Guides creator extension for Inkscape

my_guides_creator.inx

<?xml version="1.0" encoding="UTF-8"?>
<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
	<_name>My Guides Creator</_name>
	<id>net.darktrojan.myguidescreator</id>
	<dependency type="executable" location="extensions">my_guides_creator.py</dependency>
	<dependency type="executable" location="extensions">inkex.py</dependency>
	<param name="vertical_guides" type="int" min="1" max="1000" _gui-text="Columns:">2</param>
	<param name="horizontal_guides" type="int" min="1" max="1000" _gui-text="Rows:">3</param>
	<param name="guide_margin" type="int" min="0" max="20" _gui-text="Margin around guides (mm)">10</param>
	<param name="start_from_edges" type="boolean" _gui-text="Start from edges">true</param>
	<param name="delete_existing_guides" type="boolean" _gui-text="Delete existing guides">true</param>
	<effect>
		<object-type>all</object-type>
		<effects-menu>
			<submenu _name="Render"/>
		</effects-menu>
	</effect>
	<script>
		<command reldir="extensions" interpreter="python">my_guides_creator.py</command>
	</script>
</inkscape-extension>

my_guides_creator.py

#!/usr/bin/env python
import inkex


class Guides_Creator(inkex.Effect):
	def __init__(self):
		inkex.Effect.__init__(self)

		self.OptionParser.add_option(
			'--vertical_guides',
			action='store', type='string',
			dest='vertical_guides', default=1,
			help='Vertical guides each:'
		)

		self.OptionParser.add_option(
			'--horizontal_guides',
			action='store', type='string',
			dest='horizontal_guides', default=1,
			help='Horizontal guides each:'
		)

		self.OptionParser.add_option(
			'--guide_margin',
			action='store', type='string',
			dest='guide_margin', default=10
		)

		self.OptionParser.add_option(
			'--start_from_edges',
			action='store', type='inkbool',
			dest='start_from_edges', default=False,
			help='Start from edges'
		)

		self.OptionParser.add_option(
			'--delete_existing_guides',
			action='store', type='inkbool',
			dest='delete_existing_guides', default=False,
			help='Delete existing guides'
		)

	def effect(self):
		svg = self.document.getroot()

		self.width = self.unittouu(svg.get('width')) / self.unittouu('1px')
		self.height = self.unittouu(svg.get('height')) / self.unittouu('1px')
		self.from_edges = self.options.start_from_edges
		self.margin = self.unittouu(self.options.guide_margin + 'mm')

		delete_existing = self.options.delete_existing_guides
		v_division = int(self.options.vertical_guides)
		h_division = int(self.options.horizontal_guides)

		if (delete_existing):
			self.deleteAllGuides()
		self.drawVerticalGuides(v_division)
		self.drawHorizontalGuides(h_division)

	def deleteAllGuides(self):
		nv = self.document.xpath('/svg:svg/sodipodi:namedview', namespaces=inkex.NSS)[0]
		children = self.document.xpath(
			'/svg:svg/sodipodi:namedview/sodipodi:guide', namespaces=inkex.NSS
		)
		for element in children:
			nv.remove(element)

	def drawVerticalGuides(self, division):
		if division <= 0:
			return

		for v in range(0, division + 1):
			if not self.from_edges and (v == 0 or v == division):
				continue

			position_x = v * (self.width / division)
			self.createGuide(round(position_x, 4), 0, 90, color='rgb(255,0,255)')
			if self.margin > 0:
				if v != 0:
					self.createGuide(round(position_x - self.margin, 4), 0, 90)
				if v != division:
					self.createGuide(round(position_x + self.margin, 4), 0, 90)

	def drawHorizontalGuides(self, division):
		if (division <= 0):
			return

		for h in range(0, division + 1):
			if not self.from_edges and (h == 0 or h == division):
				continue

			position_y = h * (self.height / division)
			self.createGuide(0, round(position_y, 4), 0, color='rgb(255,0,255)')
			if self.margin > 0:
				if h != 0:
					self.createGuide(0, round(position_y - self.margin, 4), 0)
				if h != division:
					self.createGuide(0, round(position_y + self.margin, 4), 0)

	def createGuide(self, position_x, position_y, orientation, color=None):
		attrs = {
			'position': '%s,%s' % (str(position_x), str(position_y)),
			'orientation': '1,0' if orientation == 90 else '0,1'
		}
		if color is not None:
			attrs['{http://www.inkscape.org/namespaces/inkscape}color'] = color

		parent = self.document.find(inkex.addNS('namedview', 'sodipodi'))
		element_qname = '{http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd}guide'
		inkex.etree.SubElement(parent, element_qname, attrs)


if __name__ == '__main__':
	effect = Guides_Creator()
	effect.affect()