if bbox:
  94                 # calculate the pagetrafo
  95                 paperwidth, paperheight = self.paperformat.width, self.paperformat.height
  96
  97                 # center (optionally rotated) output on page
  98                 if self.rotated:
  99                     pagetrafo = trafo.rotate(90).translated(paperwidth, 0)
 100                     if self.centered or self.fittosize:
 101                         if not self.fittosize and (bbox.height() > paperwidth or bbox.width() > paperheight):
 102                             warnings.warn("content exceeds the papersize")
 103                         pagetrafo = pagetrafo.translated(-0.5*(paperwidth - bbox.height()) + bbox.bottom(),
 104                                                           0.5*(paperheight - bbox.width()) - bbox.left())
 105                 else:
 106                     if not self.fittosize and (bbox.width() > paperwidth or bbox.height() > paperheight):
 107                         warnings.warn("content exceeds the papersize")
 108                     pagetrafo = trafo.translate(0.5*(paperwidth - bbox.width())  - bbox.left(),
 109                                                 0.5*(paperheight - bbox.height()) - bbox.bottom())
 110
 111                 if self.fittosize:
 112
 113                     if 2*self.margin > paperwidth or 2*self.margin > paperheight:
 114                         raise ValueError("Margins too broad for selected paperformat. Aborting.")
 115
 116                     paperwidth -= 2 * self.margin
 117                     paperheight -= 2 * self.margin
 118
 119                     # scale output to pagesize - margins
 120                     if self.rotated:
 121                         sfactor = min(unit.topt(paperheight)/bbox.width_pt(), unit.topt(paperwidth)/bbox.height_pt())
 122                     else:
 123                         sfactor = min(unit.topt(paperwidth)/bbox.width_pt(), unit.topt(paperheight)/bbox.height_pt())
 124
 125                     pagetrafo = pagetrafo.scaled(sfactor, sfactor, self.margin + 0.5*paperwidth, self.margin + 0.5*paperheight)
 126
 127                 # apply the pagetrafo and write it to the contentfile
 128                 bbox.transform(pagetrafo)
 129                 pagetrafofile = cStringIO.StringIO()
 130                 # context, bbox, registry are just passed as stubs (the trafo should not touch them)
 131                 getattr(pagetrafo, processMethod)(pagetrafofile, writer, context, registry, bbox)
 132                 contentfile.write(pagetrafofile.getvalue())
 133                 pagetrafofile.close()
 134
 135             contentfile.write(canvasfile.getvalue())
 136             canvasfile.close()
 137
 138     def processPS(self, *args):
 139         self._process("processPS", *args)
 140
 141     def processPDF(self, *args):
 142         self._process("processPDF", *args)
 143
 144
 145 class document:
 146
 147     """holds a collection of page instances which are output as pages of a document"""
 148
 149     def __init__(self, pages=[]):
 150         self.pages = pages
 151
 152     def append(self, page):
 153         self.pages.append(page)
 154
 155     def writeEPSfile(self, filename, *args, **kwargs):
 156         pswriter.epswriter(self, filename, *args, **kwargs)
 157
 158     def writePSfile(self, filename, *args, **kwargs):
 159         pswriter.pswriter(self, filename, *args, **kwargs)
 160
 161     def writePDFfile(self, filename, *args, **kwargs):
 162         pdfwriter.PDFwriter(self, filename, *args, **kwargs)
 163
 164     def writetofile(self, filename, *args, **kwargs):
 165         if filename.endswith(".eps"):
 166             self.writeEPSfile(filename, *args, **kwargs)
 167         elif filename.endswith(".ps"):
 168             self.writePSfile(filename, *args, **kwargs)
 169         elif filename.endswith(".pdf"):
 170             self.writePDFfile(filename, *args, **kwargs)
 171         else:
 172             raise ValueError("unknown file extension")