add new extension to attach commands to objects

inx/inkstitch_commands.inx

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<inkscape-extension xmlns="http://www.inkscape.org/namespace/inkscape/extension">
+    <_name>Attach Commands</_name>
+    <id>org.inkstitch.commands</id>
+    <dependency type="executable" location="extensions">inkstitch.py</dependency>
+    <dependency type="executable" location="extensions">inkex.py</dependency>
+    <param name="fill_start" type="boolean" _gui-text="Fill starting position">false</param>
+    <param name="fill_end" type="boolean" _gui-text="Fill ending position">false</param>
+    <param name="stop" type="boolean" _gui-text="Stop after sewing this object">false</param>
+    <param name="trim" type="boolean" _gui-text="Trim thread after sewing this object">false</param>
+    <param name="extension" type="string" gui-hidden="true">commands</param>
+    <effect>
+        <object-type>all</object-type>
+        <effects-menu>
+            <submenu _name="Embroidery" />
+        </effects-menu>
+    </effect>
+    <script>
+        <command reldir="extensions" interpreter="python">inkstitch.py</command>
+    </script>
+</inkscape-extension>

lib/extensions/__init__.py

@@ -7,3 +7,4 @@ from input import Input
 from output import Output
 from zip import Zip
 from flip import Flip
+from commands import *

lib/extensions/commands.py

@@ -0,0 +1,128 @@
+import os
+import sys
+import inkex
+import simpletransform
+import cubicsuperpath
+from copy import deepcopy
+from shapely import geometry as shgeo
+
+from .base import InkstitchExtension
+from ..i18n import _
+from ..elements import SatinColumn
+from ..utils import get_bundled_dir, cache
+from ..svg.tags import SVG_DEFS_TAG, SVG_GROUP_TAG, SVG_USE_TAG, SVG_PATH_TAG, INKSCAPE_GROUPMODE, XLINK_HREF, CONNECTION_START, CONNECTION_END, CONNECTOR_TYPE
+from ..svg import get_node_transform
+
+
+class Commands(InkstitchExtension):
+    COMMANDS = ["fill_start", "fill_end", "stop", "trim"]
+
+    def __init__(self, *args, **kwargs):
+        InkstitchExtension.__init__(self, *args, **kwargs)
+        for command in self.COMMANDS:
+            self.OptionParser.add_option("--%s" % command, type="inkbool")
+
+    @property
+    def symbols_path(self):
+        return os.path.join(get_bundled_dir("symbols"), "inkstitch.svg")
+
+    @property
+    @cache
+    def symbols_svg(self):
+        with open(self.symbols_path) as symbols_file:
+            return inkex.etree.parse(symbols_file)
+
+    @property
+    @cache
+    def symbol_defs(self):
+        return self.symbols_svg.find(SVG_DEFS_TAG)
+
+    @property
+    @cache
+    def defs(self):
+        return self.document.find(SVG_DEFS_TAG)
+
+    def ensure_symbol(self, command):
+        path = "./*[@id='inkstitch_%s']" % command
+        if self.defs.find(path) is None:
+            self.defs.append(deepcopy(self.symbol_defs.find(path)))
+
+    def get_correction_transform(self, node):
+        # if we want to place our new nodes in the same group as this node,
+        # then we'll need to factor in the effects of any transforms set on
+        # the parents of this node.
+
+        # we can ignore the transform on the node itself since it won't apply
+        # to the objects we add
+        transform = get_node_transform(node.getparent())
+
+        # now invert it, so that we can position our objects in absolute
+        # coordinates
+        transform = simpletransform.invertTransform(transform)
+
+        return simpletransform.formatTransform(transform)
+
+    def add_connector(self, symbol, element):
+        # I'd like it if I could position the connector endpoint nicely but inkscape just
+        # moves it to the element's center immediately after the extension runs.
+        start_pos = (symbol.get('x'), symbol.get('y'))
+        end_pos = element.shape.centroid
+
+        path = inkex.etree.Element(SVG_PATH_TAG,
+            {
+                "id": self.uniqueId("connector"),
+                "d": "M %s,%s %s,%s" % (start_pos[0], start_pos[1], end_pos.x, end_pos.y),
+                "style": "stroke:#000000;stroke-width:1px;",
+                "transform": self.get_correction_transform(symbol),
+                CONNECTION_START: "#%s" % symbol.get('id'),
+                CONNECTION_END: "#%s" % element.node.get('id'),
+                CONNECTOR_TYPE: "polyline",
+            }
+        )
+
+        symbol.getparent().insert(symbol.getparent().index(symbol), path)
+
+    def get_command_pos(self, element, index, total):
+        # Put command symbols 30 pixels out from the shape, spaced evenly around it.
+        outline = element.shape.buffer(30).exterior
+        return outline.interpolate(index / float(total), normalized=True)
+
+    def add_command(self, element, commands):
+        for i, command in enumerate(commands):
+            pos = self.get_command_pos(element, i, len(commands))
+
+            symbol = inkex.etree.SubElement(element.node.getparent(), SVG_USE_TAG,
+                {
+                    "id": self.uniqueId("use"),
+                    XLINK_HREF: "#inkstitch_%s" % command,
+                    "height": "100%",
+                    "width": "100%",
+                    "x": str(pos.x),
+                    "y": str(pos.y),
+                    "transform": self.get_correction_transform(element.node)
+                }
+            )
+
+            self.add_connector(symbol, element)
+
+    def effect(self):
+        if not self.get_elements():
+            return
+
+        if not self.selected:
+            inkex.errormsg(_("Please select one or more objects to which to attach commands."))
+            return
+
+        self.svg = self.document.getroot()
+
+        commands = [command for command in self.COMMANDS if getattr(self.options, command)]
+
+        if not commands:
+            inkex.errormsg(_("Please choose one or more commands to attach."))
+            return
+
+        for command in commands:
+            self.ensure_symbol(command)
+
+        for element in self.elements:
+                self.add_command(element, commands)