Openscad-Misc/gyro/path2openscad/paths2openscad.py

#!/usr/bin/env python

# openscad.py

# This is an Inkscape extension to output paths to extruded OpenSCAD polygons
# The Inkscape objects must first be converted to paths (Path > Object to Path).
# Some paths may not work well -- the paths have to be polygons.  As such,
# paths derived from text may meet with mixed results.

# Written by Daniel C. Newman ( dan dot newman at mtbaldy dot us )
# 10 June 2012

# 15 June 2012
#   Updated by Dan Newman to handle a single level of polygon nesting.
#   This is sufficient to handle most fonts.
#   If you want to nest two polygons, combine them into a single path
#   within Inkscape with "Path > Combine Path".

# 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 math
import os.path
import inkex
import simplepath
import simplestyle
import simpletransform
import cubicsuperpath
import cspsubdiv
import bezmisc
import re

DEFAULT_WIDTH = 100
DEFAULT_HEIGHT = 100

def parseLengthWithUnits( str ):

	'''
	Parse an SVG value which may or may not have units attached
	This version is greatly simplified in that it only allows: no units,
	units of px, and units of %.  Everything else, it returns None for.
	There is a more general routine to consider in scour.py if more
	generality is ever needed.
	'''

	u = 'px'
	s = str.strip()
	if s[-2:] == 'px':
		s = s[:-2]
	elif s[-1:] == '%':
		u = '%'
		s = s[:-1]

	try:
		v = float( s )
	except:
		return None, None

	return v, u

def pointInBBox( pt, bbox ):

	'''
	Determine if the point pt=[x, y] lies on or within the bounding
	box bbox=[xmin, xmax, ymin, ymax].
	'''

	# if ( x < xmin ) or ( x > xmax ) or ( y < ymin ) or ( y > ymax )
	if ( pt[0] < bbox[0] ) or ( pt[0] > bbox[1] ) or \
		( pt[1] < bbox[2] ) or ( pt[1] > bbox[3] ):
		return False
	else:
		return True

def bboxInBBox( bbox1, bbox2 ):

	'''
	Determine if the bounding box bbox1 lies on or within the
	bounding box bbox2.  NOTE: we do not test for strict enclosure.

	Structure of the bounding boxes is

	bbox1 = [ xmin1, xmax1, ymin1, ymax1 ]
	bbox2 = [ xmin2, xmax2, ymin2, ymax2 ]
	'''

	# if ( xmin1 < xmin2 ) or ( xmax1 > xmax2 ) or ( ymin1 < ymin2 ) or ( ymax1 > ymax2 )

	if ( bbox1[0] < bbox2[0] ) or ( bbox1[1] > bbox2[1] ) or \
		( bbox1[2] < bbox2[2] ) or ( bbox1[3] > bbox2[3] ):
		return False
	else:
		return True

def pointInPoly( p, poly, bbox=None ):

	'''
	Use a ray casting algorithm to see if the point p = [x, y] lies within
	the polygon poly = [[x1,y1],[x2,y2],...].  Returns True if the point
	is within poly, lies on an edge of poly, or is a vertex of poly.
	'''

	if ( p is None ) or ( poly is None ):
		return False

	# Check to see if the point lies outside the polygon's bounding box
	if not bbox is None:
		if not pointInBBox( p, bbox ):
			return False

	# Check to see if the point is a vertex
	if p in poly:
		return True

	# Handle a boundary case associated with the point
	# lying on a horizontal edge of the polygon
	x = p[0]
	y = p[1]
	p1 = poly[0]
	p2 = poly[1]
	for i in range( len( poly ) ):
		if i != 0:
			p1 = poly[i-1]
			p2 = poly[i]
		if ( y == p1[1] ) and ( p1[1] == p2[1] ) and \
			( x > min( p1[0], p2[0] ) ) and ( x < max( p1[0], p2[0] ) ):
			return True

	n = len( poly )
	inside = False

	p1_x,p1_y = poly[0]
	for i in range( n + 1 ):
		p2_x,p2_y = poly[i % n]
		if y > min( p1_y, p2_y ):
			if y <= max( p1_y, p2_y ):
				if x <= max( p1_x, p2_x ):
					if p1_y != p2_y:
						intersect = p1_x + (y - p1_y) * (p2_x - p1_x) / (p2_y - p1_y)
						if x <= intersect:
							inside = not inside
					else:
						inside = not inside
		p1_x,p1_y = p2_x,p2_y

	return inside

def polyInPoly( poly1, bbox1, poly2, bbox2 ):

	'''
	Determine if polygon poly2 = [[x1,y1],[x2,y2],...]
	contains polygon poly1.

	The bounding box information, bbox=[xmin, xmax, ymin, ymax]
	is optional.  When supplied it can be used to perform rejections.
	Note that one bounding box containing another is not sufficient
	to imply that one polygon contains another.  It's necessary, but
	not sufficient.
	'''

	# See if poly1's bboundin box is NOT contained by poly2's bounding box
	# if it isn't, then poly1 cannot be contained by poly2.

	if ( not bbox1 is None ) and ( not bbox2 is None ):
		if not bboxInBBox( bbox1, bbox2 ):
			return False

	# To see if poly1 is contained by poly2, we need to ensure that each
	# vertex of poly1 lies on or within poly2

	for p in poly1:
		if not pointInPoly( p, poly2, bbox2 ):
			return False

	# Looks like poly1 is contained on or in Poly2

	return True

def subdivideCubicPath( sp, flat, i=1 ):

	'''
	[ Lifted from eggbot.py with impunity ]

	Break up a bezier curve into smaller curves, each of which
	is approximately a straight line within a given tolerance
	(the "smoothness" defined by [flat]).

	This is a modified version of cspsubdiv.cspsubdiv(): rewritten
	because recursion-depth errors on complicated line segments
	could occur with cspsubdiv.cspsubdiv().
	'''

	while True:
		while True:
			if i >= len( sp ):
				return

			p0 = sp[i - 1][1]
			p1 = sp[i - 1][2]
			p2 = sp[i][0]
			p3 = sp[i][1]

			b = ( p0, p1, p2, p3 )

			if cspsubdiv.maxdist( b ) > flat:
				break

			i += 1

		one, two = bezmisc.beziersplitatt( b, 0.5 )
		sp[i - 1][2] = one[1]
		sp[i][0] = two[2]
		p = [one[2], one[3], two[1]]
		sp[i:1] = [p]

def closed_p(path):
	""" path[0] is the path to check """
	result = False
	thepath = path[0]
	if type(thepath[0][0]) == type([1,2]):
		result = True
	if (thepath[0][0] == thepath[-1][0]) and (thepath[0][1] == thepath[-1][1]):
		result = True
	return result

def msg_linear_extrude(id, prefix):
	msg =   '    linear_extrude(height=h)\n' + \
			'      polygon(%s_%d_points);\n' % (id,prefix)
	return msg

def msg_linear_extrude_by_paths(id, prefix):
	msg =   '    linear_extrude(height=h)\n' + \
			'      polygon(%s_%d_points, %s_%d_paths);\n' % (id, prefix, id, prefix)
	return msg

def msg_extrude_by_hull(id, prefix):
	msg =   '    for (t = [0: len(%s_%d_points)-2]) {\n' %(id,prefix) + \
			'      hull() {\n' + \
			'        translate(%s_%d_points[t]) \n' %(id,prefix) + \
			'          cylinder(h=h, r=w/2, $fn=res);\n' + \
			'        translate(%s_%d_points[t + 1]) \n' %(id,prefix) + \
			'          cylinder(h=h, r=w/2, $fn=res);\n' + \
			'      }\n' + \
			'    }\n'
	return msg




	
class OpenSCAD( inkex.Effect ):

	def __init__( self ):

		inkex.Effect.__init__( self )

		self.OptionParser.add_option( "--tab",	#NOTE: value is not used.
			action="store", type="string",
			dest="tab", default="splash",
			help="The active tab when Apply was pressed" )

		self.OptionParser.add_option("-s",'--smoothness', dest='smoothness',
			type='float', default=float( 0.2 ), action='store',
			help='Curve smoothing (less for more)' )

		self.OptionParser.add_option("-x",'--height', dest='height',
			type='string', default='5', action='store',
			help='Height (mm)' )

		self.OptionParser.add_option("-w",'--line_width', dest='line_width',
			type='float', default=float( 1 ), action='store',
			help='Line width for non closed curves (mm)' )

		self.OptionParser.add_option("-l","--force_line",
			action="store", type="inkbool",
			dest="force_line", default=False,
			help="Force line output")

		self.OptionParser.add_option("-f",'--fname', dest='fname',
			type='string', default='~/inkscape.scad',
			action='store',
			help='Curve smoothing (less for more)' )

		self.cx = float( DEFAULT_WIDTH ) / 2.0
		self.cy = float( DEFAULT_HEIGHT ) / 2.0
		self.xmin, self.xmax = ( 1.0E70, -1.0E70 )
		self.ymin, self.ymax = ( 1.0E70, -1.0E70 )

		# Dictionary of paths we will construct.  It's keyed by the SVG node
		# it came from.  Such keying isn't too useful in this specific case,
		# but it can be useful in other applications when you actually want
		# to go back and update the SVG document
		self.paths = {}

		# Output file handling
		self.call_list = []
		self.pathid    = int( 0 )

		# Output file
		self.f = None

		# For handling an SVG viewbox attribute, we will need to know the
		# values of the document's <svg> width and height attributes as well
		# as establishing a transform from the viewbox to the display.

		self.docWidth  = float( DEFAULT_WIDTH )
		self.docHeight = float( DEFAULT_HEIGHT )
		self.docTransform = [[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]

		# Dictionary of warnings issued.  This to prevent from warning
		# multiple times about the same problem
		self.warnings = {}

	def getLength( self, name, default ):

		'''
		Get the <svg> attribute with name "name" and default value "default"
		Parse the attribute into a value and associated units.  Then, accept
		units of cm, ft, in, m, mm, pc, or pt.  Convert to pixels.

		Note that SVG defines 90 px = 1 in = 25.4 mm.
		'''

		str = self.document.getroot().get( name )
		if str:
			v, u = parseLengthWithUnits( str )
			if not v:
				# Couldn't parse the value
				return None
			elif ( u == 'mm' ):
				return float( v ) * ( 90.0 / 25.4 )
			elif ( u == 'cm' ):
				return float( v ) * ( 90.0 * 10.0 / 25.4 )
			elif ( u == 'm' ):
				return float( v ) * ( 90.0 * 1000.0 / 25.4 )
			elif ( u == 'in' ):
				return float( v ) * 90.0
			elif ( u == 'ft' ):
				return float( v ) * 12.0 * 90.0
			elif ( u == 'pt' ):
				# Use modern "Postscript" points of 72 pt = 1 in instead
				# of the traditional 72.27 pt = 1 in
				return float( v ) * ( 90.0 / 72.0 )
			elif ( u == 'pc' ):
				return float( v ) * ( 90.0 / 6.0 )
			elif ( u == 'px' ):
				return float( v )
			else:
				# Unsupported units
				return None
		else:
			# No width specified; assume the default value
			return float( default )

	def getDocProps( self ):

		'''
		Get the document's height and width attributes from the <svg> tag.
		Use a default value in case the property is not present or is
		expressed in units of percentages.
		'''

		self.docHeight = self.getLength( 'height', DEFAULT_HEIGHT )
		self.docWidth = self.getLength( 'width', DEFAULT_WIDTH )
		if ( self.docHeight == None ) or ( self.docWidth == None ):
			return False
		else:
			return True

	def handleViewBox( self ):

		'''
		Set up the document-wide transform in the event that the document has an SVG viewbox
		'''

		if self.getDocProps():
			viewbox = self.document.getroot().get( 'viewBox' )
			if viewbox:
				vinfo = viewbox.strip().replace( ',', ' ' ).split( ' ' )
				if ( vinfo[2] != 0 ) and ( vinfo[3] != 0 ):
					sx = self.docWidth / float( vinfo[2] )
					sy = self.docHeight / float( vinfo[3] )
					self.docTransform = simpletransform.parseTransform( 'scale(%f,%f)' % (sx, sy) )

	def getPathVertices( self, path, node=None, transform=None ):

		'''
		Decompose the path data from an SVG element into individual
		subpaths, each subpath consisting of absolute move to and line
		to coordinates.  Place these coordinates into a list of polygon
		vertices.
		'''

		if ( not path ) or ( len( path ) == 0 ):
			# Nothing to do
			return None

		# parsePath() may raise an exception.  This is okay
		sp = simplepath.parsePath( path )
		if ( not sp ) or ( len( sp ) == 0 ):
			# Path must have been devoid of any real content
			return None

		# Get a cubic super path
		p = cubicsuperpath.CubicSuperPath( sp )
		if ( not p ) or ( len( p ) == 0 ):
			# Probably never happens, but...
			return None

		if transform:
			simpletransform.applyTransformToPath( transform, p )

		# Now traverse the cubic super path
		subpath_list = []
		subpath_vertices = []

		for sp in p:

			# We've started a new subpath
			# See if there is a prior subpath and whether we should keep it
			if len( subpath_vertices ):
				subpath_list.append( [ subpath_vertices, [ sp_xmin, sp_xmax, sp_ymin, sp_ymax ] ] )

			subpath_vertices = []
			subdivideCubicPath( sp, float( self.options.smoothness ) )

			# Note the first point of the subpath
			first_point = sp[0][1]
			subpath_vertices.append( first_point )
			sp_xmin = first_point[0]
			sp_xmax = first_point[0]
			sp_ymin = first_point[1]
			sp_ymax = first_point[1]

			# See if the first and last points are identical
			# OpenSCAD doesn't mind if we duplicate the first and last
			# vertex, but our polygon in polygon algorithm may
			n = len( sp )
			last_point = sp[n-1][1]
			#if ( first_point[0] == last_point[0] ) and ( first_point[1] == last_point[1] ):
			#	n = n - 1

			# Traverse each point of the subpath
			for csp in sp[1:n]:

				# Append the vertex to our list of vertices
				pt = csp[1]
				subpath_vertices.append( pt )

				# Track the bounding box of this subpath
				if pt[0] < sp_xmin:
					sp_xmin = pt[0]
				elif pt[0] > sp_xmax:
					sp_xmax = pt[0]
				if pt[1] < sp_ymin:
					sp_ymin = pt[1]
				elif pt[1] > sp_ymax:
					sp_ymax = pt[1]

			# Track the bounding box of the overall drawing
			# This is used for centering the polygons in OpenSCAD around the (x,y) origin
			if sp_xmin < self.xmin:
				self.xmin = sp_xmin
			if sp_xmax > self.xmax:
				self.xmax = sp_xmax
			if sp_ymin < self.ymin:
				self.ymin = sp_ymin
			if sp_ymax > self.ymax:
				self.ymax = sp_ymax

		# Handle the final subpath
		if len( subpath_vertices ):
			subpath_list.append( [ subpath_vertices, [ sp_xmin, sp_xmax, sp_ymin, sp_ymax ] ] )

		if len( subpath_list ) > 0:
			self.paths[node] = subpath_list

	def convertPath( self, node ):

		path = self.paths[node]
		if ( path is None ) or ( len( path ) == 0 ):
			return

		# Determine which polys contain which

		contains     = [ [] for i in xrange( len( path ) ) ]
		contained_by = [ [] for i in xrange( len( path ) ) ]

		for i in range( 0, len( path ) ):
			for j in range( i + 1, len( path ) ):
				if polyInPoly( path[j][0], path[j][1], path[i][0], path[i][1] ):
					# subpath i contains subpath j
					contains[i].append( j )
					# subpath j is contained in subpath i
					contained_by[j].append( i )
				elif polyInPoly( path[i][0], path[i][1], path[j][0], path[j][1] ):
					# subpath j contains subpath i
					contains[j].append( i )
					# subpath i is containd in subpath j
					contained_by[i].append( j )
		#NEW
		# create identifier
		id = node.get ( 'id', '' )
		if ( id is None ) or ( id == '' ):
			id = str( self.pathid ) + 'x'
			self.pathid += 1
		else:
			id = re.sub( '[^A-Za-z0-9_]+', '', id )
		
		# fold all subpaths into a single list of points and a number of paths by index.
		prefix = 0
		for i in range( 0, len( path ) ):
			# Skip this subpath if it is contained by another one
			if len( contained_by[i] ) != 0:
				continue
			subpath = path[i][0]
			bbox    = path[i][1]
			
			#
			poly = id + '_' + str(prefix) + '_points = ['
			polypaths = id + '_' + str(prefix) + '_paths = [['
			if len( contains[i] ) == 0:
				# This subpath does not contain any subpaths
				for point in subpath:
					poly += '[%f,%f],' % ( ( point[0] - self.cx ), ( point[1] - self.cy ) )
				poly = poly[:-1]
				poly += '];\n'
				self.f.write( poly )
				prefix += 1
			else:
				# This subpath contains other subpaths
				# collect all points into poly
				# also collect the indices into polypaths
				for point in subpath:
					poly += '[%f,%f],' % ( ( point[0] - self.cx ), ( point[1] - self.cy ) )
				count = len(subpath)
				for k in range(0, count):
					polypaths += '%d,' % (k)
				polypaths = polypaths[:-1] + '],\n\t\t\t\t['
				# The nested paths
				for j in contains[i]:
					for point in path[j][0]:
						poly += '[%f,%f],' % ( ( point[0] - self.cx ), ( point[1] - self.cy ) )
					for k in range(count, count + len(path[j][0])):
						polypaths += '%d,' % k
					count += len(path[j][0])
					polypaths = polypaths[:-1] + '],\n\t\t\t\t['
				poly = poly[:-1]
				poly += '];\n'
				polypaths = polypaths[:-7] + '];\n'
				# write the polys and paths
				self.f.write( poly )
				self.f.write( polypaths )
				prefix += 1
		# Generate an OpenSCAD module for this path
		
		self.f.write( '\nmodule poly_' + id + '(h, w, res=4)  {\n')
		self.f.write( '  scale([profile_scale, -profile_scale, 1])' )
		self.f.write( '\n  union()' ) # !!This line optional and can be removed
		self.f.write('  {\n' )

		# And add the call to the call list
		self.call_list.append( 'poly_%s(height, width);\n' % ( id ) )

		prefix = 0
		for i in range( 0, len( path ) ):

			# Skip this subpath if it is contained by another one
			if len( contained_by[i] ) != 0:
				continue
			#self.f.write( '//%s\n' % path[i][0])
			if closed_p(path[i]):
				#self.f.write( '//closed\n')
				if len( contains[i] ) == 0:
					# This subpath does not contain any subpaths
					if self.options.force_line:
						msg = msg_extrude_by_hull(id, prefix)
					else:
						msg = msg_linear_extrude(id, prefix)
					self.f.write( msg )
					prefix += 1
				else:
					# This subpath contains other subpaths
					msg = msg_linear_extrude_by_paths(id, prefix)
					self.f.write( msg )
					prefix += 1
			else:
				#self.f.write( '//open\n')
				if len( contains[i] ) == 0:
					# This subpath does not contain any subpaths
					msg = msg_extrude_by_hull(id, prefix)
					self.f.write( msg )
					prefix += 1
				else:
					# This subpath contains other subpaths
					msg = msg_linear_extrude_by_paths(id, prefix)
					self.f.write( msg )
					prefix += 1

		# End the module
		self.f.write( '  }\n' )
		self.f.write( '}\n' )

	def recursivelyTraverseSvg( self, aNodeList,
		matCurrent=[[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]],
		parent_visibility='visible' ):

		'''
		[ This too is largely lifted from eggbot.py ]

		Recursively walk the SVG document, building polygon vertex lists
		for each graphical element we support.

		Rendered SVG elements:
			<circle>, <ellipse>, <line>, <path>, <polygon>, <polyline>, <rect>

		Supported SVG elements:
			<group>, <use>

		Ignored SVG elements:
			<defs>, <eggbot>, <metadata>, <namedview>, <pattern>,
			processing directives

		All other SVG elements trigger an error (including <text>)
		'''

		for node in aNodeList:

			# Ignore invisible nodes
			v = node.get( 'visibility', parent_visibility )
			if v == 'inherit':
				v = parent_visibility
			if v == 'hidden' or v == 'collapse':
				pass

			# First apply the current matrix transform to this node's tranform
			matNew = simpletransform.composeTransform( matCurrent, simpletransform.parseTransform( node.get( "transform" ) ) )

			if node.tag == inkex.addNS( 'g', 'svg' ) or node.tag == 'g':

				self.recursivelyTraverseSvg( node, matNew, v )

			elif node.tag == inkex.addNS( 'use', 'svg' ) or node.tag == 'use':

				# A <use> element refers to another SVG element via an xlink:href="#blah"
				# attribute.  We will handle the element by doing an XPath search through
				# the document, looking for the element with the matching id="blah"
				# attribute.  We then recursively process that element after applying
				# any necessary (x,y) translation.
				#
				# Notes:
				#  1. We ignore the height and width attributes as they do not apply to
				#     path-like elements, and
				#  2. Even if the use element has visibility="hidden", SVG still calls
				#     for processing the referenced element.  The referenced element is
				#     hidden only if its visibility is "inherit" or "hidden".

				refid = node.get( inkex.addNS( 'href', 'xlink' ) )
				if not refid:
					pass

				# [1:] to ignore leading '#' in reference
				path = '//*[@id="%s"]' % refid[1:]
				refnode = node.xpath( path )
				if refnode:
					x = float( node.get( 'x', '0' ) )
					y = float( node.get( 'y', '0' ) )
					# Note: the transform has already been applied
					if ( x != 0 ) or (y != 0 ):
						matNew2 = composeTransform( matNew, parseTransform( 'translate(%f,%f)' % (x,y) ) )
					else:
						matNew2 = matNew
					v = node.get( 'visibility', v )
					self.recursivelyTraverseSvg( refnode, matNew2, v )

			elif node.tag == inkex.addNS( 'path', 'svg' ):

				path_data = node.get( 'd')
				if path_data:
					self.getPathVertices( path_data, node, matNew )

			elif node.tag == inkex.addNS( 'rect', 'svg' ) or node.tag == 'rect':

				# Manually transform
				#
				#    <rect x="X" y="Y" width="W" height="H"/>
				#
				# into
				#
				#    <path d="MX,Y lW,0 l0,H l-W,0 z"/>
				#
				# I.e., explicitly draw three sides of the rectangle and the
				# fourth side implicitly

				# Create a path with the outline of the rectangle
				x = float( node.get( 'x' ) )
				y = float( node.get( 'y' ) )
				if ( not x ) or ( not y ):
					pass
				w = float( node.get( 'width', '0' ) )
				h = float( node.get( 'height', '0' ) )
				a = []
				a.append( ['M ', [x, y]] )
				a.append( [' l ', [w, 0]] )
				a.append( [' l ', [0, h]] )
				a.append( [' l ', [-w, 0]] )
				a.append( [' Z', []] )
				self.getPathVertices( simplepath.formatPath( a ), node, matNew )

			elif node.tag == inkex.addNS( 'line', 'svg' ) or node.tag == 'line':

				# Convert
				#
				#   <line x1="X1" y1="Y1" x2="X2" y2="Y2/>
				#
				# to
				#
				#   <path d="MX1,Y1 LX2,Y2"/>

				x1 = float( node.get( 'x1' ) )
				y1 = float( node.get( 'y1' ) )
				x2 = float( node.get( 'x2' ) )
				y2 = float( node.get( 'y2' ) )
				if ( not x1 ) or ( not y1 ) or ( not x2 ) or ( not y2 ):
					pass
				a = []
				a.append( ['M ', [x1, y1]] )
				a.append( [' L ', [x2, y2]] )
				self.getPathVertices( simplepath.formatPath( a ), node, matNew )

			elif node.tag == inkex.addNS( 'polyline', 'svg' ) or node.tag == 'polyline':

				# Convert
				#
				#  <polyline points="x1,y1 x2,y2 x3,y3 [...]"/>
				#
				# to
				#
				#   <path d="Mx1,y1 Lx2,y2 Lx3,y3 [...]"/>
				#
				# Note: we ignore polylines with no points

				pl = node.get( 'points', '' ).strip()
				if pl == '':
					pass

				pa = pl.split()
				d = "".join( ["M " + pa[i] if i == 0 else " L " + pa[i] for i in range( 0, len( pa ) )] )
				self.getPathVertices( d, node, matNew )

			elif node.tag == inkex.addNS( 'polygon', 'svg' ) or node.tag == 'polygon':

				# Convert
				#
				#  <polygon points="x1,y1 x2,y2 x3,y3 [...]"/>
				#
				# to
				#
				#   <path d="Mx1,y1 Lx2,y2 Lx3,y3 [...] Z"/>
				#
				# Note: we ignore polygons with no points

				pl = node.get( 'points', '' ).strip()
				if pl == '':
					pass

				pa = pl.split()
				d = "".join( ["M " + pa[i] if i == 0 else " L " + pa[i] for i in range( 0, len( pa ) )] )
				d += " Z"
				self.getPathVertices( d, node, matNew )

			elif node.tag == inkex.addNS( 'ellipse', 'svg' ) or \
				node.tag == 'ellipse' or \
				node.tag == inkex.addNS( 'circle', 'svg' ) or \
				node.tag == 'circle':

					# Convert circles and ellipses to a path with two 180 degree arcs.
					# In general (an ellipse), we convert
					#
					#   <ellipse rx="RX" ry="RY" cx="X" cy="Y"/>
					#
					# to
					#
					#   <path d="MX1,CY A RX,RY 0 1 0 X2,CY A RX,RY 0 1 0 X1,CY"/>
					#
					# where
					#
					#   X1 = CX - RX
					#   X2 = CX + RX
					#
					# Note: ellipses or circles with a radius attribute of value 0 are ignored

					if node.tag == inkex.addNS( 'ellipse', 'svg' ) or node.tag == 'ellipse':
						rx = float( node.get( 'rx', '0' ) )
						ry = float( node.get( 'ry', '0' ) )
					else:
						rx = float( node.get( 'r', '0' ) )
						ry = rx
					if rx == 0 or ry == 0:
						pass

					cx = float( node.get( 'cx', '0' ) )
					cy = float( node.get( 'cy', '0' ) )
					x1 = cx - rx
					x2 = cx + rx
					d = 'M %f,%f ' % ( x1, cy ) + \
						'A %f,%f ' % ( rx, ry ) + \
						'0 1 0 %f,%f ' % ( x2, cy ) + \
						'A %f,%f ' % ( rx, ry ) + \
						'0 1 0 %f,%f' % ( x1, cy )
					self.getPathVertices( d, node, matNew )

			elif node.tag == inkex.addNS( 'pattern', 'svg' ) or node.tag == 'pattern':

				pass

			elif node.tag == inkex.addNS( 'metadata', 'svg' ) or node.tag == 'metadata':

				pass

			elif node.tag == inkex.addNS( 'defs', 'svg' ) or node.tag == 'defs':

				pass

			elif node.tag == inkex.addNS( 'desc', 'svg' ) or node.tag == 'desc':

				pass

			elif node.tag == inkex.addNS( 'namedview', 'sodipodi' ) or node.tag == 'namedview':

				pass

			elif node.tag == inkex.addNS( 'eggbot', 'svg' ) or node.tag == 'eggbot':

				pass

			elif node.tag == inkex.addNS( 'text', 'svg' ) or node.tag == 'text':

				inkex.errormsg( 'Warning: unable to draw text, please convert it to a path first.' )

				pass

			elif node.tag == inkex.addNS( 'title', 'svg' ) or node.tag == 'title':

				pass

			elif node.tag == inkex.addNS( 'image', 'svg' ) or node.tag == 'image':

				if not self.warnings.has_key( 'image' ):
					inkex.errormsg( gettext.gettext( 'Warning: unable to draw bitmap images; ' +
						'please convert them to line art first.  Consider using the "Trace bitmap..." ' +
						'tool of the "Path" menu.  Mac users please note that some X11 settings may ' +
						'cause cut-and-paste operations to paste in bitmap copies.' ) )
					self.warnings['image'] = 1
				pass

			elif node.tag == inkex.addNS( 'pattern', 'svg' ) or node.tag == 'pattern':

				pass

			elif node.tag == inkex.addNS( 'radialGradient', 'svg' ) or node.tag == 'radialGradient':

				# Similar to pattern
				pass

			elif node.tag == inkex.addNS( 'linearGradient', 'svg' ) or node.tag == 'linearGradient':

				# Similar in pattern
				pass

			elif node.tag == inkex.addNS( 'style', 'svg' ) or node.tag == 'style':

				# This is a reference to an external style sheet and not the value
				# of a style attribute to be inherited by child elements
				pass

			elif node.tag == inkex.addNS( 'cursor', 'svg' ) or node.tag == 'cursor':

				pass

			elif node.tag == inkex.addNS( 'color-profile', 'svg' ) or node.tag == 'color-profile':

				# Gamma curves, color temp, etc. are not relevant to single color output
				pass

			elif not isinstance( node.tag, basestring ):

				# This is likely an XML processing instruction such as an XML
				# comment.  lxml uses a function reference for such node tags
				# and as such the node tag is likely not a printable string.
				# Further, converting it to a printable string likely won't
				# be very useful.

				pass

			else:

				inkex.errormsg( 'Warning: unable to draw object <%s>, please convert it to a path first.' % node.tag )
				pass


	def recursivelyGetEnclosingTransform( self, node ):

		'''
		Determine the cumulative transform which node inherits from
		its chain of ancestors.
		'''
		node = node.getparent()
		if node is not None:
			parent_transform = self.recursivelyGetEnclosingTransform( node )
			node_transform = node.get( 'transform', None )
			if node_transform is None:
				return parent_transform
			else:
				tr = simpletransform.parseTransform( node_transform )
				if parent_transform is None:
					return tr
				else:
					return simpletransform.composeTransform( parent_transform, tr )
		else:
			return self.docTransform

	def effect( self ):

		# Viewbox handling
		self.handleViewBox()

		# First traverse the document (or selected items), reducing
		# everything to line segments.  If working on a selection,
		# then determine the selection's bounding box in the process.
		# (Actually, we just need to know it's extrema on the x-axis.)

		if self.options.ids:
			# Traverse the selected objects
			for id in self.options.ids:
				transform = self.recursivelyGetEnclosingTransform( self.selected[id] )
				self.recursivelyTraverseSvg( [self.selected[id]], transform )
		else:
			# Traverse the entire document building new, transformed paths
			self.recursivelyTraverseSvg( self.document.getroot(), self.docTransform )

		# Determine the center of the drawing's bounding box
		self.cx = self.xmin + ( self.xmax - self.xmin ) / 2.0
		self.cy = self.ymin + ( self.ymax - self.ymin ) / 2.0

		# Determine which polygons lie entirely within other polygons
		try:
			if '/' == os.sep:
				self.f = open( os.path.expanduser( self.options.fname ), 'w')
			else:
				self.f = open( os.path.expanduser( self.options.fname ).replace('/', os.sep), 'w')

			self.f.write('''
// Module names are of the form poly_<inkscape-path-id>().
// As a result you can associate a polygon in this OpenSCAD program with the
//  corresponding SVG element in the Inkscape document by looking for 
//  the XML element with the attribute id=\"inkscape-path-id\".

// Paths have their own variables so they can be imported and used 
//  in polygon(points) structures in other programs.
// The NN_points is the list of all polygon XY vertices. 
// There may be an NN_paths variable as well. If it exists then it 
//  defines the nested paths. Both must be used in the 
//  polygon(points, paths) variant of the command.

profile_scale = 25.4/90; //made in inkscape in mm

// helper functions to determine the X,Y dimensions of the profiles
function min_x(shape_points) = min([ for (x = shape_points) min(x[0])]);
function max_x(shape_points) = max([ for (x = shape_points) max(x[0])]);
function min_y(shape_points) = min([ for (x = shape_points) min(x[1])]);
function max_y(shape_points) = max([ for (x = shape_points) max(x[1])]);

''' )
			# writeout width and height
			self.f.write( 'height = %s;\n' % ( self.options.height ) )
			self.f.write( 'width = %s;\n\n' % ( self.options.line_width ) )
			
			for key in self.paths:
				self.f.write( '\n' )
				self.convertPath( key )

		# Now output the list of modules to call
			self.f.write( '\n// The shapes\n' )
			for call in self.call_list:
				self.f.write( call )

		except:
			inkex.errormsg( 'Unable to open the file ' + self.options.fname )

if __name__ == '__main__':

	e = OpenSCAD()
	e.affect()