Added dots 2 path points

extensions/fablabchemnitz_dots2pathpoints.inx

@@ -0,0 +1,35 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
+    <name>Dots 2 Path Points</name>
+    <id>fablabchemnitz.de.dots2pathpoints</id>
+    <param name="tab" type="notebook">
+        <page name="points" gui-text="Select Points">
+            <param type="bool" name="endpoints" gui-text="End Points">true</param>
+            <param type="bool" name="controlpoints" gui-text="Control Points">false</param>
+        </page>
+        <page name="usage" gui-text="Usage">
+            <label xml:space="preserve">
+This extension places an arbitrary object at the points
+of a path.
+
+Select two Objects:
+
+1. an object representing the path
+2. an object representing the dot
+
+The extension uses the SVG &lt;use&gt;-element which are
+linked to the second object. Changes of the shape of the
+source object changes the linked objects.
+            </label>
+        </page>
+    </param>
+    <effect>
+        <object-type>all</object-type>
+        <effects-menu>
+            <submenu _name="Render" />
+        </effects-menu>
+    </effect>
+    <script>
+        <command location="inx" interpreter="python">fablabchemnitz_dots2pathpoints.py</command>
+    </script>
+</inkscape-extension>

extensions/fablabchemnitz_dots2pathpoints.py

@@ -0,0 +1,76 @@
+#! /usr/bin/env python3
+'''
+Copyright (C) 2020 Christian Hoffmann christian@lehrer-hoffmann.de
+
+##This extension allows you to draw a Cartesian grid in Inkscape.
+##There is a wide range of options including subdivision, subsubdivions
+## and logarithmic scales. Custom line widths are also possible.
+##All elements are grouped with similar elements (eg all x-subdivs)
+
+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., 51 Fraanklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+'''
+
+import inkex 
+
+class Pathpoints2Dots(inkex.Effect):
+    def __init__(self):
+        inkex.Effect.__init__(self)
+        self.arg_parser.add_argument("--tab")
+        self.arg_parser.add_argument("--endpoints", type=inkex.Boolean, default=True)
+        self.arg_parser.add_argument("--controlpoints", type=inkex.Boolean, default=False)
+    
+    def effect(self):
+        if len(self.svg.selected) != 2:
+            errormsg(_("Please select exact two objects:\n1. object representing path,\n2. object representing dots."))
+            return
+    
+        dot = self.svg.selected[0]
+        iddot = dot.get('id')
+        path = self.svg.selected[1]
+        idpath = path.get('id')
+        
+        self.svg.selected.popitem()
+        self.svg.selected.popitem()
+  
+        bb = dot.bounding_box()
+        parent = path.find('..')
+        group = inkex.Group()
+        parent.add(group)
+
+        end_points = list(path.path.end_points)
+        control_points = []
+        for cp in path.path.control_points:
+            is_endpoint = False
+            for ep in end_points:
+                if cp.x == ep.x and cp.y == ep.y:
+                    is_endpoint = True
+                    break
+            if not is_endpoint:
+                control_points.append(cp)
+        
+        pointlist = []
+        if self.options.endpoints:
+            pointlist += end_points
+        if self.options.controlpoints:
+            pointlist += control_points
+        for point in pointlist:
+            clone = inkex.Use()
+            clone.set('xlink:href','#'+iddot)
+            clone.set('x',point.x-bb.center.x)
+            clone.set('y',point.y-bb.center.y)
+            group.add(clone)
+        
+if __name__ == '__main__':
+    Pathpoints2Dots().run()