--- a
+++ b/devel/@svg/inkex.py
@@ -0,0 +1,235 @@
+#!/usr/bin/env python
+"""
+inkex.py
+A helper module for creating Inkscape extensions
+
+Copyright (C) 2005,2007 Aaron Spike, aaron@ekips.org
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+"""
+import sys, copy, optparse, random, re
+import gettext
+from math import *
+_ = gettext.gettext
+
+#a dictionary of all of the xmlns prefixes in a standard inkscape doc
+NSS = {
+u'sodipodi' :u'http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd',
+u'cc'       :u'http://creativecommons.org/ns#',
+u'ccOLD'    :u'http://web.resource.org/cc/',
+u'svg'      :u'http://www.w3.org/2000/svg',
+u'dc'       :u'http://purl.org/dc/elements/1.1/',
+u'rdf'      :u'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
+u'inkscape' :u'http://www.inkscape.org/namespaces/inkscape',
+u'xlink'    :u'http://www.w3.org/1999/xlink',
+u'xml'      :u'http://www.w3.org/XML/1998/namespace'
+}
+
+#a dictionary of unit to user unit conversion factors
+uuconv = {'in':90.0, 'pt':1.25, 'px':1, 'mm':3.5433070866, 'cm':35.433070866, 'm':3543.3070866,
+          'km':3543307.0866, 'pc':15.0, 'yd':3240 , 'ft':1080}
+def unittouu(string):
+    '''Returns userunits given a string representation of units in another system'''
+    unit = re.compile('(%s)$' % '|'.join(uuconv.keys()))
+    param = re.compile(r'(([-+]?[0-9]+(\.[0-9]*)?|[-+]?\.[0-9]+)([eE][-+]?[0-9]+)?)')
+
+    p = param.match(string)
+    u = unit.search(string)    
+    if p:
+        retval = float(p.string[p.start():p.end()])
+    else:
+        retval = 0.0
+    if u:
+        try:
+            return retval * uuconv[u.string[u.start():u.end()]]
+        except KeyError:
+            pass
+    return retval
+
+def uutounit(val, unit):
+    return val/uuconv[unit]
+
+try:
+    from lxml import etree
+except:
+    sys.exit(_('The fantastic lxml wrapper for libxml2 is required by inkex.py and therefore this extension. Please download and install the latest version from http://cheeseshop.python.org/pypi/lxml/, or install it through your package manager by a command like: sudo apt-get install python-lxml'))
+
+def debug(what):
+    sys.stderr.write(str(what) + "\n")
+    return what
+
+def errormsg(msg):
+    """Intended for end-user-visible error messages.
+    
+       (Currently just writes to stderr with an appended newline, but could do
+       something better in future: e.g. could add markup to distinguish error
+       messages from status messages or debugging output.)
+      
+       Note that this should always be combined with translation:
+
+         import gettext
+         _ = gettext.gettext
+         ...
+         inkex.errormsg(_("This extension requires two selected paths."))
+    """
+    sys.stderr.write((unicode(msg) + "\n").encode("UTF-8"))
+
+def check_inkbool(option, opt, value):
+    if str(value).capitalize() == 'True':
+        return True
+    elif str(value).capitalize() == 'False':
+        return False
+    else:
+        raise optparse.OptionValueError("option %s: invalid inkbool value: %s" % (opt, value))
+
+def addNS(tag, ns=None):
+    val = tag
+    if ns!=None and len(ns)>0 and NSS.has_key(ns) and len(tag)>0 and tag[0]!='{':
+        val = "{%s}%s" % (NSS[ns], tag)
+    return val
+
+class InkOption(optparse.Option):
+    TYPES = optparse.Option.TYPES + ("inkbool",)
+    TYPE_CHECKER = copy.copy(optparse.Option.TYPE_CHECKER)
+    TYPE_CHECKER["inkbool"] = check_inkbool
+
+class Effect:
+    """A class for creating Inkscape SVG Effects"""
+
+    def __init__(self, *args, **kwargs):
+        self.document=None
+        self.ctx=None
+        self.selected={}
+        self.doc_ids={}
+        self.options=None
+        self.args=None
+        self.OptionParser = optparse.OptionParser(usage="usage: %prog [options] SVGfile",option_class=InkOption)
+        self.OptionParser.add_option("--id",
+                        action="append", type="string", dest="ids", default=[], 
+                        help="id attribute of object to manipulate")
+
+    def effect(self):
+        pass
+
+    def getoptions(self,args=sys.argv[1:]):
+        """Collect command line arguments"""
+        self.options, self.args = self.OptionParser.parse_args(args)
+
+    def parse(self,file=None):
+        """Parse document in specified file or on stdin"""
+        try:
+            try:
+                stream = open(file,'r')
+            except:
+                stream = open(self.svg_file,'r')
+        except:
+            stream = sys.stdin
+        self.document = etree.parse(stream)
+        stream.close()
+
+    def getposinlayer(self):
+        #defaults
+        self.current_layer = self.document.getroot()
+        self.view_center = (0.0,0.0)
+
+        layerattr = self.document.xpath('//sodipodi:namedview/@inkscape:current-layer', namespaces=NSS)
+        if layerattr:
+            layername = layerattr[0]
+            layer = self.document.xpath('//svg:g[@id="%s"]' % layername, namespaces=NSS)
+            if layer:
+                self.current_layer = layer[0]
+
+        xattr = self.document.xpath('//sodipodi:namedview/@inkscape:cx', namespaces=NSS)
+        yattr = self.document.xpath('//sodipodi:namedview/@inkscape:cy', namespaces=NSS)
+        doc_height = unittouu(self.document.getroot().get('height'))
+        if xattr and yattr:
+            x = xattr[0]
+            y = yattr[0]
+            if x and y:
+                self.view_center = (float(x), doc_height - float(y)) # FIXME: y-coordinate flip, eliminate it when it's gone in Inkscape
+
+    def getselected(self):
+        """Collect selected nodes"""
+        for i in self.options.ids:
+            path = '//*[@id="%s"]' % i
+            for node in self.document.xpath(path, namespaces=NSS):
+                self.selected[i] = node
+
+    def getElementById(self, id):
+        path = '//*[@id="%s"]' % id
+        el_list = self.document.xpath(path, namespaces=NSS)
+        if el_list:
+          return el_list[0]
+        else:
+          return None
+
+    def getParentNode(self, node):
+        for parent in self.document.getiterator():
+            if node in parent.getchildren():
+                return parent
+                break
+
+
+    def getdocids(self):
+        docIdNodes = self.document.xpath('//@id', namespaces=NSS)
+        for m in docIdNodes:
+            self.doc_ids[m] = 1
+
+    def getNamedView(self):
+        return self.document.xpath('//sodipodi:namedview', namespaces=NSS)[0]
+
+    def createGuide(self, posX, posY, angle):
+        atts = {
+          'position': str(posX)+','+str(posY),
+          'orientation': str(sin(radians(angle)))+','+str(-cos(radians(angle)))
+          }
+        guide = etree.SubElement(
+                  self.getNamedView(),
+                  addNS('guide','sodipodi'), atts )
+        return guide
+
+    def output(self):
+        """Serialize document into XML on stdout"""
+        self.document.write(sys.stdout)
+
+    def affect(self, args=sys.argv[1:], output=True):
+        """Affect an SVG document with a callback effect"""
+        self.svg_file = args[-1]
+        self.getoptions(args)
+        self.parse()
+        self.getposinlayer()
+        self.getselected()
+        self.getdocids()
+        self.effect()
+        if output: self.output()
+
+    def uniqueId(self, old_id, make_new_id = True):
+        new_id = old_id
+        if make_new_id:
+            while new_id in self.doc_ids:
+                new_id += random.choice('0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ')
+            self.doc_ids[new_id] = 1
+        return new_id
+
+    def xpathSingle(self, path):
+        try:
+            retval = self.document.xpath(path, namespaces=NSS)[0]
+        except:
+            errormsg(_("No matching node for expression: %s") % path)
+            retval = None
+        return retval
+            
+
+# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99