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# -*- coding: iso-8859-1 -*-
A PDF matplotlib backend (not yet complete)
Author: Jouni K Seppänen <jks@iki.fi>
from __future__ import division

import md5
import os
import re
import sys
import time
import zlib

from cStringIO import StringIO
from datetime import datetime
from math import ceil, cos, floor, pi, sin

from matplotlib import __version__, rcParams, agg
from matplotlib._pylab_helpers import Gcf
from matplotlib.backend_bases import RendererBase, GraphicsContextBase,\
     FigureManagerBase, FigureCanvasBase
from matplotlib.cbook import Bunch, enumerate, is_string_like
from matplotlib.figure import Figure
from matplotlib.font_manager import fontManager
from matplotlib.ft2font import FT2Font, FIXED_WIDTH, ITALIC, LOAD_NO_SCALE
from matplotlib.mathtext import math_parse_s_pdf
from matplotlib.numerix import Float32, UInt8, fromstring, arange, infinity, isnan, asarray
from matplotlib.transforms import Bbox

# Overview
# The low-level knowledge about pdf syntax lies mainly in the pdfRepr
# function and the classes Reference, Name, Operator, and Stream.  The
# PdfFile class knows about the overall structure of pdf documents.
# It provides a "write" method for writing arbitrary strings in the
# file, and an "output" method that passes objects through the pdfRepr
# function before writing them in the file.  The output method is
# called by the RendererPdf class, which contains the various draw_foo
# methods.  RendererPdf contains a GraphicsContextPdf instance, and
# each draw_foo calls self.check_gc before outputting commands.  This
# method checks whether the pdf graphics state needs to be modified
# and outputs the necessary commands.  GraphicsContextPdf represents
# the graphics state, and its "delta" method returns the commands that
# modify the state.
# Some tricky points: 
# 1. The clip rectangle (which could in pdf be an arbitrary path, not
# necessarily a rectangle) can only be widened by popping from the
# state stack.  Thus the state must be pushed onto the stack before
# narrowing the rectangle.  This is taken care of by
# GraphicsContextPdf.
# 2. Sometimes it is necessary to refer to something (e.g. font,
# image, or extended graphics state, which contains the alpha value)
# in the page stream by a name that needs to be defined outside the
# stream.  PdfFile provides the methods fontName, imageObject, and
# alphaState for this purpose.  The implementations of these methods
# should perhaps be generalized.

# TODOs:
# * the alpha channel of images
# * image compression could be improved (PDF supports png-like compression) 
# * encoding of fonts, including mathtext fonts and unicode support
# * Type 1 and Base-14 font support (i.e., "pdf.use_afm") 
# * TTF support has lots of small TODOs, e.g. how do you know if a font  
#   is serif/sans-serif, or symbolic/non-symbolic? 
# * draw_markers, draw_line_collection, etc. 
# * use_tex 

def fill(strings, linelen=75):
    """Make one string from sequence of strings, with whitespace
    in between. The whitespace is chosen to form lines of at most
    linelen characters, if possible."""

    s, strings = [strings[0]], strings[1:]
    while strings:
      if len(s[-1]) + len(strings[0]) < linelen:
          s[-1] += ' ' + strings[0]
      strings = strings[1:]
    return '\n'.join(s)

def pdfRepr(obj):
    """Map Python objects to PDF syntax."""

    # Some objects defined later have their own pdfRepr method.
    if 'pdfRepr' in dir(obj):
      return obj.pdfRepr()

    # Floats. PDF does not have exponential notation (1.0e-10) so we
    # need to use %f with some precision.  Perhaps the precision
    # should adapt to the magnitude of the number?
    elif isinstance(obj, float):
      if isnan(obj) or obj in (-infinity, infinity):
          raise ValueError, "Can only output finite numbers in PDF"
      r = "%.10f" % obj
      return r.rstrip('0').rstrip('.')

    # Integers are written as such.
    elif isinstance(obj, (int, long)):
      return "%d" % obj

    # Strings are written in parentheses, with backslashes and parens
    # escaped. Actually balanced parens are allowed, but it is
    # simpler to escape them all. TODO: cut long strings into lines;
    # I believe there is some maximum line length in PDF.
    elif is_string_like(obj):
      return '(' + re.sub(r'([\\()])', r'\\\1', obj) + ')'

    # Dictionaries. The keys must be PDF names, so if we find strings
    # there, we make Name objects from them. The values may be
    # anything, so the caller must ensure that PDF names are
    # represented as Name objects.
    elif isinstance(obj, dict):
      r = ["<<"]
      r.extend(["%s %s" % (Name(key).pdfRepr(),
              for key, val in obj.items()])
      return fill(r)

    # Lists.
    elif isinstance(obj, (list, tuple)):
      r = ["["]
      r.extend([pdfRepr(val) for val in obj])
      return fill(r)

    # Booleans.
    elif isinstance(obj, bool):
      return ['false', 'true'][obj]

    # The null keyword.
    elif obj is None:
      return 'null'

    # A date.
    elif isinstance(obj, datetime):
      r = obj.strftime('D:%Y%m%d%H%M%S')
      if time.daylight: z = time.altzone
      else: z = time.timezone
      if z == 0: r += 'Z'
      elif z < 0: r += "+%02d'%02d'" % ((-z)//3600, (-z)%3600)
      else: r += "-%02d'%02d'" % (z//3600, z%3600)
      return pdfRepr(r)

      raise TypeError, \
          "Don't know a PDF representation for %s objects." \
          % type(obj)

00157 class Reference:
    """PDF reference object.
    Use PdfFile.reserveObject() to create References.

    def __init__(self, id):
      self.id = id

    def __repr__(self):
      return "<Reference %d>" % self.id

    def pdfRepr(self):
      return "%d 0 R" % self.id

    def write(self, contents, file):
      write = file.write
      write("%d 0 obj\n" % self.id)

00177 class Name:
    """PDF name object."""

    def __init__(self, name):
      if isinstance(name, Name):
          self.name = name.name
          self.name = re.sub(r'[^!-~]', Name.hexify, name)

    def __repr__(self):
      return "<Name %s>" % self.name

    def hexify(match):
      return '#%02x' % ord(match.group())
    hexify = staticmethod(hexify)

    def pdfRepr(self):
      return '/' + self.name

00196 class Operator:
    """PDF operator object."""

    def __init__(self, op):
      self.op = op

    def __repr__(self):
      return '<Operator %s>' % self.op

    def pdfRepr(self):
      return self.op

# PDF operators (not an exhaustive list)
_pdfops = dict(close_fill_stroke='b', fill_stroke='B', fill='f',
             closepath='h', close_stroke='s', stroke='S', endpath='n',
             begin_text='BT', end_text='ET',
             curveto='c', rectangle='re', lineto='l', moveto='m',
             setgray_stroke='G', setgray_nonstroke='g',
             setrgb_stroke='RG', setrgb_nonstroke='rg',
             setcolorspace_stroke='CS', setcolorspace_nonstroke='cs',
             setcolor_stroke='SCN', setcolor_nonstroke='scn',
             setdash='d', setlinejoin='j', setlinecap='J', setgstate='gs',
             gsave='q', grestore='Q',
             textpos='Td', selectfont='Tf', textmatrix='Tm',
             show='Tj', showkern='TJ',
             setlinewidth='w', clip='W')

Op = Bunch(**dict([(name, Operator(value)) 
               for name, value in _pdfops.items()]))

00228 class Stream:
    """PDF stream object.

    This has no pdfRepr method. Instead, call begin(), then output the
    contents of the stream by calling write(), and finally call end().

00235     def __init__(self, id, len, file, extra=None):
      """id: object id of stream; len: an unused Reference object for the
      length of the stream, or None (to use a memory buffer); file:
      a PdfFile; extra: a dictionary of extra key-value pairs to
      include in the stream header """
      self.id = id            # object id
      self.len = len          # id of length object
      self.pdfFile = file
      self.file = file.fh     # file to which the stream is written
      self.compressobj = None # compression object
      if extra is None: self.extra = dict()
      else: self.extra = extra

      if rcParams['pdf.compression']:
          self.compressobj = zlib.compressobj(rcParams['pdf.compression'])
      if self.len is None:
          self.file = StringIO()
          self.pos = self.file.tell()

    def _writeHeader(self):
      write = self.file.write
      write("%d 0 obj\n" % self.id)
      dict = self.extra
      dict['Length'] = self.len
      if rcParams['pdf.compression']:
          dict['Filter'] = Name('FlateDecode')


00268     def end(self):
      """Finalize stream."""

      if self.len is None:
          contents = self.file.getvalue()
          self.len = len(contents)
          self.file = self.pdfFile.fh
          length = self.file.tell() - self.pos
          self.pdfFile.writeObject(self.len, length)

00284     def write(self, data):
      """Write some data on the stream."""

      if self.compressobj is None:
          compressed = self.compressobj.compress(data)

00293     def _flush(self):
      """Flush the compression object."""

      if self.compressobj is not None:
          compressed = self.compressobj.flush()
          self.compressobj = None

00301 class PdfFile:
    """PDF file with one page."""

    def __init__(self, width, height, dpi, filename):
      self.nextObject = 1     # next free object id
      self.xrefTable = [ [0, 65535, 'the zero object'] ]
      self.dpi = dpi
      fh = file(filename, 'wb')
      self.fh = fh
      self.currentstream = None # stream object to write to, if any
      fh.write("%PDF-1.4\n")    # 1.4 is the first version to have alpha
      # Output some eight-bit chars as a comment so various utilities
      # recognize the file as binary by looking at the first few
      # lines (see note in section 3.4.1 of the PDF reference).
      fh.write("%\254\334 \253\272\n")

      self.rootObject = self.reserveObject('root')
      self.infoObject = self.reserveObject('info')
      pagesObject = self.reserveObject('pages')
      thePageObject = self.reserveObject('page 0')
      contentObject = self.reserveObject('contents of page 0')
      self.fontObject = self.reserveObject('fonts')
      self.alphaStateObject = self.reserveObject('extended graphics states')
      self.hatchObject = self.reserveObject('tiling patterns')
      self.XObjectObject = self.reserveObject('external objects')
      resourceObject = self.reserveObject('resources')

      root = { 'Type': Name('Catalog'),
             'Pages': pagesObject }
      self.writeObject(self.rootObject, root)

      info = { 'Creator': 'matplotlib ' + __version__ \
             + ', http://matplotlib.sf.net',
             'Producer': 'matplotlib pdf backend',
             'CreationDate': datetime.today() }

      # Possible TODO: Title, Author, Subject, Keywords
      self.writeObject(self.infoObject, info)

      pages = { 'Type': Name('Pages'),
              'Kids': [ thePageObject ],
              'Count': 1 }
      self.writeObject(pagesObject, pages)

      thePage = { 'Type': Name('Page'),
                'Parent': pagesObject,
                'Resources': resourceObject,
                'MediaBox': [ 0, 0, 72*width, 72*height ],
                'Contents': contentObject }
      self.writeObject(thePageObject, thePage)

      # self.fontNames maps filenames to internal font names
      self.fontNames = {}
      self.nextFont = 1 # next free internal font name

      self.alphaStates = {}   # maps alpha values to graphics state objects
      self.nextAlphaState = 1
      self.hatchPatterns = {}
      self.nextHatch = 1

      self.images = {}
      self.nextImage = 1

      self.markers = {}
      self.nextMarker = 1

      # The PDF spec recommends to include every procset
      procsets = [ Name(x)
                 for x in "PDF Text ImageB ImageC ImageI".split() ]

      # Write resource dictionary.
      # Possibly TODO: more general ExtGState (graphics state dictionaries)
      #                ColorSpace Pattern Shading Properties
      resources = { 'Font': self.fontObject,
                  'XObject': self.XObjectObject,
                  'ExtGState': self.alphaStateObject,
                  'Pattern': self.hatchObject,
                  'ProcSet': procsets }
      self.writeObject(resourceObject, resources)

      # Start the content stream of the page
                   self.reserveObject('length of content stream'))

    def close(self):
      # End the content stream and write out the various deferred
      # objects
                   dict([(val[0], val[1])
                         for val in self.alphaStates.values()]))
      xobjects = dict(self.images.values())
      xobjects.update([(name, value[0]) for (name, value) in self.markers.items()])
      self.writeObject(self.XObjectObject, xobjects)

    def write(self, data):
      if self.currentstream is None:

    def output(self, *data):
      self.write(fill(map(pdfRepr, data)))

    def beginStream(self, id, len, extra=None):
      assert self.currentstream is None
      self.currentstream = Stream(id, len, self, extra)

    def endStream(self):
      self.currentstream = None

    # These fonts do not need to be embedded; every PDF viewing
    # application is required to have them.
    base14 = [ 'Times-Roman', 'Times-Bold', 'Times-Italic',
             'Times-BoldItalic', 'Symbol', 'ZapfDingbats' ] + \
           [ prefix + postfix
             for prefix in 'Helvetica', 'Courier'
             for postfix in '', '-Bold', '-Oblique', '-BoldOblique' ]

    def fontName(self, fontprop):
      if is_string_like(fontprop):
          filename = fontprop
          filename = fontManager.findfont(fontprop)
      Fx = self.fontNames.get(filename, None)
      if Fx is None:
          Fx = Name('F%d' % self.nextFont)
          self.fontNames[filename] = Fx
          self.nextFont += 1
      return Fx

    def writeFonts(self):
      fonts = {}
      for filename, Fx in self.fontNames.items():
          # TODO: The following test is wrong, since findfont really
          # returns a file name. Think about how to allow users to
          # specify the base14 fonts (does fontManager know anything
          # about them?).
          if filename in self.base14:
            fontdict = { 'Subtype': Name('Type1'),
                       'BaseFont': Name(filename) }
            # etc...
            fontdictObject = self.embedTTF(filename)
          fonts[Fx] = fontdictObject
          #print >>sys.stderr, filename

      self.writeObject(self.fontObject, fonts)

00459     def embedTTF(self, filename):
      """Embed the TTF font from the named file into the document."""

      font = FT2Font(filename)

      def cvt(length, upe=font.units_per_EM, nearest=True):
          "Convert font coordinates to PDF glyph coordinates"
          value = length / upe * 1000
          if nearest: return round(value)
          # Perhaps best to round away from zero for bounding
          # boxes and the like
          if value < 0: return floor(value)
          else: return ceil(value)

      # You are lost in a maze of TrueType tables, all different...
      ps_name = Name(font.get_sfnt()[(1,0,0,6)])
      pclt = font.get_sfnt_table('pclt') \
          or { 'capHeight': 0, 'xHeight': 0 }
      post = font.get_sfnt_table('post') \
          or { 'italicAngle': (0,0) }
      ff = font.face_flags
      sf = font.style_flags
      charmap = font.get_charmap()
      chars = sorted(charmap.keys())
      firstchar, lastchar = chars[0], chars[-1]

      # Get widths
      widths = [ cvt(font.load_char(i, flags=LOAD_NO_SCALE).horiAdvance)
               for i in range(firstchar, lastchar+1) ]
      # Remove redundant widths from end and beginning; doing the
      # end first helps reduce LastChar, which apparently needs to
      # be less than 256 or acroread complains.
      missingwidth = widths[-1]
      while len(widths)>1 and widths[-1] == missingwidth:
          lastchar -= 1
      while len(widths)>1 and widths[0] == missingwidth:
          firstchar += 1

      widthsObject = self.reserveObject('font widths')
      fontdescObject = self.reserveObject('font descriptor')
      fontdict = { 'Type': Name('Font'),
                 'Subtype': Name('TrueType'),
                 'Encoding': Name('WinAnsiEncoding'), # ???
                 'BaseFont': ps_name,
                 'FirstChar': firstchar,
                 'LastChar': lastchar,
                 'Widths': widthsObject,
                 'FontDescriptor': fontdescObject }
      # TODO: Encoding?

      flags = 0
      symbolic = False #ps_name.name in ('Cmsy10', 'Cmmi10', 'Cmex10')
      if ff & FIXED_WIDTH: flags |= 1 << 0
      if 0: flags |= 1 << 1 # TODO: serif
      if symbolic: flags |= 1 << 2
      else: flags |= 1 << 5
      if sf & ITALIC: flags |= 1 << 6
      if 0: flags |= 1 << 16 # TODO: all caps
      if 0: flags |= 1 << 17 # TODO: small caps
      if 0: flags |= 1 << 18 # TODO: force bold

      descriptor = {
          'Type': Name('FontDescriptor'),
          'FontName': ps_name,
          'Flags': flags,
          'FontBBox': [ cvt(x, nearest=False) for x in font.bbox ],
          'Ascent': cvt(font.ascender, nearest=False),
          'Descent': cvt(font.descender, nearest=False),
          'CapHeight': cvt(pclt['capHeight'], nearest=False),
          'XHeight': cvt(pclt['xHeight']),
          'ItalicAngle': post['italicAngle'][1], # ???
          'FontFile2': self.reserveObject('font file'),
          'MaxWidth': max(widths+[missingwidth]),
          'MissingWidth': missingwidth,
          'StemV': 0 # ???

      # Other FontDescriptor keys include:
      # /FontFamily /Times (optional)
      # /FontStretch /Normal (optional)
      # /FontFile (stream for type 1 font)
      # /CharSet (used when subsetting type1 fonts)

      # Make an Identity-H encoded CID font for CM fonts? (Doesn't quite work)
      if False:
          del fontdict['Widths'], fontdict['FontDescriptor'], \
            fontdict['LastChar'], fontdict['FirstChar']

          fontdict['Subtype'] = Name('Type0')
          fontdict['Encoding'] = Name('Identity-H')
          fontdict2Object = self.reserveObject('descendant font')
          fontdict['DescendantFonts'] = [ fontdict2Object ]
          # TODO: fontdict['ToUnicode']
          fontdict2 = { 'Type': Name('Font'),
                    'Subtype': Name('CIDFontType2'),
                    'BaseFont': ps_name,
                    'W': widthsObject,
                    'DW': missingwidth,
                    'CIDSystemInfo': { 'Registry': 'Adobe', 
                                   'Ordering': 'Identity', 
                                   'Supplement': 0 },
                    'FontDescriptor': fontdescObject }
          self.writeObject(fontdict2Object, fontdict2)

          widths = [ firstchar, widths ]

      fontdictObject = self.reserveObject('font dictionary')
      length1Object = self.reserveObject('decoded length of a font')
      self.writeObject(fontdictObject, fontdict)
      self.writeObject(widthsObject, widths)
      self.writeObject(fontdescObject, descriptor)
                   self.reserveObject('length of font stream'),
                   {'Length1': length1Object})
      fontfile = open(filename, 'rb')
      length1 = 0
      while True:
          data = fontfile.read(4096)
          if not data: break
          length1 += len(data)
      self.writeObject(length1Object, length1)

      return fontdictObject

00587     def alphaState(self, alpha):
      """Return name of an ExtGState that sets alpha to the given value"""

      state = self.alphaStates.get(alpha, None)
      if state is not None:
          return state[0]

      name = Name('A%d' % self.nextAlphaState)
      self.nextAlphaState += 1
      self.alphaStates[alpha] = \
          (name, { 'Type': Name('ExtGState'),
                 'CA': alpha, 'ca': alpha })
      return name

    def hatchPattern(self, lst):
      pattern = self.hatchPatterns.get(lst, None)
      if pattern is not None:
          return pattern[0]

      name = Name('H%d' % self.nextHatch)
      self.nextHatch += 1
      self.hatchPatterns[lst] = name
      return name

    def writeHatches(self):
      hatchDict = dict()
      sidelen = 144.0
      density = 24.0
      for lst, name in self.hatchPatterns.items():
          ob = self.reserveObject('hatch pattern')
          hatchDict[name] = ob
          res = { 'Procsets': 
                [ Name(x) for x in "PDF Text ImageB ImageC ImageI".split() ] }
            ob.id, None, 
            { 'Type': Name('Pattern'),
              'PatternType': 1, 'PaintType': 1, 'TilingType': 1,
              'BBox': [0, 0, sidelen, sidelen],
              'XStep': sidelen, 'YStep': sidelen,
              'Resources': res })

          # lst is a tuple of stroke color, fill color, 
          # number of - lines, number of / lines, 
          # number of | lines, number of \ lines
          rgb = lst[0]
          self.output(rgb[0], rgb[1], rgb[2], Op.setrgb_stroke)
          if lst[1] is not None:
            rgb = lst[1]
            self.output(rgb[0], rgb[1], rgb[2], Op.setrgb_nonstroke,
                      0, 0, sidelen, sidelen, Op.rectangle,
          if lst[2]:          # -
            for j in arange(0.0, sidelen, density/lst[2]):
                self.output(0, j, Op.moveto,
                        sidelen, j, Op.lineto)
          if lst[3]:          # /
            for j in arange(0.0, sidelen, density/lst[3]):
                self.output(0, j, Op.moveto,
                        sidelen-j, sidelen, Op.lineto,
                        sidelen-j, 0, Op.moveto,
                        sidelen, j, Op.lineto)
          if lst[4]:          # |
            for j in arange(0.0, sidelen, density/lst[4]):
                self.output(j, 0, Op.moveto,
                        j, sidelen, Op.lineto)
          if lst[5]:          # \
            for j in arange(sidelen, 0.0, -density/lst[5]):
                self.output(sidelen, j, Op.moveto,
                        j, sidelen, Op.lineto,
                        j, 0, Op.moveto,
                        0, j, Op.lineto)

      self.writeObject(self.hatchObject, hatchDict)

00663     def imageObject(self, image):
      """Return name of an image XObject representing the given image."""

      pair = self.images.get(image, None)
      if pair is not None:
          return pair[0]

      name = Name('I%d' % self.nextImage)
      ob = self.reserveObject('image %d' % self.nextImage)
      self.nextImage += 1
      self.images[image] = (name, ob)
      return name

    ## These two from backend_ps.py
    ## TODO: alpha (SMask, p. 518 of pdf spec)

00679     def _rgb(self, im):
        h,w,s = im.as_rgba_str()

        rgba = fromstring(s, UInt8)
        rgba.shape = (h, w, 4)
        rgb = rgba[:,:,:3]
        return h, w, rgb.tostring()

    def _gray(self, im, rc=0.3, gc=0.59, bc=0.11):
        rgbat = im.as_rgba_str()
        rgba = fromstring(rgbat[2], UInt8)
        rgba.shape = (rgbat[0], rgbat[1], 4)
        rgba_f = rgba.astype(Float32)
        r = rgba_f[:,:,0]
        g = rgba_f[:,:,1]
        b = rgba_f[:,:,2]
        gray = (r*rc + g*gc + b*bc).astype(UInt8)
        return rgbat[0], rgbat[1], gray.tostring()

    def writeImages(self):
      for img, pair in self.images.items():
          if img.is_grayscale:
            height, width, data = self._gray(img)
            colorspace = Name('DeviceGray')
            height, width, data = self._rgb(img)
            colorspace = Name('DeviceRGB')

            self.reserveObject('length of image stream'), 
            {'Type': Name('XObject'), 'Subtype': Name('Image'),
             'Width': width, 'Height': height,
             'ColorSpace': colorspace, 'BitsPerComponent': 8 })
          self.currentstream.write(data) # TODO: predictors (i.e., output png)


00719     def markerObject(self, path, fillp, lw):
      """Return name of a marker XObject representing the given path."""

      name = Name('M%d' % self.nextMarker)
      ob = self.reserveObject('marker %d' % self.nextMarker)
      self.nextMarker += 1
      self.markers[name] = (ob, path, fillp, lw)
      return name

    def writeMarkers(self):
      for name, tuple in self.markers.items():
          object, path, fillp, lw = tuple
            object.id, None, 
            {'Type': Name('XObject'), 'Subtype': Name('Form'),
             'BBox': self.pathBbox(path, lw) })
          self.writePath(path, fillp)

    def pathBbox(path, lw):
      x, y = [], []
      while True:
          code, xp, yp = path.vertex()
          if code & agg.path_cmd_mask in \
                (agg.path_cmd_move_to, agg.path_cmd_line_to):
          elif code == agg.path_cmd_stop:
      return min(x)-lw, min(y)-lw, max(x)+lw, max(y)+lw
    pathBbox = staticmethod(pathBbox)

    def writePath(self, path, fillp):
      while True:
          code, xp, yp = path.vertex()
          code = code & agg.path_cmd_mask
          if code == agg.path_cmd_stop:
            elif code == agg.path_cmd_move_to:
            self.output(xp, yp, Op.moveto)
            elif code == agg.path_cmd_line_to:
            self.output(xp, yp, Op.lineto)
            elif code == agg.path_cmd_curve3:
            elif code == agg.path_cmd_curve4:
            elif code == agg.path_cmd_end_poly:
                print >>sys.stderr, "writePath", code, xp, yp
      if fillp:

00776     def reserveObject(self, name=''):
      """Reserve an ID for an indirect object.
      The name is used for debugging in case we forget to print out
      the object with writeObject.

      id = self.nextObject
      self.nextObject += 1
      self.xrefTable.append([None, 0, name])
      return Reference(id)

    def recordXref(self, id):
      self.xrefTable[id][0] = self.fh.tell()

    def writeObject(self, object, contents):
      object.write(contents, self)

00794     def writeXref(self):
      """Write out the xref table."""

      self.startxref = self.fh.tell()
      self.write("xref\n0 %d\n" % self.nextObject)
      i = 0
      borken = False
      for offset, generation, name in self.xrefTable:
          if offset is None:
            print >>sys.stderr, \
                'No offset for object %d (%s)' % (i, name)
            borken = True
            self.write("%010d %05d n \n" % (offset, generation))
          i += 1
      if borken:
          raise AssertionError, 'Indirect object does not exist'

00812     def writeTrailer(self):
      """Write out the PDF trailer."""

            {'Size': self.nextObject,
             'Root': self.rootObject,
             'Info': self.infoObject }))
      # Could add 'ID'
      self.write("\nstartxref\n%d\n%%%%EOF\n" % self.startxref)

class RendererPdf(RendererBase):

    def __init__(self, file):
      self.file = file
      self.gc = self.new_gc()
      self.fonts = {}
      self.dpi_factor = 72.0/file.dpi

    def points_to_pixels(self, points):
      return points / self.dpi_factor

    def finalize(self):

    def check_gc(self, gc, fillcolor=None):
      orig_fill = gc._fillcolor
      gc._fillcolor = fillcolor

      delta = self.gc.delta(gc)
      if delta: self.file.output(*delta)

      # Restore gc to avoid unwanted side effects
      gc._fillcolor = orig_fill

    def draw_arc(self, gcEdge, rgbFace, x, y, width, height, 
             angle1, angle2, rotation):
        Draw an arc using GraphicsContext instance gcEdge, centered at x,y,
        with width and height and angles from 0.0 to 360.0
        0 degrees is at 3-o'clock, rotated by `rotation` degrees
        positive angles are anti-clockwise

        If the color rgbFace is not None, fill the arc with it.
      # source: agg_bezier_arc.cpp in agg23

      x *= self.dpi_factor
      y *= self.dpi_factor
      width *= self.dpi_factor
      height *= self.dpi_factor
      def arc_to_bezier(cx, cy, rx, ry, angle1, sweep):
          halfsweep = sweep / 2.0
          x0, y0 = cos(halfsweep), sin(halfsweep)
          tx = (1.0 - x0) * 4.0/3.0;
          ty = y0 - tx * x0 / y0;
          px =  x0, x0+tx, x0+tx, x0
          py = -y0,   -ty,    ty, y0
          sn, cs = sin(angle1 + halfsweep), cos(angle1 + halfsweep)
          result = [ (cx + rx * (pxi * cs - pyi * sn),
                  cy + ry * (pxi * sn + pyi * cs))
                   for pxi, pyi in zip(px, py) ]
          return reduce(lambda x, y: x + y, result)

      epsilon = 0.01
      angle1 *= pi/180.0
      angle2 *= pi/180.0
      rotation *= pi/180.0
      sweep = angle2 - angle1
      angle1 = angle1 % (2*pi)
      sweep = min(max(-2*pi, sweep), 2*pi)

      if sweep < 0.0:
          sweep, angle1, angle2 = -sweep, angle2, angle1
      bp = [ rotation + pi/2.0 * i 
             for i in range(4) if pi/2.0 * i < sweep-epsilon ]
      bp.append(rotation + sweep)
      subarcs = [ arc_to_bezier(x, y, width/2.0, height/2.0,
                          bp[i], bp[i+1]-bp[i]) 
                for i in range(len(bp)-1) ]

      self.check_gc(gcEdge, rgbFace)
      self.file.output(subarcs[0][0], subarcs[0][1], Op.moveto)
      for arc in subarcs:
          self.file.output(*(arc[2:] + (Op.curveto,)))


    def draw_image(self, x, y, im, bbox):
        #print >>sys.stderr, "draw_image called"

      gc = self.new_gc()

      h, w = im.get_size_out()
      d = self.dpi_factor
      imob = self.file.imageObject(im)
      self.file.output(Op.gsave, d*w, 0, 0, d*h, d*x, d*y, Op.concat_matrix,
                   imob, Op.use_xobject, Op.grestore)

    def draw_line(self, gc, x1, y1, x2, y2):
      if isnan(x1) or isnan(x2) or isnan(y1) or isnan(y2):
      d = self.dpi_factor
      self.file.output(d*x1, d*y1, Op.moveto,
                   d*x2, d*y2, Op.lineto, self.gc.paint())

    def draw_lines(self, gc, x, y, transform=None):
      d = self.dpi_factor
      if transform is not None:
          x, y = transform.seq_x_y(x, y)
      nan_at = isnan(x) | isnan(y)
      next_op = Op.moveto
      for i in range(len(x)):
          if nan_at[i]:
            next_op = Op.moveto
            self.file.output(d*x[i], d*y[i], next_op)
            next_op = Op.lineto

    def draw_point(self, gc, x, y):
        print >>sys.stderr, "draw_point called"

      d = self.dpi_factor
      self.check_gc(gc, gc._rgb)
      self.file.output(d*x, d*y, d, d,
                   Op.rectangle, Op.fill_stroke)

    def draw_polygon(self, gcEdge, rgbFace, points):
      # Optimization for axis-aligned rectangles
      if len(points) == 4:
          if points[0][0] == points[1][0] and points[1][1] == points[2][1] and \
             points[2][0] == points[3][0] and points[3][1] == points[0][1]:
            self.draw_rectangle(gcEdge, rgbFace, 
                            min(points[0][0], points[2][0]),
                            min(points[1][1], points[3][1]),
                            abs(points[2][0] - points[0][0]),
                            abs(points[3][1] - points[1][1]))
          elif points[0][1] == points[1][1] and points[1][0] == points[2][0] and \
               points[2][1] == points[3][1] and points[3][0] == points[0][0]:
            self.draw_rectangle(gcEdge, rgbFace, 
                            min(points[1][0], points[3][0]),
                            min(points[2][1], points[0][1]),
                            abs(points[1][0] - points[3][0]),
                            abs(points[2][1] - points[0][1]))

      self.check_gc(gcEdge, rgbFace)
      d = self.dpi_factor
      self.file.output(d*points[0][0], d*points[0][1], Op.moveto)
      for x,y in points[1:]:
          self.file.output(d*x, d*y, Op.lineto)

    def draw_rectangle(self, gcEdge, rgbFace, x, y, width, height):
      self.check_gc(gcEdge, rgbFace)
      d = self.dpi_factor
      self.file.output(d*x, d*y, d*width, d*height, Op.rectangle)

    def draw_markers(self, gc, path, rgbFace, x, y, trans):
      self.check_gc(gc, rgbFace)
      fillp = rgbFace is not None
      marker = self.file.markerObject(path, fillp, self.gc._linewidth)
      x, y = trans.numerix_x_y(asarray(x), asarray(y))
      x, y = self.dpi_factor * x, self.dpi_factor * y
      nan_at = isnan(x) | isnan(y)

      ox, oy = 0, 0
      for i in range(len(x)):
          if nan_at[i]: continue
          dx, dy, ox, oy = x[i]-ox, y[i]-oy, x[i], y[i]
          self.file.output(1, 0, 0, 1, dx, dy, 
                       marker, Op.use_xobject)

    def _setup_textpos(self, x, y, angle, oldx=0, oldy=0, oldangle=0):
      d = self.dpi_factor
      if angle == oldangle == 0:
          self.file.output(d*(x-oldx), d*(y-oldy), Op.textpos)
          angle = angle / 180.0 * pi
          self.file.output( cos(angle), sin(angle),
                       -sin(angle), cos(angle),
                        d*x,        d*y,         Op.textmatrix)

    def draw_mathtext(self, gc, x, y, s, prop, angle):
      # TODO: fix positioning and encoding
      fontsize = prop.get_size_in_points()
      width, height, pswriter = math_parse_s_pdf(s, self.file.dpi, fontsize)

      self.check_gc(gc, gc._rgb)
      prev_font = None, None
      oldx, oldy = 0, 0
      for ox, oy, fontname, fontsize, glyph in pswriter:
          #print ox, oy, glyph
          fontname = fontname.lower()
          a = angle / 180.0 * pi
          newx = x + cos(a)*ox - sin(a)*oy
          newy = y + sin(a)*ox + cos(a)*oy
          self._setup_textpos(newx, newy, angle, oldx, oldy)
          oldx, oldy = newx, newy
          if (fontname, fontsize) != prev_font:
            self.file.output(self.file.fontName(fontname), fontsize, 
            prev_font = fontname, fontsize

          #if fontname.endswith('cmsy10.ttf') or \
          #fontname.endswith('cmmi10.ttf') or \
          # string = '\0' + chr(glyph)

          string = chr(glyph)
          self.file.output(string, Op.show)

    def draw_text(self, gc, x, y, s, prop, angle, ismath=False):
      # TODO: combine consecutive texts into one BT/ET delimited section
      #       unicode
      if isinstance(s, unicode):
          s = s.encode('ascii', 'replace')
      if ismath: return self.draw_mathtext(gc, x, y, s, prop, angle)
      self.check_gc(gc, gc._rgb)

      font = self._get_font_ttf(prop)
      font.set_text(s, 0.0)
      y += font.get_descent() / 64.0


      self._setup_textpos(x, y, angle)
      self.file.output(s, Op.show, Op.end_text)

    def get_text_width_height(self, s, prop, ismath):

      if ismath:
          fontsize = prop.get_size_in_points()
          w, h, pswriter = math_parse_s_pdf(s, self.file.dpi, fontsize)
          font = self._get_font_ttf(prop)
          font.set_text(s, 0.0)
          w, h = font.get_width_height()
          factor = 1.0/(self.dpi_factor*64.0)
          w *= factor
          h *= factor
      return w, h

    def _get_font_ttf(self, prop):
      font = self.fonts.get(prop)
      if font is None:
          font = FT2Font(fontManager.findfont(prop))
          self.fonts[prop] = font
      font.set_size(prop.get_size_in_points(), 72.0)
      return font

    def flipy(self):
        return False

    def get_canvas_width_height(self):
      d = self.dpi_factor/72.0
        return d*self.file.width, d*self.file.height

    def new_gc(self):
        return GraphicsContextPdf(self.file)

    def points_to_pixels(self, points):
        return points

class GraphicsContextPdf(GraphicsContextBase):

    def __init__(self, file):
      self._fillcolor = (0.0, 0.0, 0.0)
      self.file = file
      self.parent = None

    def __repr__(self):
      d = dict(self.__dict__)
      del d['file']
      del d['parent']
      return `d`

    def _strokep(self):
      return self._linewidth > 0 and self._alpha > 0

    def _fillp(self):
      return self._fillcolor is not None or self._hatch

    def close_and_paint(self):
      if self._strokep():
          if self._fillp(): 
            return Op.close_fill_stroke
            return Op.close_stroke
          if self._fillp():
            return Op.fill
            return Op.endpath

    def paint(self):
      if self._strokep():
          if self._fillp(): 
            return Op.fill_stroke
            return Op.stroke
          if self._fillp():
            return Op.fill
            return Op.endpath

    capstyles = { 'butt': 0, 'round': 1, 'projecting': 2 }
    joinstyles = { 'miter': 0, 'round': 1, 'bevel': 2 }

    def capstyle_cmd(self, style):
      return [self.capstyles[style], Op.setlinecap]

    def joinstyle_cmd(self, style):
      return [self.joinstyles[style], Op.setlinejoin]

    def linewidth_cmd(self, width):
      return [width, Op.setlinewidth]

    def dash_cmd(self, dashes):
      offset, dash = dashes
      if dash is None: 
          dash = []
          offset = 0
      return [list(dash), offset, Op.setdash]

    def alpha_cmd(self, alpha):
      name = self.file.alphaState(alpha)
      return [name, Op.setgstate]

    def hatch_cmd(self, hatch):
      if not hatch:
          if self._fillcolor:
            return self.fillcolor_cmd(self._fillcolor)
            return [Name('DeviceRGB'), Op.setcolorspace_nonstroke]
          hatch = hatch.lower()
          lst = ( self._rgb,
                hatch.count('-') + hatch.count('+'),
                hatch.count('/') + hatch.count('x'),
                hatch.count('|') + hatch.count('+'),
                hatch.count('\\') + hatch.count('x') )
          name = self.file.hatchPattern(lst)
          return [Name('Pattern'), Op.setcolorspace_nonstroke,
                name, Op.setcolor_nonstroke]

    def rgb_cmd(self, rgb):
      if rgb[0] == rgb[1] == rgb[2]:
          return [rgb[0], Op.setgray_stroke]
          return list(rgb) + [Op.setrgb_stroke] 

    def fillcolor_cmd(self, rgb):
      if rgb is None:
          return []
      elif rgb[0] == rgb[1] == rgb[2]:
          return [rgb[0], Op.setgray_nonstroke]
          return list(rgb) + [Op.setrgb_nonstroke] 

    def push(self):
      parent = GraphicsContextPdf(self.file)
      parent.parent = self.parent
      self.parent = parent
      return [Op.gsave]

    def pop(self):
      assert self.parent is not None
      self.parent = self.parent.parent
      return [Op.grestore]

    def cliprect_cmd(self, cliprect):
      """Set clip rectangle. Calls self.pop() and self.push()."""
      d = 72.0/self.file.dpi

      cmds = []
      while self._cliprect != cliprect and self.parent is not None:
      if self._cliprect != cliprect:
          cmds.extend(self.push() + 
                  [d*t for t in cliprect] + 
                  [Op.rectangle, Op.clip, Op.endpath])
      return cmds

    commands = (
      ('_cliprect', cliprect_cmd), # must come first since may pop
      ('_alpha', alpha_cmd),
      ('_capstyle', capstyle_cmd),
      ('_fillcolor', fillcolor_cmd),
      ('_joinstyle', joinstyle_cmd),
      ('_linewidth', linewidth_cmd),
      ('_dashes', dash_cmd),
      ('_rgb', rgb_cmd),
      ('_hatch', hatch_cmd),  # must come after fillcolor and rgb

    # TODO: _linestyle

    def copy_properties(self, other):
      """Copy properties of other into self."""
      GraphicsContextBase.copy_properties(self, other)
      self._fillcolor = other._fillcolor

    def delta(self, other):
      """Copy properties of other into self and return PDF commands 
      needed to transform self into other.
      cmds = []
      for param, cmd in self.commands:
          if getattr(self, param) != getattr(other, param):
            cmds.extend(cmd(self, getattr(other, param)))
            setattr(self, param, getattr(other, param))
      return cmds

    def finalize(self):
      """Make sure every pushed graphics state is popped."""
      cmds = []
      while self.parent is not None:
      return cmds

# The following functions and classes are for pylab and implement
# window/figure managers, etc...

def new_figure_manager(num, *args, **kwargs):
    Create a new figure manager instance
    # if a main-level app must be created, this is the usual place to
    # do it -- see backend_wx, backend_wxagg and backend_tkagg for
    # examples.  Not all GUIs require explicit instantiation of a
    # main-level app (egg backend_gtk, backend_gtkagg) for pylab
    FigureClass = kwargs.pop('FigureClass', Figure)
    thisFig = FigureClass(*args, **kwargs)
    canvas = FigureCanvasPdf(thisFig)
    manager = FigureManagerPdf(canvas, num)
    return manager

01279 class FigureCanvasPdf(FigureCanvasBase):
    The canvas the figure renders into.  Calls the draw and print fig
    methods, creates the renderers, etc...

    Public attribute

      figure - A Figure instance

#     def __init__(self, figure):
#     FigureCanvasBase.__init__(self, figure)

    def draw(self):

01295     def print_figure(self, filename, dpi=None, facecolor='w', edgecolor='w',
                     orientation='portrait', **kwargs):
        Render the figure to hardcopy. Set the figure patch face and edge
        colors.  This is useful because some of the GUIs have a gray figure
        face color background and you'll probably want to override this on

        orientation - only currently applies to PostScript printing.

      dpi - used for images
        if dpi is None:
            dpi = rcParams['savefig.dpi']
      width, height = self.figure.get_size_inches()

      basename, ext = os.path.splitext(filename)
      if ext == '': 
          filename += '.pdf'

      file = PdfFile(width, height, dpi, filename)
        renderer = RendererPdf(file)

class FigureManagerPdf(FigureManagerBase):

FigureManager = FigureManagerPdf

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