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 warnings
  25 import pswriter, pdfwriter, trafo, 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=0, 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 processPS(self, file, writer, context, registry, bbox):
  71         self.canvas.processPS(file, writer, context, registry, bbox)
  72         # usually its the bbox of the canvas enlarged by self.bboxenlarge, but
  73         # it might be a different bbox as specified in the page constructor
  74         if self.pagebbox:
  75             # we have to modify the bbox in place
  76             # XXX maybe there should be a bbox.set/replace routine which accepts another bbox as argument
  77             bbox.llx_pt = self.pagebbox.llx_pt
  78             bbox.lly_pt = self.pagebbox.lly_pt
  79             bbox.urx_pt = self.pagebbox.urx_pt
  80             bbox.ury_pt = self.pagebbox.ury_pt
  81         elif bbox:
  82             bbox.enlarge(self.bboxenlarge)
  83
  84     def pagetrafo(self, bbox):
  85         """ calculate a trafo which rotates and fits a canvas on the page
  86
  87         The canvas extents are described by bbox.
  88         """
  89         # XXX should we provide a method for bbox != empty (or use __zero__)
  90         if bbox.llx_pt is not None and self.paperformat and (self.rotated or self.centered or self.fittosize):
  91             paperwidth, paperheight = self.paperformat.width, self.paperformat.height
  92
  93             # center (optionally rotated) output on page
  94             if self.rotated:
  95                 atrafo = trafo.rotate(90).translated(paperwidth, 0)
  96                 if self.centered or self.fittosize:
  97                     if not self.fittosize and (bbox.height() > paperwidth or bbox.width() > paperheight):
  98                         warnings.warn("content exceeds the papersize")
  99                     atrafo = atrafo.translated(-0.5*(paperwidth - bbox.height()) + bbox.bottom(),
 100                                                0.5*(paperheight - bbox.width()) - bbox.left())
 101             else:
 102                 if self.centered or self.fittosize:
 103                     if not self.fittosize and (bbox.width() > paperwidth or bbox.height() > paperheight):
 104                         warnings.warn("content exceeds the papersize")
 105                     atrafo = trafo.translate(0.5*(paperwidth - bbox.width())  - bbox.left(),
 106                                              0.5*(paperheight - bbox.height()) - bbox.bottom())
 107                 else:
 108                     return None # no page transformation needed
 109
 110             if self.fittosize:
 111
 112                 if 2*self.margin > paperwidth or 2*self.margin > paperheight:
 113                     raise ValueError("Margins too broad for selected paperformat. Aborting.")
 114
 115                 paperwidth -= 2 * self.margin
 116                 paperheight -= 2 * self.margin
 117
 118                 # scale output to pagesize - margins
 119                 if self.rotated:
 120                     sfactor = min(unit.topt(paperheight)/bbox.width_pt(), unit.topt(paperwidth)/bbox.height_pt())
 121                 else:
 122                     sfactor = min(unit.topt(paperwidth)/bbox.width_pt(), unit.topt(paperheight)/bbox.height_pt())
 123
 124                 atrafo = atrafo.scaled(sfactor, sfactor, self.margin + 0.5*paperwidth, self.margin + 0.5*paperheight)
 125
 126             return atrafo
 127
 128         return None # no page transformation needed
 129
 130
 131 class document:
 132
 133     """holds a collection of page instances which are output as pages of a document"""
 134
 135     def __init__(self, pages=[]):
 136         self.pages = pages
 137
 138     def append(self, page):
 139         self.pages.append(page)
 140
 141     def writeEPSfile(self, filename, *args, **kwargs):
 142         pswriter.epswriter(self, filename, *args, **kwargs)
 143
 144     def writePSfile(self, filename, *args, **kwargs):
 145         pswriter.pswriter(self, filename, *args, **kwargs)
 146
 147     def writePDFfile(self, filename, *args, **kwargs):
 148         pdfwriter.PDFwriter(self, filename, *args, **kwargs)
 149
 150     def writetofile(self, filename, *args, **kwargs):
 151         if filename.endswith(".eps"):
 152             self.writeEPSfile(filename, *args, **kwargs)
 153         elif filename.endswith(".ps"):
 154             self.writePSfile(filename, *args, **kwargs)
 155         elif filename.endswith(".pdf"):
 156             self.writePDFfile(filename, *args, **kwargs)
 157         else:
 158             raise ValueError("unknown file extension")