Merge remote-tracking branch 'origin/master' into simulator-timeline

45 files changed, 694 insertions, 431 deletions

diff --git a/lib/commands.py b/lib/commands.py
index cadfa080..db3c8a71 100644
--- a/lib/commands.py
+++ b/lib/commands.py
@@ -1,8 +1,42 @@
+import sys
 import inkex
 import cubicsuperpath
+import simpletransform
 
-from .svg import apply_transforms
+from .svg import apply_transforms, get_node_transform
 from .svg.tags import SVG_USE_TAG, SVG_SYMBOL_TAG, CONNECTION_START, CONNECTION_END, XLINK_HREF
+from .utils import cache, Point
+from .i18n import _, N_
+
+COMMANDS = {
+    # L10N command attached to an object
+    N_("fill_start"): N_("Fill stitch starting position"),
+
+    # L10N command attached to an object
+    N_("fill_end"): N_("Fill stitch ending position"),
+
+    # L10N command attached to an object
+    N_("stop"): N_("Stop (pause machine) after sewing this object"),
+
+    # L10N command attached to an object
+    N_("trim"): N_("Trim thread after sewing this object"),
+
+    # L10N command attached to an object
+    N_("ignore_object"): N_("Ignore this object (do not stitch)"),
+
+    # L10N command that affects a layer
+    N_("ignore_layer"): N_("Ignore layer (do not stitch any objects in this layer)"),
+
+    # L10N command that affects entire document
+    N_("origin"): N_("Origin for exported embroidery files"),
+
+    # L10N command that affects entire document
+    N_("stop_position"): N_("Jump destination for Stop commands (a.k.a. \"Frame Out position\")."),
+}
+
+OBJECT_COMMANDS = ["fill_start", "fill_end", "stop", "trim", "ignore_object"]
+LAYER_COMMANDS = ["ignore_layer"]
+GLOBAL_COMMANDS = ["origin", "stop_position"]
 
 
 class CommandParseError(Exception):
@@ -10,6 +44,11 @@ class CommandParseError(Exception):
 
 
 class BaseCommand(object):
+    @property
+    @cache
+    def description(self):
+        return get_command_description(self.command)
+
     def parse_symbol(self):
         if self.symbol.tag != SVG_SYMBOL_TAG:
             raise CommandParseError("use points to non-symbol")
@@ -21,7 +60,7 @@ class BaseCommand(object):
         else:
             raise CommandParseError("symbol is not an Ink/Stitch command")
 
-    def get_node_by_url(self,url):
+    def get_node_by_url(self, url):
         # url will be #path12345.  Find the corresponding object.
         if url is None:
             raise CommandParseError("url is None")
@@ -87,6 +126,19 @@ class StandaloneCommand(BaseCommand):
 
         self.parse_symbol()
 
+    @property
+    @cache
+    def point(self):
+        pos = [float(self.node.get("x", 0)), float(self.node.get("y", 0))]
+        transform = get_node_transform(self.node)
+        simpletransform.applyTransformToPoint(transform, pos)
+
+        return Point(*pos)
+
+
+def get_command_description(command):
+    return COMMANDS[command]
+
 
 def find_commands(node):
     """Find the symbols this node is connected to and return them as Commands"""
@@ -106,32 +158,61 @@ def find_commands(node):
 
     return commands
 
+
 def layer_commands(layer, command):
     """Find standalone (unconnected) command symbols in this layer."""
 
-    commands = []
+    for global_command in global_commands(layer.getroottree().getroot(), command):
+        if layer in global_command.node.iterancestors():
+            yield global_command
+
+
+def global_commands(svg, command):
+    """Find standalone (unconnected) command symbols anywhere in the document."""
 
-    for standalone_command in standalone_commands(layer.getroottree().getroot()):
+    for standalone_command in _standalone_commands(svg):
         if standalone_command.command == command:
-            if layer in standalone_command.node.iterancestors():
-                commands.append(command)
+            yield standalone_command
 
-    return commands
 
-def standalone_commands(svg):
+@cache
+def global_command(svg, command):
+    """Find a single command of the specified type.
+
+    If more than one is found, print an error and exit.
+    """
+
+    commands = list(global_commands(svg, command))
+
+    if len(commands) == 1:
+        return commands[0]
+    elif len(commands) > 1:
+        print >> sys.stderr, _("Error: there is more than one %(command)s command in the document, but there can only be one.  "
+                               "Please remove all but one.") % dict(command=command)
+
+        # L10N This is a continuation of the previous error message, letting the user know
+        # what command we're talking about since we don't normally expose the actual
+        # command name to them.  Contents of %(description)s are in a separate translation
+        # string.
+        print >> sys.stderr, _("%(command)s: %(description)s") % dict(command=command, description=_(get_command_description(command)))
+
+        sys.exit(1)
+    else:
+        return None
+
+
+def _standalone_commands(svg):
     """Find all unconnected command symbols in the SVG."""
 
     xpath = ".//svg:use[starts-with(@xlink:href, '#inkstitch_')]"
     symbols = svg.xpath(xpath, namespaces=inkex.NSS)
 
-    commands = []
     for symbol in symbols:
         try:
-            commands.append(StandaloneCommand(symbol))
+            yield StandaloneCommand(symbol)
         except CommandParseError:
             pass
 
-    return commands
 
 def is_command(node):
     return CONNECTION_START in node.attrib or CONNECTION_END in node.attrib
diff --git a/lib/elements/auto_fill.py b/lib/elements/auto_fill.py
index 79220a86..cfee6d7d 100644
--- a/lib/elements/auto_fill.py
+++ b/lib/elements/auto_fill.py
@@ -31,11 +31,11 @@ class AutoFill(Fill):
 
     @property
     @param('running_stitch_length_mm',
-            _('Running stitch length (traversal between sections)'),
-            tooltip=_('Length of stitches around the outline of the fill region used when moving from section to section.'),
-            unit='mm',
-            type='float',
-            default=1.5)
+           _('Running stitch length (traversal between sections)'),
+           tooltip=_('Length of stitches around the outline of the fill region used when moving from section to section.'),
+           unit='mm',
+           type='float',
+           default=1.5)
     def running_stitch_length(self):
         return max(self.get_float_param("running_stitch_length_mm", 1.5), 0.01)
 
@@ -46,11 +46,11 @@ class AutoFill(Fill):
 
     @property
     @param('fill_underlay_angle',
-            _('Fill angle'),
-            tooltip=_('default: fill angle + 90 deg'),
-            unit='deg',
-            group=_('AutoFill Underlay'),
-            type='float')
+           _('Fill angle'),
+           tooltip=_('default: fill angle + 90 deg'),
+           unit='deg',
+           group=_('AutoFill Underlay'),
+           type='float')
     @cache
     def fill_underlay_angle(self):
         underlay_angle = self.get_float_param("fill_underlay_angle")
@@ -62,43 +62,43 @@ class AutoFill(Fill):
 
     @property
     @param('fill_underlay_row_spacing_mm',
-            _('Row spacing'),
-            tooltip=_('default: 3x fill row spacing'),
-            unit='mm',
-            group=_('AutoFill Underlay'),
-            type='float')
+           _('Row spacing'),
+           tooltip=_('default: 3x fill row spacing'),
+           unit='mm',
+           group=_('AutoFill Underlay'),
+           type='float')
     @cache
     def fill_underlay_row_spacing(self):
         return self.get_float_param("fill_underlay_row_spacing_mm") or self.row_spacing * 3
 
     @property
     @param('fill_underlay_max_stitch_length_mm',
-            _('Max stitch length'),
-            tooltip=_('default: equal to fill max stitch length'),
-            unit='mm',
-            group=_('AutoFill Underlay'), type='float')
+           _('Max stitch length'),
+           tooltip=_('default: equal to fill max stitch length'),
+           unit='mm',
+           group=_('AutoFill Underlay'), type='float')
     @cache
     def fill_underlay_max_stitch_length(self):
         return self.get_float_param("fill_underlay_max_stitch_length_mm") or self.max_stitch_length
 
     @property
     @param('fill_underlay_inset_mm',
-            _('Inset'),
-            tooltip=_('Shrink the shape before doing underlay, to prevent underlay from showing around the outside of the fill.'),
-            unit='mm',
-            group=_('AutoFill Underlay'),
-            type='float',
-            default=0)
+           _('Inset'),
+           tooltip=_('Shrink the shape before doing underlay, to prevent underlay from showing around the outside of the fill.'),
+           unit='mm',
+           group=_('AutoFill Underlay'),
+           type='float',
+           default=0)
     def fill_underlay_inset(self):
         return self.get_float_param('fill_underlay_inset_mm', 0)
 
     @property
     @param('expand_mm',
-            _('Expand'),
-            tooltip=_('Expand the shape before fill stitching, to compensate for gaps between shapes.'),
-            unit='mm',
-            type='float',
-            default=0)
+           _('Expand'),
+           tooltip=_('Expand the shape before fill stitching, to compensate for gaps between shapes.'),
+           unit='mm',
+           type='float',
+           default=0)
     def expand(self):
         return self.get_float_param('expand_mm', 0)
 
diff --git a/lib/elements/element.py b/lib/elements/element.py
index ebca90a4..4edb00c0 100644
--- a/lib/elements/element.py
+++ b/lib/elements/element.py
@@ -1,6 +1,5 @@
 import sys
 from copy import deepcopy
-from shapely import geometry as shgeo
 
 from ..i18n import _
 from ..utils import cache
@@ -8,7 +7,6 @@ from ..svg import PIXELS_PER_MM, convert_length, get_doc_size, apply_transforms
 from ..commands import find_commands
 
 # inkscape-provided utilities
-import simpletransform
 import simplestyle
 import cubicsuperpath
 from cspsubdiv import cspsubdiv
@@ -157,7 +155,7 @@ class EmbroideryElement(object):
         doc_width, doc_height = get_doc_size(svg)
         viewbox = svg.get('viewBox', '0 0 %s %s' % (doc_width, doc_height))
         viewbox = viewbox.strip().replace(',', ' ').split()
-        return  doc_width / float(viewbox[2])
+        return doc_width / float(viewbox[2])
 
     @property
     @cache
@@ -230,7 +228,7 @@ class EmbroideryElement(object):
             return commands[0]
         elif len(commands) > 1:
             raise ValueError(_("%(id)s has more than one command of type '%(command)s' linked to it") %
-                                dict(id=self.node.get(id), command=command))
+                             dict(id=self.node.get(id), command=command))
         else:
             return None
 
diff --git a/lib/elements/fill.py b/lib/elements/fill.py
index 394f523e..626573e6 100644
--- a/lib/elements/fill.py
+++ b/lib/elements/fill.py
@@ -5,7 +5,7 @@ from .element import param, EmbroideryElement, Patch
 from ..i18n import _
 from ..svg import PIXELS_PER_MM
 from ..utils import cache
-from ..stitches import running_stitch, auto_fill, legacy_fill
+from ..stitches import legacy_fill
 
 
 class Fill(EmbroideryElement):
@@ -16,21 +16,21 @@ class Fill(EmbroideryElement):
 
     @property
     @param('auto_fill',
-            _('Manually routed fill stitching'),
-            tooltip=_('AutoFill is the default method for generating fill stitching.'),
-            type='toggle',
-            inverse=True,
-            default=True)
+           _('Manually routed fill stitching'),
+           tooltip=_('AutoFill is the default method for generating fill stitching.'),
+           type='toggle',
+           inverse=True,
+           default=True)
     def auto_fill(self):
         return self.get_boolean_param('auto_fill', True)
 
     @property
     @param('angle',
-            _('Angle of lines of stitches'),
-            tooltip=_('The angle increases in a counter-clockwise direction.  0 is horizontal.  Negative angles are allowed.'),
-            unit='deg',
-            type='float',
-            default=0)
+           _('Angle of lines of stitches'),
+           tooltip=_('The angle increases in a counter-clockwise direction.  0 is horizontal.  Negative angles are allowed.'),
+           unit='deg',
+           type='float',
+           default=0)
     @cache
     def angle(self):
         return math.radians(self.get_float_param('angle', 0))
@@ -41,21 +41,23 @@ class Fill(EmbroideryElement):
         return self.get_style("fill", "#000000")
 
     @property
-    @param('flip',
-            _('Flip fill (start right-to-left)'),
-            tooltip=_('The flip option can help you with routing your stitch path.  When you enable flip, stitching goes from right-to-left instead of left-to-right.'),
-            type='boolean',
-            default=False)
+    @param(
+        'flip',
+        _('Flip fill (start right-to-left)'),
+        tooltip=_('The flip option can help you with routing your stitch path.  '
+                  'When you enable flip, stitching goes from right-to-left instead of left-to-right.'),
+        type='boolean',
+        default=False)
     def flip(self):
         return self.get_boolean_param("flip", False)
 
     @property
     @param('row_spacing_mm',
-            _('Spacing between rows'),
-            tooltip=_('Distance between rows of stitches.'),
-            unit='mm',
-            type='float',
-            default=0.25)
+           _('Spacing between rows'),
+           tooltip=_('Distance between rows of stitches.'),
+           unit='mm',
+           type='float',
+           default=0.25)
     def row_spacing(self):
         return max(self.get_float_param("row_spacing_mm", 0.25), 0.1 * PIXELS_PER_MM)
 
@@ -65,20 +67,20 @@ class Fill(EmbroideryElement):
 
     @property
     @param('max_stitch_length_mm',
-            _('Maximum fill stitch length'),
-            tooltip=_('The length of each stitch in a row.  Shorter stitch may be used at the start or end of a row.'),
-            unit='mm',
-            type='float',
-            default=3.0)
+           _('Maximum fill stitch length'),
+           tooltip=_('The length of each stitch in a row.  Shorter stitch may be used at the start or end of a row.'),
+           unit='mm',
+           type='float',
+           default=3.0)
     def max_stitch_length(self):
         return max(self.get_float_param("max_stitch_length_mm", 3.0), 0.1 * PIXELS_PER_MM)
 
     @property
     @param('staggers',
-            _('Stagger rows this many times before repeating'),
-            tooltip=_('Setting this dictates how many rows apart the stitches will be before they fall in the same column position.'),
-            type='int',
-            default=4)
+           _('Stagger rows this many times before repeating'),
+           tooltip=_('Setting this dictates how many rows apart the stitches will be before they fall in the same column position.'),
+           type='int',
+           default=4)
     def staggers(self):
         return self.get_int_param("staggers", 4)
 
diff --git a/lib/elements/polyline.py b/lib/elements/polyline.py
index b9ffdc0b..5bfe5022 100644
--- a/lib/elements/polyline.py
+++ b/lib/elements/polyline.py
@@ -1,7 +1,6 @@
 from shapely import geometry as shgeo
 
-from .element import param, EmbroideryElement, Patch
-from ..i18n import _
+from .element import EmbroideryElement, Patch
 from ..utils.geometry import Point
 from ..utils import cache
 
@@ -21,13 +20,13 @@ class Polyline(EmbroideryElement):
 
     @property
     def points(self):
-       # example: "1,2 0,0 1.5,3 4,2"
+        # example: "1,2 0,0 1.5,3 4,2"
 
-       points = self.node.get('points')
-       points = points.split(" ")
-       points = [[float(coord) for coord in point.split(",")] for point in points]
+        points = self.node.get('points')
+        points = points.split(" ")
+        points = [[float(coord) for coord in point.split(",")] for point in points]
 
-       return points
+        return points
 
     @property
     @cache
diff --git a/lib/elements/satin_column.py b/lib/elements/satin_column.py
index 834509fd..9927a606 100644
--- a/lib/elements/satin_column.py
+++ b/lib/elements/satin_column.py
@@ -29,22 +29,24 @@ class SatinColumn(EmbroideryElement):
 
     @property
     @param('zigzag_spacing_mm',
-            _('Zig-zag spacing (peak-to-peak)'),
-            tooltip=_('Peak-to-peak distance between zig-zags.'),
-            unit='mm',
-            type='float',
-            default=0.4)
+           _('Zig-zag spacing (peak-to-peak)'),
+           tooltip=_('Peak-to-peak distance between zig-zags.'),
+           unit='mm',
+           type='float',
+           default=0.4)
     def zigzag_spacing(self):
         # peak-to-peak distance between zigzags
         return max(self.get_float_param("zigzag_spacing_mm", 0.4), 0.01)
 
     @property
-    @param('pull_compensation_mm',
-            _('Pull compensation'),
-            tooltip=_('Satin stitches pull the fabric together, resulting in a column narrower than you draw in Inkscape.  This setting expands each pair of needle penetrations outward from the center of the satin column.'),
-            unit='mm',
-            type='float',
-            default=0)
+    @param(
+        'pull_compensation_mm',
+        _('Pull compensation'),
+        tooltip=_('Satin stitches pull the fabric together, resulting in a column narrower than you draw in Inkscape.  '
+                  'This setting expands each pair of needle penetrations outward from the center of the satin column.'),
+        unit='mm',
+        type='float',
+        default=0)
     def pull_compensation(self):
         # In satin stitch, the stitches have a tendency to pull together and
         # narrow the entire column.  We can compensate for this by stitching
@@ -65,12 +67,12 @@ class SatinColumn(EmbroideryElement):
 
     @property
     @param('contour_underlay_inset_mm',
-            _('Contour underlay inset amount'),
-            tooltip=_('Shrink the outline, to prevent the underlay from showing around the outside of the satin column.'),
-            unit='mm',
-            group=_('Contour Underlay'),
-            type='float',
-            default=0.4)
+           _('Contour underlay inset amount'),
+           tooltip=_('Shrink the outline, to prevent the underlay from showing around the outside of the satin column.'),
+           unit='mm',
+           group=_('Contour Underlay'),
+           type='float',
+           default=0.4)
     def contour_underlay_inset(self):
         # how far inside the edge of the column to stitch the underlay
         return self.get_float_param("contour_underlay_inset_mm", 0.4)
@@ -94,23 +96,23 @@ class SatinColumn(EmbroideryElement):
 
     @property
     @param('zigzag_underlay_spacing_mm',
-            _('Zig-Zag spacing (peak-to-peak)'),
-            tooltip=_('Distance between peaks of the zig-zags.'),
-            unit='mm',
-            group=_('Zig-zag Underlay'),
-            type='float',
-            default=3)
+           _('Zig-Zag spacing (peak-to-peak)'),
+           tooltip=_('Distance between peaks of the zig-zags.'),
+           unit='mm',
+           group=_('Zig-zag Underlay'),
+           type='float',
+           default=3)
     def zigzag_underlay_spacing(self):
         return max(self.get_float_param("zigzag_underlay_spacing_mm", 3), 0.01)
 
     @property
     @param('zigzag_underlay_inset_mm',
-            _('Inset amount'),
-            tooltip=_('default: half of contour underlay inset'),
-            unit='mm',
-            group=_('Zig-zag Underlay'),
-            type='float',
-            default="")
+           _('Inset amount'),
+           tooltip=_('default: half of contour underlay inset'),
+           unit='mm',
+           group=_('Zig-zag Underlay'),
+           type='float',
+           default="")
     def zigzag_underlay_inset(self):
         # how far in from the edge of the satin the points in the zigzags
         # should be
@@ -147,7 +149,6 @@ class SatinColumn(EmbroideryElement):
         else:
             return self.flatten_beziers_with_rungs()
 
-
     def flatten_beziers_with_rungs(self):
         input_paths = [self.flatten([path]) for path in self.csp]
         input_paths = [shgeo.LineString(path[0]) for path in input_paths]
@@ -174,18 +175,19 @@ class SatinColumn(EmbroideryElement):
             # handle null intersections here?
             linestrings = shops.split(rail, rungs)
 
-            #print >> dbg, "rails and rungs", [str(rail) for rail in rails], [str(rung) for rung in rungs]
+            # print >> dbg, "rails and rungs", [str(rail) for rail in rails], [str(rung) for rung in rungs]
             if len(linestrings.geoms) < len(rungs.geoms) + 1:
-                self.fatal(_("satin column: One or more of the rungs doesn't intersect both rails.") + "  " + _("Each rail should intersect both rungs once."))
+                self.fatal(_("satin column: One or more of the rungs doesn't intersect both rails.") +
+                           "  " + _("Each rail should intersect both rungs once."))
             elif len(linestrings.geoms) > len(rungs.geoms) + 1:
-                self.fatal(_("satin column: One or more of the rungs intersects the rails more than once.") + "  " + _("Each rail should intersect both rungs once."))
+                self.fatal(_("satin column: One or more of the rungs intersects the rails more than once.") +
+                           "  " + _("Each rail should intersect both rungs once."))
 
             paths = [[Point(*coord) for coord in ls.coords] for ls in linestrings.geoms]
             result.append(paths)
 
         return zip(*result)
 
-
     def simple_flatten_beziers(self):
         # Given a pair of paths made up of bezier segments, flatten
         # each individual bezier segment into line segments that approximate
@@ -223,8 +225,8 @@ class SatinColumn(EmbroideryElement):
 
         if len(self.csp) == 2:
             if len(self.csp[0]) != len(self.csp[1]):
-                self.fatal(_("satin column: object %(id)s has two paths with an unequal number of points (%(length1)d and %(length2)d)") % \
-                             dict(id=node_id, length1=len(self.csp[0]), length2=len(self.csp[1])))
+                self.fatal(_("satin column: object %(id)s has two paths with an unequal number of points (%(length1)d and %(length2)d)") %
+                           dict(id=node_id, length1=len(self.csp[0]), length2=len(self.csp[1])))
 
     def offset_points(self, pos1, pos2, offset_px):
         # Expand or contract two points about their midpoint.  This is
@@ -443,7 +445,6 @@ class SatinColumn(EmbroideryElement):
 
         return patch
 
-
     def to_patches(self, last_patch):
         # Stitch a variable-width satin column, zig-zagging between two paths.
 
diff --git a/lib/elements/stroke.py b/lib/elements/stroke.py
index e84d5e79..3ae2b143 100644
--- a/lib/elements/stroke.py
+++ b/lib/elements/stroke.py
@@ -28,44 +28,47 @@ class Stroke(EmbroideryElement):
 
     @property
     @param('running_stitch_length_mm',
-            _('Running stitch length'),
-            tooltip=_('Length of stitches in running stitch mode.'),
-            unit='mm',
-            type='float',
-            default=1.5,
-            sort_index=3)
+           _('Running stitch length'),
+           tooltip=_('Length of stitches in running stitch mode.'),
+           unit='mm',
+           type='float',
+           default=1.5,
+           sort_index=3)
     def running_stitch_length(self):
         return max(self.get_float_param("running_stitch_length_mm", 1.5), 0.01)
 
     @property
-    @param('bean_stitch_repeats',
-           _('Bean stitch number of repeats'),
-           tooltip=_('Backtrack each stitch this many times.  A value of 1 would triple each stitch (forward, back, forward).  A value of 2 would quintuple each stitch, etc.  Only applies to running stitch.'),
-           type='int',
-           default=0,
-           sort_index=2)
+    @param(
+        'bean_stitch_repeats',
+        _('Bean stitch number of repeats'),
+        tooltip=_('Backtrack each stitch this many times.  '
+                  'A value of 1 would triple each stitch (forward, back, forward).  '
+                  'A value of 2 would quintuple each stitch, etc.  Only applies to running stitch.'),
+        type='int',
+        default=0,
+        sort_index=2)
     def bean_stitch_repeats(self):
         return self.get_int_param("bean_stitch_repeats", 0)
 
     @property
     @param('zigzag_spacing_mm',
-            _('Zig-zag spacing (peak-to-peak)'),
-            tooltip=_('Length of stitches in zig-zag mode.'),
-            unit='mm',
-            type='float',
-            default=0.4,
-            sort_index=3)
+           _('Zig-zag spacing (peak-to-peak)'),
+           tooltip=_('Length of stitches in zig-zag mode.'),
+           unit='mm',
+           type='float',
+           default=0.4,
+           sort_index=3)
     @cache
     def zigzag_spacing(self):
         return max(self.get_float_param("zigzag_spacing_mm", 0.4), 0.01)
 
     @property
     @param('repeats',
-            _('Repeats'),
-            tooltip=_('Defines how many times to run down and back along the path.'),
-            type='int',
-            default="1",
-            sort_index=1)
+           _('Repeats'),
+           tooltip=_('Defines how many times to run down and back along the path.'),
+           type='int',
+           default="1",
+           sort_index=1)
     def repeats(self):
         return self.get_int_param("repeats", 1)
 
@@ -86,11 +89,11 @@ class Stroke(EmbroideryElement):
 
     @property
     @param('manual_stitch',
-            _('Manual stitch placement'),
-            tooltip=_("Stitch every node in the path.  Stitch length and zig-zag spacing are ignored."),
-            type='boolean',
-            default=False,
-            sort_index=0)
+           _('Manual stitch placement'),
+           tooltip=_("Stitch every node in the path.  Stitch length and zig-zag spacing are ignored."),
+           type='boolean',
+           default=False,
+           sort_index=0)
     def manual_stitch_mode(self):
         return self.get_boolean_param('manual_stitch')
 
@@ -121,9 +124,9 @@ class Stroke(EmbroideryElement):
             global warned_about_legacy_running_stitch
             if not warned_about_legacy_running_stitch:
                 warned_about_legacy_running_stitch = True
-                print >> sys.stderr, _("Legacy running stitch setting detected!\n\nIt looks like you're using a stroke " + \
-                    "smaller than 0.5 units to indicate a running stitch, which is deprecated.  Instead, please set " + \
-                    "your stroke to be dashed to indicate running stitch.  Any kind of dash will work.")
+                print >> sys.stderr, _("Legacy running stitch setting detected!\n\nIt looks like you're using a stroke " +
+                                       "smaller than 0.5 units to indicate a running stitch, which is deprecated.  Instead, please set " +
+                                       "your stroke to be dashed to indicate running stitch.  Any kind of dash will work.")
 
             # still allow the deprecated setting to work in order to support old files
             return True
@@ -174,7 +177,6 @@ class Stroke(EmbroideryElement):
 
         return Patch(self.color, stitches)
 
-
     def to_patches(self, last_patch):
         patches = []
 
diff --git a/lib/extensions/__init__.py b/lib/extensions/__init__.py
index 6c8db318..5b72ecb3 100644
--- a/lib/extensions/__init__.py
+++ b/lib/extensions/__init__.py
@@ -9,4 +9,19 @@ from zip import Zip
 from flip import Flip
 from object_commands import ObjectCommands
 from layer_commands import LayerCommands
+from global_commands import GlobalCommands
 from convert_to_satin import ConvertToSatin
+
+__all__ = extensions = [Embroider,
+                        Install,
+                        Params,
+                        Print,
+                        Simulate,
+                        Input,
+                        Output,
+                        Zip,
+                        Flip,
+                        ObjectCommands,
+                        LayerCommands,
+                        GlobalCommands,
+                        ConvertToSatin]
diff --git a/lib/extensions/base.py b/lib/extensions/base.py
index 571e3c2d..25de441f 100644
--- a/lib/extensions/base.py
+++ b/lib/extensions/base.py
@@ -3,11 +3,12 @@ import re
 import json
 from copy import deepcopy
 from collections import MutableMapping
+from stringcase import snakecase
 
-from ..svg.tags import *
+from ..svg.tags import SVG_GROUP_TAG, INKSCAPE_GROUPMODE, SVG_DEFS_TAG, EMBROIDERABLE_TAGS, SVG_POLYLINE_TAG
 from ..elements import AutoFill, Fill, Stroke, SatinColumn, Polyline, EmbroideryElement
-from ..utils import cache
 from ..commands import is_command, layer_commands
+from ..i18n import _
 
 
 SVG_METADATA_TAG = inkex.addNS("metadata", "svg")
@@ -98,17 +99,21 @@ class InkStitchMetadata(MutableMapping):
 class InkstitchExtension(inkex.Effect):
     """Base class for Inkstitch extensions.  Not intended for direct use."""
 
+    @classmethod
+    def name(cls):
+        return snakecase(cls.__name__)
+
     def hide_all_layers(self):
         for g in self.document.getroot().findall(SVG_GROUP_TAG):
             if g.get(INKSCAPE_GROUPMODE) == "layer":
                 g.set("style", "display:none")
 
     def no_elements_error(self):
-            if self.selected:
-                inkex.errormsg(_("No embroiderable paths selected."))
-            else:
-                inkex.errormsg(_("No embroiderable paths found in document."))
-            inkex.errormsg(_("Tip: use Path -> Object to Path to convert non-paths."))
+        if self.selected:
+            inkex.errormsg(_("No embroiderable paths selected."))
+        else:
+            inkex.errormsg(_("No embroiderable paths found in document."))
+        inkex.errormsg(_("Tip: use Path -> Object to Path to convert non-paths."))
 
     def descendants(self, node, selected=False):
         nodes = []
@@ -118,7 +123,7 @@ class InkstitchExtension(inkex.Effect):
             return []
 
         if node.tag == SVG_GROUP_TAG and node.get(INKSCAPE_GROUPMODE) == "layer":
-            if layer_commands(node, "ignore_layer"):
+            if len(list(layer_commands(node, "ignore_layer"))):
                 return []
 
         if element.has_style('display') and element.get_style('display') is None:
@@ -171,7 +176,6 @@ class InkstitchExtension(inkex.Effect):
 
                 return classes
 
-
     def get_elements(self):
         self.elements = []
         for node in self.get_nodes():
@@ -207,7 +211,6 @@ class InkstitchExtension(inkex.Effect):
 
         return svg_filename
 
-
     def parse(self):
         """Override inkex.Effect to add Ink/Stitch xml namespace"""
 
diff --git a/lib/extensions/commands.py b/lib/extensions/commands.py
index e3bfabfe..fb6f7874 100644
--- a/lib/extensions/commands.py
+++ b/lib/extensions/commands.py
@@ -1,5 +1,4 @@
 import os
-import sys
 import inkex
 from copy import deepcopy
 
diff --git a/lib/extensions/convert_to_satin.py b/lib/extensions/convert_to_satin.py
index dd5a9bc2..ef4ac557 100644
--- a/lib/extensions/convert_to_satin.py
+++ b/lib/extensions/convert_to_satin.py
@@ -11,6 +11,7 @@ from ..svg.tags import SVG_PATH_TAG
 from ..svg import get_correction_transform, PIXELS_PER_MM
 from ..elements import Stroke
 from ..utils import Point
+from ..i18n import _
 
 
 class SelfIntersectionError(Exception):
@@ -51,7 +52,9 @@ class ConvertToSatin(InkstitchExtension):
                 try:
                     rails, rungs = self.path_to_satin(path, element.stroke_width, style_args)
                 except SelfIntersectionError:
-                    inkex.errormsg(_("Cannot convert %s to a satin column because it intersects itself.  Try breaking it up into multiple paths.") % element.node.get('id'))
+                    inkex.errormsg(
+                        _("Cannot convert %s to a satin column because it intersects itself.  Try breaking it up into multiple paths.") %
+                        element.node.get('id'))
 
                     # revert any changes we've made
                     self.document = deepcopy(self.original_document)
@@ -84,7 +87,7 @@ class ConvertToSatin(InkstitchExtension):
         """Convert svg line join style to shapely parallel offset arguments."""
 
         args = {
-                    'join_style': shgeo.JOIN_STYLE.round
+            'join_style': shgeo.JOIN_STYLE.round
         }
 
         element_join_style = element.get_style('stroke-linejoin')
@@ -113,7 +116,7 @@ class ConvertToSatin(InkstitchExtension):
                 # path intersects itself, when taking its stroke width into consideration.  See
                 # the last example for parallel_offset() in the Shapely documentation:
                 #   https://shapely.readthedocs.io/en/latest/manual.html#object.parallel_offset
-                raise SelfIntersectionError()
+            raise SelfIntersectionError()
 
         # for whatever reason, shapely returns a right-side offset's coordinates in reverse
         left_rail = list(left_rail.coords)
@@ -244,7 +247,7 @@ class ConvertToSatin(InkstitchExtension):
             # millimeters before this one.
             if last_rung_center is not None and \
                (rung_center - last_rung_center).length() < 2 * PIXELS_PER_MM:
-                    continue
+                continue
             else:
                 last_rung_center = rung_center
 
@@ -269,7 +272,6 @@ class ConvertToSatin(InkstitchExtension):
 
         return rungs
 
-
     def satin_to_svg_node(self, rails, rungs, correction_transform):
         d = ""
         for path in chain(rails, rungs):
@@ -279,11 +281,11 @@ class ConvertToSatin(InkstitchExtension):
             d += " "
 
         return inkex.etree.Element(SVG_PATH_TAG,
-            {
-                "id": self.uniqueId("path"),
-                "style": "stroke:#000000;stroke-width:1px;fill:none",
-                "transform": correction_transform,
-                "d": d,
-                "embroider_satin_column": "true",
-            }
-        )
+                                   {
+                                       "id": self.uniqueId("path"),
+                                       "style": "stroke:#000000;stroke-width:1px;fill:none",
+                                       "transform": correction_transform,
+                                       "d": d,
+                                       "embroider_satin_column": "true",
+                                   }
+                                   )
diff --git a/lib/extensions/embroider.py b/lib/extensions/embroider.py
index 1e994e27..921201d6 100644
--- a/lib/extensions/embroider.py
+++ b/lib/extensions/embroider.py
@@ -1,7 +1,4 @@
-import sys
-import traceback
 import os
-import inkex
 
 from .base import InkstitchExtension
 from ..i18n import _
diff --git a/lib/extensions/flip.py b/lib/extensions/flip.py
index d8d78cb5..65dbdc1f 100644
--- a/lib/extensions/flip.py
+++ b/lib/extensions/flip.py
@@ -1,4 +1,3 @@
-import sys
 import inkex
 import cubicsuperpath
 from shapely import geometry as shgeo
@@ -7,6 +6,7 @@ from .base import InkstitchExtension
 from ..i18n import _
 from ..elements import SatinColumn
 
+
 class Flip(InkstitchExtension):
     def subpath_to_linestring(self, subpath):
         return shgeo.LineString()
diff --git a/lib/extensions/global_commands.py b/lib/extensions/global_commands.py
new file mode 100644
index 00000000..9655c7af
--- /dev/null
+++ b/lib/extensions/global_commands.py
@@ -0,0 +1,12 @@
+from .layer_commands import LayerCommands
+from ..commands import GLOBAL_COMMANDS
+
+
+# It's a bit weird subclassing this from LayerCommands, but global commands
+# must still be placed in a layer.  That means the two extensions
+# do the same thing and the code is the same.  We keep this as separate
+# extensions because we want the user to understand that global commands
+# affect the entire document, not just the current layer.
+
+class GlobalCommands(LayerCommands):
+    COMMANDS = GLOBAL_COMMANDS
diff --git a/lib/extensions/input.py b/lib/extensions/input.py
index cb5ac452..975ba838 100644
--- a/lib/extensions/input.py
+++ b/lib/extensions/input.py
@@ -1,15 +1,11 @@
 import os
-from os.path import realpath, dirname, join as path_join
-import sys
 from inkex import etree
 import inkex
 import pyembroidery
 
 from ..svg import PIXELS_PER_MM, render_stitch_plan
 from ..svg.tags import INKSCAPE_LABEL
-from ..i18n import _
-from ..stitch_plan import StitchPlan, ColorBlock
-from ..utils.io import save_stdout
+from ..stitch_plan import StitchPlan
 
 
 class Input(object):
@@ -28,12 +24,11 @@ class Input(object):
                                        trim=(command == pyembroidery.TRIM))
 
         extents = stitch_plan.extents
-        svg = etree.Element("svg", nsmap=inkex.NSS, attrib=
-                            {
-                                "width": str(extents[0] * 2),
-                                "height": str(extents[1] * 2),
-                                "viewBox": "0 0 %s %s" % (extents[0] * 2, extents[1] * 2),
-                            })
+        svg = etree.Element("svg", nsmap=inkex.NSS, attrib={
+            "width": str(extents[0] * 2),
+            "height": str(extents[1] * 2),
+            "viewBox": "0 0 %s %s" % (extents[0] * 2, extents[1] * 2),
+        })
         render_stitch_plan(svg, stitch_plan)
 
         # rename the Stitch Plan layer so that it doesn't get overwritten by Embroider
diff --git a/lib/extensions/install.py b/lib/extensions/install.py
index 42a92113..6c179beb 100644
--- a/lib/extensions/install.py
+++ b/lib/extensions/install.py
@@ -3,17 +3,12 @@
 import sys
 import traceback
 import os
-from os.path import realpath, dirname
 from glob import glob
-from threading import Thread
-import socket
-import errno
-import time
-import logging
 import wx
 import inkex
 
 from ..utils import guess_inkscape_config_path, get_bundled_dir
+from ..i18n import _
 
 
 class InstallerFrame(wx.Frame):
@@ -27,23 +22,24 @@ class InstallerFrame(wx.Frame):
 
         text_sizer = wx.BoxSizer(wx.HORIZONTAL)
 
-        text = _('Ink/Stitch can install files ("add-ons") that make it easier to use Inkscape to create machine embroidery designs.  These add-ons will be installed:') + \
-                 "\n\n   • " + _("thread manufacturer color palettes") + \
-                 "\n   • " + _("Ink/Stitch visual commands (Object -> Symbols...)")
+        text = (_('Ink/Stitch can install files ("add-ons") that make it easier to use Inkscape to create machine embroidery designs.  '
+                  'These add-ons will be installed:') +
+                "\n\n   • " + _("thread manufacturer color palettes") +
+                "\n   • " + _("Ink/Stitch visual commands (Object -> Symbols...)"))
 
         static_text = wx.StaticText(panel, label=text)
         font = wx.Font(12, wx.DEFAULT, wx.NORMAL, wx.NORMAL)
         static_text.SetFont(font)
-        text_sizer.Add(static_text, proportion=0, flag=wx.ALL|wx.EXPAND, border=10)
-        sizer.Add(text_sizer, proportion=3, flag=wx.ALL|wx.EXPAND, border=0)
+        text_sizer.Add(static_text, proportion=0, flag=wx.ALL | wx.EXPAND, border=10)
+        sizer.Add(text_sizer, proportion=3, flag=wx.ALL | wx.EXPAND, border=0)
 
         buttons_sizer = wx.BoxSizer(wx.HORIZONTAL)
         install_button = wx.Button(panel, wx.ID_ANY, _("Install"))
         install_button.SetBitmap(wx.ArtProvider.GetBitmap(wx.ART_TICK_MARK))
-        buttons_sizer.Add(install_button, proportion=0, flag=wx.ALIGN_RIGHT|wx.ALL, border=5)
+        buttons_sizer.Add(install_button, proportion=0, flag=wx.ALIGN_RIGHT | wx.ALL, border=5)
         cancel_button = wx.Button(panel, wx.ID_CANCEL, _("Cancel"))
-        buttons_sizer.Add(cancel_button, proportion=0, flag=wx.ALIGN_RIGHT|wx.ALL, border=5)
-        sizer.Add(buttons_sizer, proportion=1, flag=wx.ALIGN_RIGHT|wx.ALIGN_BOTTOM)
+        buttons_sizer.Add(cancel_button, proportion=0, flag=wx.ALIGN_RIGHT | wx.ALL, border=5)
+        sizer.Add(buttons_sizer, proportion=1, flag=wx.ALIGN_RIGHT | wx.ALIGN_BOTTOM)
 
         panel.SetSizer(sizer)
         panel.Layout()
@@ -63,7 +59,7 @@ class InstallerFrame(wx.Frame):
         try:
             self.install_addons('palettes')
             self.install_addons('symbols')
-        except Exception, e:
+        except Exception:
             wx.MessageDialog(self,
                              _('Inkscape add-on installation failed') + ': \n' + traceback.format_exc(),
                              _('Installation Failed'),
@@ -97,7 +93,12 @@ class InstallerFrame(wx.Frame):
             for palette_file in files:
                 shutil.copy(palette_file, dest)
 
+
 class Install(inkex.Effect):
+    @classmethod
+    def name(cls):
+        return "install"
+
     def effect(self):
         app = wx.App()
         installer_frame = InstallerFrame(None, title=_("Ink/Stitch Add-ons Installer"), size=(550, 250))
diff --git a/lib/extensions/layer_commands.py b/lib/extensions/layer_commands.py
index 88170f66..dbafc39f 100644
--- a/lib/extensions/layer_commands.py
+++ b/lib/extensions/layer_commands.py
@@ -1,15 +1,14 @@
-import os
-import sys
 import inkex
 
 from .commands import CommandsExtension
+from ..commands import LAYER_COMMANDS, get_command_description
 from ..i18n import _
-from ..svg.tags import SVG_USE_TAG, XLINK_HREF
+from ..svg.tags import SVG_USE_TAG, INKSCAPE_LABEL, XLINK_HREF
 from ..svg import get_correction_transform
 
 
 class LayerCommands(CommandsExtension):
-    COMMANDS = ["ignore_layer"]
+    COMMANDS = LAYER_COMMANDS
 
     def ensure_current_layer(self):
         # if no layer is selected, inkex defaults to the root, which isn't
@@ -34,15 +33,14 @@ class LayerCommands(CommandsExtension):
         for i, command in enumerate(commands):
             self.ensure_symbol(command)
 
-            node = inkex.etree.SubElement(self.current_layer, SVG_USE_TAG,
-                {
-                    "id": self.uniqueId("use"),
-                    XLINK_HREF: "#inkstitch_%s" % command,
-                    "height": "100%",
-                    "width": "100%",
-                    "x": str(i * 20),
-                    "y": "-10",
-                    "transform": correction_transform
-                })
-
-        namedview = self.document.xpath("//sodipodi:namedview", namespaces=inkex.NSS)
+            inkex.etree.SubElement(self.current_layer, SVG_USE_TAG,
+                                   {
+                                      "id": self.uniqueId("use"),
+                                      INKSCAPE_LABEL: _("Ink/Stitch Command") + ": %s" % get_command_description(command),
+                                      XLINK_HREF: "#inkstitch_%s" % command,
+                                      "height": "100%",
+                                      "width": "100%",
+                                      "x": str(i * 20),
+                                      "y": "-10",
+                                      "transform": correction_transform
+                                   })
diff --git a/lib/extensions/object_commands.py b/lib/extensions/object_commands.py
index 27a07969..e678890d 100644
--- a/lib/extensions/object_commands.py
+++ b/lib/extensions/object_commands.py
@@ -1,20 +1,15 @@
-import os
-import sys
 import inkex
-import simpletransform
-import cubicsuperpath
 from random import random
-from shapely import geometry as shgeo
 
 from .commands import CommandsExtension
+from ..commands import OBJECT_COMMANDS, get_command_description
 from ..i18n import _
-from ..elements import SatinColumn
-from ..svg.tags import SVG_GROUP_TAG, SVG_USE_TAG, SVG_PATH_TAG, INKSCAPE_GROUPMODE, XLINK_HREF, CONNECTION_START, CONNECTION_END, CONNECTOR_TYPE
+from ..svg.tags import SVG_PATH_TAG, CONNECTION_START, CONNECTION_END, CONNECTOR_TYPE, INKSCAPE_LABEL, SVG_GROUP_TAG, SVG_USE_TAG, XLINK_HREF
 from ..svg import get_correction_transform
 
 
 class ObjectCommands(CommandsExtension):
-    COMMANDS = ["fill_start", "fill_end", "stop", "trim", "ignore_object"]
+    COMMANDS = OBJECT_COMMANDS
 
     def add_connector(self, symbol, element):
         # I'd like it if I could position the connector endpoint nicely but inkscape just
@@ -23,18 +18,20 @@ class ObjectCommands(CommandsExtension):
         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;stroke-opacity:0.5;fill:none;",
-                "transform": get_correction_transform(symbol),
-                CONNECTION_START: "#%s" % symbol.get('id'),
-                CONNECTION_END: "#%s" % element.node.get('id'),
-                CONNECTOR_TYPE: "polyline",
-            }
-        )
+                                   {
+                                       "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;stroke-opacity:0.5;fill:none;",
+                                       CONNECTION_START: "#%s" % symbol.get('id'),
+                                       CONNECTION_END: "#%s" % element.node.get('id'),
+                                       CONNECTOR_TYPE: "polyline",
+
+                                       # l10n: the name of the line that connects a command to the object it applies to
+                                       INKSCAPE_LABEL: _("connector")
+                                   }
+                                   )
 
-        symbol.getparent().insert(symbol.getparent().index(symbol), path)
+        symbol.getparent().insert(0, path)
 
     def get_command_pos(self, element, index, total):
         # Put command symbols 30 pixels out from the shape, spaced evenly around it.
@@ -71,18 +68,28 @@ class ObjectCommands(CommandsExtension):
 
             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": get_correction_transform(element.node)
-                }
+            group = inkex.etree.SubElement(element.node.getparent(), SVG_GROUP_TAG,
+                                           {
+                "id": self.uniqueId("group"),
+                INKSCAPE_LABEL: _("Ink/Stitch Command") + ": %s" % get_command_description(command),
+                "transform": get_correction_transform(element.node)
+            }
             )
 
+            symbol = inkex.etree.SubElement(group, SVG_USE_TAG,
+                                            {
+                                                "id": self.uniqueId("use"),
+                                                XLINK_HREF: "#inkstitch_%s" % command,
+                                                "height": "100%",
+                                                "width": "100%",
+                                                "x": str(pos.x),
+                                                "y": str(pos.y),
+
+                                                # l10n: the name of a command symbol (example: scissors icon for trim command)
+                                                INKSCAPE_LABEL: _("command marker"),
+                                            }
+                                            )
+
             self.add_connector(symbol, element)
 
     def effect(self):
diff --git a/lib/extensions/output.py b/lib/extensions/output.py
index f3bb0a80..26fd4f2e 100644
--- a/lib/extensions/output.py
+++ b/lib/extensions/output.py
@@ -1,15 +1,12 @@
 import sys
-import traceback
 import os
-import inkex
 import tempfile
 
 from .base import InkstitchExtension
-from ..i18n import _
 from ..output import write_embroidery_file
 from ..stitch_plan import patches_to_stitch_plan
-from ..svg import render_stitch_plan, PIXELS_PER_MM
-from ..utils.io import save_stdout
+from ..svg import PIXELS_PER_MM
+
 
 class Output(InkstitchExtension):
     def __init__(self, *args, **kwargs):
diff --git a/lib/extensions/print_pdf.py b/lib/extensions/print_pdf.py
index 6e2eff58..d2e2365d 100644
--- a/lib/extensions/print_pdf.py
+++ b/lib/extensions/print_pdf.py
@@ -1,5 +1,4 @@
 import sys
-import traceback
 import os
 from threading import Thread
 import socket
@@ -13,15 +12,14 @@ import json
 import inkex
 from jinja2 import Environment, FileSystemLoader, select_autoescape
 from datetime import date
-import base64
 from flask import Flask, request, Response, send_from_directory, jsonify
 import webbrowser
 import requests
 
 from .base import InkstitchExtension
 from ..i18n import _, translation as inkstitch_translation
-from ..svg import PIXELS_PER_MM, render_stitch_plan
-from ..svg.tags import SVG_GROUP_TAG, INKSCAPE_GROUPMODE
+from ..svg import render_stitch_plan
+from ..svg.tags import INKSCAPE_GROUPMODE
 from ..stitch_plan import patches_to_stitch_plan
 from ..threads import ThreadCatalog
 
@@ -44,7 +42,7 @@ def load_defaults():
         with open(defaults_path(), 'r') as defaults_file:
             defaults = json.load(defaults_file)
             return defaults
-    except:
+    except BaseException:
         return {}
 
 
@@ -109,7 +107,7 @@ class PrintPreviewServer(Thread):
         else:
             self.resources_path = os.path.realpath(os.path.join(os.path.dirname(__file__), '..', '..', 'print', 'resources'))
 
-    def __setup_app(self):
+    def __setup_app(self):  # noqa: C901
         self.__set_resources_path()
         self.app = Flask(__name__)
 
@@ -196,11 +194,11 @@ class PrintPreviewServer(Thread):
             threads = []
             for color_block in self.stitch_plan:
                 threads.append({
-                                'hex': color_block.color.hex_digits,
-                                'name': color_block.color.name,
-                                'manufacturer': color_block.color.manufacturer,
-                                'number': color_block.color.number,
-                             })
+                    'hex': color_block.color.hex_digits,
+                    'name': color_block.color.name,
+                    'manufacturer': color_block.color.manufacturer,
+                    'number': color_block.color.number,
+                })
 
             return jsonify(threads)
 
@@ -225,10 +223,10 @@ class PrintPreviewServer(Thread):
                     break
 
                 if self.last_request_time is not None and \
-                    (time.time() - self.last_request_time) > 3:
-                        self.stop()
-                        break
-        except:
+                        (time.time() - self.last_request_time) > 3:
+                    self.stop()
+                    break
+        except BaseException:
             # seems like sometimes this thread blows up during shutdown
             pass
 
@@ -244,7 +242,7 @@ class PrintPreviewServer(Thread):
         while True:
             try:
                 self.app.run(self.host, self.port, threaded=True)
-            except socket.error, e:
+            except socket.error as e:
                 if e.errno == errno.EADDRINUSE:
                     self.port += 1
                     continue
@@ -262,14 +260,17 @@ class PrintInfoFrame(wx.Frame):
         panel = wx.Panel(self)
         sizer = wx.BoxSizer(wx.VERTICAL)
 
-        text = wx.StaticText(panel, label=_("A print preview has been opened in your web browser.  This window will stay open in order to communicate with the JavaScript code running in your browser.\n\nThis window will close after you close the print preview in your browser, or you can close it manually if necessary."))
+        message = _("A print preview has been opened in your web browser.  "
+                    "This window will stay open in order to communicate with the JavaScript code running in your browser.\n\n"
+                    "This window will close after you close the print preview in your browser, or you can close it manually if necessary.")
+        text = wx.StaticText(panel, label=message)
         font = wx.Font(14, wx.DEFAULT, wx.NORMAL, wx.NORMAL)
         text.SetFont(font)
-        sizer.Add(text, proportion=1, flag=wx.ALL|wx.EXPAND, border=20)
+        sizer.Add(text, proportion=1, flag=wx.ALL | wx.EXPAND, border=20)
 
         stop_button = wx.Button(panel, id=wx.ID_CLOSE)
         stop_button.Bind(wx.EVT_BUTTON, self.close_button_clicked)
-        sizer.Add(stop_button, proportion=0, flag=wx.ALIGN_CENTER|wx.ALL, border=10)
+        sizer.Add(stop_button, proportion=0, flag=wx.ALIGN_CENTER | wx.ALL, border=10)
 
         panel.SetSizer(sizer)
         panel.Layout()
@@ -289,13 +290,13 @@ class PrintInfoFrame(wx.Frame):
 
 class Print(InkstitchExtension):
     def build_environment(self):
-        if getattr( sys, 'frozen', False ) :
+        if getattr(sys, 'frozen', False):
             template_dir = os.path.join(sys._MEIPASS, "print", "templates")
         else:
             template_dir = os.path.realpath(os.path.join(os.path.dirname(__file__), "..", "..", "print", "templates"))
 
         env = Environment(
-            loader = FileSystemLoader(template_dir),
+            loader=FileSystemLoader(template_dir),
             autoescape=select_autoescape(['html', 'xml']),
             extensions=['jinja2.ext.i18n']
         )
@@ -308,8 +309,8 @@ class Print(InkstitchExtension):
     def strip_namespaces(self, svg):
         # namespace prefixes seem to trip up HTML, so get rid of them
         for element in svg.iter():
-            if element.tag[0]=='{':
-                element.tag = element.tag[element.tag.index('}',1) + 1:]
+            if element.tag[0] == '{':
+                element.tag = element.tag[element.tag.index('}', 1) + 1:]
 
     def render_svgs(self, stitch_plan, realistic=False):
         svg = deepcopy(self.document).getroot()
@@ -352,25 +353,25 @@ class Print(InkstitchExtension):
         template = env.get_template('index.html')
 
         return template.render(
-            view = {'client_overview': False, 'client_detailedview': False, 'operator_overview': True, 'operator_detailedview': True},
-            logo = {'src' : '', 'title' : 'LOGO'},
-            date = date.today(),
-            client = "",
-            job = {
-                    'title': '',
-                    'num_colors': stitch_plan.num_colors,
-                    'num_color_blocks': len(stitch_plan),
-                    'num_stops': stitch_plan.num_stops,
-                    'num_trims': stitch_plan.num_trims,
-                    'dimensions': stitch_plan.dimensions_mm,
-                    'num_stitches': stitch_plan.num_stitches,
-                    'estimated_time': '', # TODO
-                    'estimated_thread': '', # TODO
-                  },
-            svg_overview = overview_svg,
-            color_blocks = stitch_plan.color_blocks,
-            palettes = ThreadCatalog().palette_names(),
-            selected_palette = selected_palette,
+            view={'client_overview': False, 'client_detailedview': False, 'operator_overview': True, 'operator_detailedview': True},
+            logo={'src': '', 'title': 'LOGO'},
+            date=date.today(),
+            client="",
+            job={
+                'title': '',
+                'num_colors': stitch_plan.num_colors,
+                'num_color_blocks': len(stitch_plan),
+                'num_stops': stitch_plan.num_stops,
+                'num_trims': stitch_plan.num_trims,
+                'dimensions': stitch_plan.dimensions_mm,
+                'num_stitches': stitch_plan.num_stitches,
+                'estimated_time': '',  # TODO
+                'estimated_thread': '',  # TODO
+            },
+            svg_overview=overview_svg,
+            color_blocks=stitch_plan.color_blocks,
+            palettes=ThreadCatalog().palette_names(),
+            selected_palette=selected_palette,
         )
 
     def effect(self):
@@ -396,12 +397,12 @@ class Print(InkstitchExtension):
         html = self.render_html(stitch_plan, overview_svg, palette)
 
         print_server = PrintPreviewServer(
-                        html=html,
-                        metadata=self.get_inkstitch_metadata(),
-                        stitch_plan=stitch_plan,
-                        realistic_overview_svg=realistic_overview_svg,
-                        realistic_color_block_svgs=realistic_color_block_svgs
-                       )
+            html=html,
+            metadata=self.get_inkstitch_metadata(),
+            stitch_plan=stitch_plan,
+            realistic_overview_svg=realistic_overview_svg,
+            realistic_color_block_svgs=realistic_color_block_svgs
+        )
         print_server.start()
 
         time.sleep(1)
diff --git a/lib/extensions/zip.py b/lib/extensions/zip.py
index 02f29e8a..2376f79a 100644
--- a/lib/extensions/zip.py
+++ b/lib/extensions/zip.py
@@ -1,7 +1,5 @@
 import sys
-import traceback
 import os
-import inkex
 import tempfile
 from zipfile import ZipFile
 import pyembroidery
@@ -10,8 +8,7 @@ from .base import InkstitchExtension
 from ..i18n import _
 from ..output import write_embroidery_file
 from ..stitch_plan import patches_to_stitch_plan
-from ..svg import render_stitch_plan, PIXELS_PER_MM
-from ..utils.io import save_stdout
+from ..svg import PIXELS_PER_MM
 
 
 class Zip(InkstitchExtension):
diff --git a/lib/i18n.py b/lib/i18n.py
index d20f5d2f..045fa1b2 100644
--- a/lib/i18n.py
+++ b/lib/i18n.py
@@ -1,21 +1,37 @@
 import sys
 import os
+from os.path import dirname, realpath
 import gettext
 
 _ = translation = None
+locale_dir = None
+
+# Use N_ to mark a string for translation but _not_ immediately translate it.
+# reference: https://docs.python.org/3/library/gettext.html#deferred-translations
+# Makefile configures pybabel to treat N_() the same as _()
+
+
+def N_(message): return message
+
+
+def _set_locale_dir():
+    global locale_dir
 
-def localize():
     if getattr(sys, 'frozen', False):
         # we are in a pyinstaller installation
         locale_dir = sys._MEIPASS
     else:
-        locale_dir = os.path.dirname(__file__)
+        locale_dir = dirname(dirname(realpath(__file__)))
 
     locale_dir = os.path.join(locale_dir, 'locales')
 
+
+def localize(languages=None):
     global translation, _
 
     translation = gettext.translation("inkstitch", locale_dir, fallback=True)
     _ = translation.gettext
 
+
+_set_locale_dir()
 localize()
diff --git a/lib/inx/__init__.py b/lib/inx/__init__.py
new file mode 100644
index 00000000..32b8bfae
--- /dev/null
+++ b/lib/inx/__init__.py
@@ -0,0 +1 @@
+from generate import generate_inx_files
diff --git a/lib/inx/extensions.py b/lib/inx/extensions.py
new file mode 100755
index 00000000..d1a0c7f3
--- /dev/null
+++ b/lib/inx/extensions.py
@@ -0,0 +1,43 @@
+import pyembroidery
+
+from .utils import build_environment, write_inx_file
+from .outputs import pyembroidery_output_formats
+from ..extensions import extensions, Input, Output
+from ..commands import LAYER_COMMANDS, OBJECT_COMMANDS, GLOBAL_COMMANDS, COMMANDS
+
+
+def layer_commands():
+    # We purposefully avoid using commands.get_command_description() here.  We
+    # want to call _() on the description inside the actual template so that
+    # we use the translation language selected in build_environment().
+    return [(command, COMMANDS[command]) for command in LAYER_COMMANDS]
+
+
+def global_commands():
+    return [(command, COMMANDS[command]) for command in GLOBAL_COMMANDS]
+
+
+def object_commands():
+    return [(command, COMMANDS[command]) for command in OBJECT_COMMANDS]
+
+
+def pyembroidery_debug_formats():
+    for format in pyembroidery.supported_formats():
+        if 'writer' in format and format['category'] != 'embroidery':
+            yield format['extension'], format['description']
+
+
+def generate_extension_inx_files():
+    env = build_environment()
+
+    for extension in extensions:
+        if extension is Input or extension is Output:
+            continue
+
+        name = extension.name()
+        template = env.get_template('%s.inx' % name)
+        write_inx_file(name, template.render(formats=pyembroidery_output_formats(),
+                                             debug_formats=pyembroidery_debug_formats(),
+                                             layer_commands=layer_commands(),
+                                             object_commands=object_commands(),
+                                             global_commands=global_commands()))
diff --git a/lib/inx/generate.py b/lib/inx/generate.py
new file mode 100644
index 00000000..941596de
--- /dev/null
+++ b/lib/inx/generate.py
@@ -0,0 +1,11 @@
+from .inputs import generate_input_inx_files
+from .outputs import generate_output_inx_files
+from .extensions import generate_extension_inx_files
+from .utils import iterate_inx_locales
+
+
+def generate_inx_files():
+    for locale in iterate_inx_locales():
+        generate_input_inx_files()
+        generate_output_inx_files()
+        generate_extension_inx_files()
diff --git a/lib/inx/inputs.py b/lib/inx/inputs.py
new file mode 100755
index 00000000..d40ffeaf
--- /dev/null
+++ b/lib/inx/inputs.py
@@ -0,0 +1,18 @@
+import pyembroidery
+
+from .utils import build_environment, write_inx_file
+
+
+def pyembroidery_input_formats():
+    for format in pyembroidery.supported_formats():
+        if 'reader' in format and format['category'] == 'embroidery':
+            yield format['extension'], format['description']
+
+
+def generate_input_inx_files():
+    env = build_environment()
+    template = env.get_template('input.inx')
+
+    for format, description in pyembroidery_input_formats():
+        name = "input_%s" % format.upper()
+        write_inx_file(name, template.render(format=format, description=description))
diff --git a/lib/inx/outputs.py b/lib/inx/outputs.py
new file mode 100644
index 00000000..aef0c8b5
--- /dev/null
+++ b/lib/inx/outputs.py
@@ -0,0 +1,18 @@
+import pyembroidery
+
+from .utils import build_environment, write_inx_file
+
+
+def pyembroidery_output_formats():
+    for format in pyembroidery.supported_formats():
+        if 'writer' in format and format['category'] == 'embroidery':
+            yield format['extension'], format['description']
+
+
+def generate_output_inx_files():
+    env = build_environment()
+    template = env.get_template('output.inx')
+
+    for format, description in pyembroidery_output_formats():
+        name = "output_%s" % format.upper()
+        write_inx_file(name, template.render(format=format, description=description))
diff --git a/lib/inx/utils.py b/lib/inx/utils.py
new file mode 100644
index 00000000..54b37c58
--- /dev/null
+++ b/lib/inx/utils.py
@@ -0,0 +1,52 @@
+import os
+import gettext
+from os.path import dirname
+from jinja2 import Environment, FileSystemLoader
+
+from ..i18n import translation as default_translation, locale_dir, N_
+
+
+_top_path = dirname(dirname(dirname(os.path.realpath(__file__))))
+inx_path = os.path.join(_top_path, "inx")
+template_path = os.path.join(_top_path, "templates")
+
+current_translation = default_translation
+current_locale = "en_US"
+
+
+def build_environment():
+    env = Environment(
+        loader=FileSystemLoader(template_path),
+        autoescape=True,
+        extensions=['jinja2.ext.i18n']
+    )
+
+    env.install_gettext_translations(current_translation)
+    env.globals["locale"] = current_locale
+
+    return env
+
+
+def write_inx_file(name, contents):
+    inx_file_name = "inkstitch_%s_%s.inx" % (name, current_locale)
+    with open(os.path.join(inx_path, inx_file_name), 'w') as inx_file:
+        print >> inx_file, contents.encode("utf-8")
+
+
+def iterate_inx_locales():
+    global current_translation, current_locale
+
+    locales = sorted(os.listdir(locale_dir))
+    for locale in locales:
+        translation = gettext.translation("inkstitch", locale_dir, languages=[locale], fallback=True)
+
+        # L10N If you translate this string, that will tell Ink/Stitch to
+        # generate menu items for this language in Inkscape's "Extensions"
+        # menu.
+        magic_string = N_("Generate INX files")
+        translated_magic_string = translation.gettext(magic_string)
+
+        if translated_magic_string != magic_string or locale == "en_US":
+            current_translation = translation
+            current_locale = locale
+            yield locale
diff --git a/lib/output.py b/lib/output.py
index 0d7f9918..d5c513e2 100644
--- a/lib/output.py
+++ b/lib/output.py
@@ -1,10 +1,9 @@
 import pyembroidery
-import inkex
 import simpletransform
-import shapely.geometry as shgeo
 
 from .utils import Point
 from .svg import PIXELS_PER_MM, get_doc_size, get_viewbox_transform
+from .commands import global_command
 
 
 def get_command(stitch):
@@ -19,65 +18,37 @@ def get_command(stitch):
     else:
         return pyembroidery.NEEDLE_AT
 
+
 def _string_to_floats(string):
     floats = string.split(',')
     return [float(num) for num in floats]
 
 
 def get_origin(svg):
-    # The user can specify the embroidery origin by defining two guides
-    # named "embroidery origin" that intersect.
+    origin_command = global_command(svg, "origin")
 
-    namedview = svg.find(inkex.addNS('namedview', 'sodipodi'))
-    all_guides = namedview.findall(inkex.addNS('guide', 'sodipodi'))
-    label_attribute = inkex.addNS('label', 'inkscape')
-    guides = [guide for guide in all_guides
-                    if guide.get(label_attribute, "").startswith("embroidery origin")]
+    if origin_command:
+        return origin_command.point
+    else:
+        # default: center of the canvas
 
-    # document size used below
-    doc_size = list(get_doc_size(svg))
+        doc_size = list(get_doc_size(svg))
 
-    # convert the size from viewbox-relative to real-world pixels
-    viewbox_transform = get_viewbox_transform(svg)
-    simpletransform.applyTransformToPoint(simpletransform.invertTransform(viewbox_transform), doc_size)
+        # convert the size from viewbox-relative to real-world pixels
+        viewbox_transform = get_viewbox_transform(svg)
+        simpletransform.applyTransformToPoint(simpletransform.invertTransform(viewbox_transform), doc_size)
 
-    default = [doc_size[0] / 2.0, doc_size[1] / 2.0]
-    simpletransform.applyTransformToPoint(viewbox_transform, default)
-    default = Point(*default)
+        default = [doc_size[0] / 2.0, doc_size[1] / 2.0]
+        simpletransform.applyTransformToPoint(viewbox_transform, default)
+        default = Point(*default)
 
-    if len(guides) < 2:
         return default
 
-    # Find out where the guides intersect.  Only pay attention to the first two.
-    guides = guides[:2]
-
-    lines = []
-    for guide in guides:
-        # inkscape's Y axis is reversed from SVG's, and the guide is in inkscape coordinates
-        position = Point(*_string_to_floats(guide.get('position')))
-        position.y = doc_size[1] - position.y
-
-
-        # This one baffles me.  I think inkscape might have gotten the order of
-        # their vector wrong?
-        parts = _string_to_floats(guide.get('orientation'))
-        direction = Point(parts[1], parts[0])
 
-        # We have a theoretically infinite line defined by a point on the line
-        # and a vector direction.  Shapely can only deal in concrete line
-        # segments, so we'll pick points really far in either direction on the
-        # line and call it good enough.
-        lines.append(shgeo.LineString((position + 100000 * direction, position - 100000 * direction)))
-
-    intersection = lines[0].intersection(lines[1])
-
-    if isinstance(intersection, shgeo.Point):
-        origin = [intersection.x, intersection.y]
-        simpletransform.applyTransformToPoint(viewbox_transform, origin)
-        return Point(*origin)
-    else:
-        # Either the two guides are the same line, or they're parallel.
-        return default
+def jump_to_stop_point(pattern, svg):
+    stop_position = global_command(svg, "stop_position")
+    if stop_position:
+        pattern.add_stitch_absolute(pyembroidery.JUMP, stop_position.point.x, stop_position.point.y)
 
 
 def write_embroidery_file(file_path, stitch_plan, svg):
@@ -89,6 +60,8 @@ def write_embroidery_file(file_path, stitch_plan, svg):
         pattern.add_thread(color_block.color.pyembroidery_thread)
 
         for stitch in color_block:
+            if stitch.stop:
+                jump_to_stop_point(pattern, svg)
             command = get_command(stitch)
             pattern.add_stitch_absolute(command, stitch.x, stitch.y)
 
@@ -98,17 +71,17 @@ def write_embroidery_file(file_path, stitch_plan, svg):
     # also multiply by 10 to get tenths of a millimeter as required by pyembroidery
     scale = 10 / PIXELS_PER_MM
 
-    settings =  {
-                    # correct for the origin
-                    "translate": -origin,
+    settings = {
+        # correct for the origin
+        "translate": -origin,
 
-                    # convert from pixels to millimeters
-                    # also multiply by 10 to get tenths of a millimeter as required by pyembroidery
-                    "scale": (scale, scale),
+        # convert from pixels to millimeters
+        # also multiply by 10 to get tenths of a millimeter as required by pyembroidery
+        "scale": (scale, scale),
 
-                    # This forces a jump at the start of the design and after each trim,
-                    # even if we're close enough not to need one.
-                    "full_jump": True,
-                }
+        # This forces a jump at the start of the design and after each trim,
+        # even if we're close enough not to need one.
+        "full_jump": True,
+    }
 
     pyembroidery.write(pattern, file_path, settings)
diff --git a/lib/simulator.py b/lib/simulator.py
index e662eaf9..530f6ebf 100644
--- a/lib/simulator.py
+++ b/lib/simulator.py
@@ -4,7 +4,7 @@ import time
 from itertools import izip
 
 from .svg import color_block_to_point_lists
-
+from .i18n import _
 
 class EmbroiderySimulator(wx.Frame):
     def __init__(self, *args, **kwargs):
diff --git a/lib/stitch_plan/stitch.py b/lib/stitch_plan/stitch.py
index 5230efec..5fe10fb8 100644
--- a/lib/stitch_plan/stitch.py
+++ b/lib/stitch_plan/stitch.py
@@ -15,15 +15,15 @@ class Stitch(Point):
 
     def __repr__(self):
         return "Stitch(%s, %s, %s, %s, %s, %s, %s, %s%s)" % (self.x,
-                                                       self.y,
-                                                       self.color,
-                                                       "JUMP" if self.jump else " ",
-                                                       "TRIM" if self.trim else " ",
-                                                       "STOP" if self.stop else " ",
-                                                       "NO TIES" if self.no_ties else " ",
-                                                       "FAKE " if self.fake_color_change else "",
-                                                       "COLOR CHANGE" if self.color_change else " "
-                                                      )
+                                                             self.y,
+                                                             self.color,
+                                                             "JUMP" if self.jump else " ",
+                                                             "TRIM" if self.trim else " ",
+                                                             "STOP" if self.stop else " ",
+                                                             "NO TIES" if self.no_ties else " ",
+                                                             "FAKE " if self.fake_color_change else "",
+                                                             "COLOR CHANGE" if self.color_change else " "
+                                                             )
 
     def copy(self):
         return Stitch(self.x, self.y, self.color, self.jump, self.stop, self.trim, self.color_change, self.no_ties)
diff --git a/lib/stitch_plan/stitch_plan.py b/lib/stitch_plan/stitch_plan.py
index 682ea09f..c713b42e 100644
--- a/lib/stitch_plan/stitch_plan.py
+++ b/lib/stitch_plan/stitch_plan.py
@@ -209,8 +209,8 @@ class ColorBlock(object):
                 # Don't consider jumps, stops, color changes, or trims as candidates for filtering
                 pass
             else:
-                l = (stitch - stitches[-1]).length()
-                if l <= 0.1 * PIXELS_PER_MM:
+                length = (stitch - stitches[-1]).length()
+                if length <= 0.1 * PIXELS_PER_MM:
                     # duplicate stitch, skip this one
                     continue
 
diff --git a/lib/stitches/auto_fill.py b/lib/stitches/auto_fill.py
index 097ab1d9..e732c940 100644
--- a/lib/stitches/auto_fill.py
+++ b/lib/stitches/auto_fill.py
@@ -1,20 +1,19 @@
 import sys
 import shapely
 import networkx
-import math
 from itertools import groupby, izip
 from collections import deque
 
 from .fill import intersect_region_with_grating, row_num, stitch_row
 from .running_stitch import running_stitch
 from ..i18n import _
-from ..svg import PIXELS_PER_MM
 from ..utils.geometry import Point as InkstitchPoint, cut
 
 
 class MaxQueueLengthExceeded(Exception):
     pass
 
+
 class PathEdge(object):
     OUTLINE_KEYS = ("outline", "extra", "initial")
     SEGMENT_KEY = "segment"
@@ -39,6 +38,7 @@ class PathEdge(object):
     def is_segment(self):
         return self.key == self.SEGMENT_KEY
 
+
 def auto_fill(shape, angle, row_spacing, end_row_spacing, max_stitch_length, running_stitch_length, staggers, starting_point, ending_point=None):
     stitches = []
 
@@ -65,7 +65,7 @@ def which_outline(shape, coords):
 
     point = shapely.geometry.Point(*coords)
     outlines = enumerate(list(shape.boundary))
-    closest = min(outlines, key=lambda (index, outline): outline.distance(point))
+    closest = min(outlines, key=lambda index_outline: index_outline[1].distance(point))
 
     return closest[0]
 
@@ -129,11 +129,11 @@ def build_graph(shape, segments, angle, row_spacing):
         # Tag each node with its index and projection.
         graph.add_node(node, index=outline_index, projection=outline_projection)
 
-    nodes = list(graph.nodes(data=True)) # returns a list of tuples: [(node, {data}), (node, {data}) ...]
+    nodes = list(graph.nodes(data=True))  # returns a list of tuples: [(node, {data}), (node, {data}) ...]
     nodes.sort(key=lambda node: (node[1]['index'], node[1]['projection']))
 
     for outline_index, nodes in groupby(nodes, key=lambda node: node[1]['index']):
-        nodes = [ node for node, data in nodes ]
+        nodes = [node for node, data in nodes]
 
         # heuristic: change the order I visit the nodes in the outline if necessary.
         # If the start and endpoints are in the same row, I can't tell which row
@@ -163,7 +163,6 @@ def build_graph(shape, segments, angle, row_spacing):
             if i % 2 == edge_set:
                 graph.add_edge(node1, node2, key="extra")
 
-
     if not networkx.is_eulerian(graph):
         raise Exception(_("Unable to autofill.  This most often happens because your shape is made up of multiple sections that aren't connected."))
 
@@ -193,13 +192,13 @@ def bfs_for_loop(graph, starting_node, max_queue_length=2000):
 
         # get a list of neighbors paired with the key of the edge I can follow to get there
         neighbors = [
-                    (node, key)
-                        for node, adj in graph.adj[ending_node].iteritems()
-                        for key in adj
-                ]
+            (node, key)
+            for node, adj in graph.adj[ending_node].iteritems()
+            for key in adj
+        ]
 
         # heuristic: try grating segments first
-        neighbors.sort(key=lambda (dest, key): key == "segment", reverse=True)
+        neighbors.sort(key=lambda dest_key: dest_key[1] == "segment", reverse=True)
 
         for next_node, key in neighbors:
             # skip if I've already followed this edge
@@ -295,6 +294,7 @@ def insert_loop(path, loop):
 
     path[i:i] = loop
 
+
 def nearest_node_on_outline(graph, point, outline_index=0):
     point = shapely.geometry.Point(*point)
     outline_nodes = [node for node, data in graph.nodes(data=True) if data['index'] == outline_index]
@@ -302,16 +302,18 @@ def nearest_node_on_outline(graph, point, outline_index=0):
 
     return nearest
 
+
 def get_outline_nodes(graph, outline_index=0):
-    outline_nodes = [(node, data['projection']) \
-                     for node, data \
-                     in graph.nodes(data=True) \
+    outline_nodes = [(node, data['projection'])
+                     for node, data
+                     in graph.nodes(data=True)
                      if data['index'] == outline_index]
-    outline_nodes.sort(key=lambda (node, projection): projection)
+    outline_nodes.sort(key=lambda node_projection: node_projection[1])
     outline_nodes = [node for node, data in outline_nodes]
 
     return outline_nodes
 
+
 def find_initial_path(graph, starting_point, ending_point=None):
     starting_node = nearest_node_on_outline(graph, starting_point)
 
@@ -340,6 +342,7 @@ def find_initial_path(graph, starting_point, ending_point=None):
 
         return path
 
+
 def find_stitch_path(graph, segments, starting_point=None, ending_point=None):
     """find a path that visits every grating segment exactly once
 
@@ -362,7 +365,6 @@ def find_stitch_path(graph, segments, starting_point=None, ending_point=None):
     the order of most-recently-visited first.
     """
 
-    original_graph = graph
     graph = graph.copy()
     num_segments = len(segments)
     segments_visited = 0
diff --git a/lib/stitches/fill.py b/lib/stitches/fill.py
index 14971cb4..af0a8403 100644
--- a/lib/stitches/fill.py
+++ b/lib/stitches/fill.py
@@ -1,6 +1,5 @@
 import shapely
 import math
-import sys
 
 from ..svg import PIXELS_PER_MM
 from ..utils import cache, Point as InkstitchPoint
@@ -37,6 +36,7 @@ def adjust_stagger(stitch, angle, row_spacing, max_stitch_length, staggers):
 
     return stitch - offset * east(angle)
 
+
 def stitch_row(stitches, beg, end, angle, row_spacing, max_stitch_length, staggers):
     # We want our stitches to look like this:
     #
@@ -119,7 +119,7 @@ def intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing=Non
 
     height = abs(end - start)
 
-    #print >> dbg, "grating:", start, end, height, row_spacing, end_row_spacing
+    # print >> dbg, "grating:", start, end, height, row_spacing, end_row_spacing
 
     # offset start slightly so that rows are always an even multiple of
     # row_spacing_px from the origin.  This makes it so that abutting
@@ -163,11 +163,10 @@ def intersect_region_with_grating(shape, angle, row_spacing, end_row_spacing=Non
 
     return rows
 
+
 def section_to_stitches(group_of_segments, angle, row_spacing, max_stitch_length, staggers):
     stitches = []
-    first_segment = True
     swap = False
-    last_end = None
 
     for segment in group_of_segments:
         (beg, end) = segment
@@ -238,7 +237,7 @@ def pull_runs(rows, shape, row_spacing):
 
         # print >> sys.stderr, len(run)
         runs.append(run)
-        rows = [row for row in rows if len(row) > 0]
+        rows = [r for r in rows if len(r) > 0]
 
         count += 1
 
diff --git a/lib/svg/path.py b/lib/svg/path.py
index 0a8dcb74..4502b2ea 100644
--- a/lib/svg/path.py
+++ b/lib/svg/path.py
@@ -1,8 +1,8 @@
 import simpletransform
-import cubicsuperpath
 
 from .units import get_viewbox_transform
 
+
 def apply_transforms(path, node):
     transform = get_node_transform(node)
 
@@ -11,6 +11,7 @@ def apply_transforms(path, node):
 
     return path
 
+
 def get_node_transform(node):
     # start with the identity transform
     transform = [[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]
@@ -26,6 +27,7 @@ def get_node_transform(node):
 
     return transform
 
+
 def get_correction_transform(node, child=False):
     """Get a transform to apply to new siblings or children of this SVG node"""
 
diff --git a/lib/svg/realistic_rendering.py b/lib/svg/realistic_rendering.py
index e31534da..73da3a09 100644
--- a/lib/svg/realistic_rendering.py
+++ b/lib/svg/realistic_rendering.py
@@ -2,7 +2,7 @@ import simplepath
 import math
 
 from .units import PIXELS_PER_MM
-from ..utils import cache, Point
+from ..utils import Point
 
 # The stitch vector path looks like this:
 #  _______
@@ -102,6 +102,7 @@ realistic_filter = """
     </filter>
 """
 
+
 def realistic_stitch(start, end):
     """Generate a stitch vector path given a start and end point."""
 
diff --git a/lib/svg/svg.py b/lib/svg/svg.py
index 48b1343a..b1cc91d9 100644
--- a/lib/svg/svg.py
+++ b/lib/svg/svg.py
@@ -1,4 +1,6 @@
-import simpletransform, simplestyle, inkex
+import simpletransform
+import simplestyle
+import inkex
 
 from .units import get_viewbox_transform
 from .tags import SVG_GROUP_TAG, INKSCAPE_LABEL, INKSCAPE_GROUPMODE, SVG_PATH_TAG, SVG_DEFS_TAG
@@ -11,13 +13,13 @@ def color_block_to_point_lists(color_block):
     point_lists = [[]]
 
     for stitch in color_block:
-         if stitch.trim:
-              if point_lists[-1]:
-                  point_lists.append([])
-                  continue
+        if stitch.trim:
+            if point_lists[-1]:
+                point_lists.append([])
+                continue
 
-         if not stitch.jump and not stitch.color_change:
-              point_lists[-1].append(stitch.as_tuple())
+        if not stitch.jump and not stitch.color_change:
+            point_lists[-1].append(stitch.as_tuple())
 
     return point_lists
 
@@ -51,13 +53,14 @@ def color_block_to_realistic_stitches(color_block, svg):
                         'stroke': 'none',
                         'filter': 'url(#realistic-stitch-filter)'
                     }),
-                'd': realistic_stitch(start, point),
-                'transform': get_correction_transform(svg)
-                }))
+                 'd': realistic_stitch(start, point),
+                 'transform': get_correction_transform(svg)
+                 }))
             start = point
 
     return paths
 
+
 def color_block_to_paths(color_block, svg):
     paths = []
     # We could emit just a single path with one subpath per point list, but
@@ -68,13 +71,13 @@ def color_block_to_paths(color_block, svg):
             SVG_PATH_TAG,
             {'style': simplestyle.formatStyle(
                 {'stroke': color,
-                'stroke-width': "0.4",
-                'fill': 'none'}),
-            'd': "M" + " ".join(" ".join(str(coord) for coord in point) for point in point_list),
-            'transform': get_correction_transform(svg),
-            'embroider_manual_stitch': 'true',
-            'embroider_trim_after': 'true',
-            }))
+                 'stroke-width': "0.4",
+                 'fill': 'none'}),
+             'd': "M" + " ".join(" ".join(str(coord) for coord in point) for point in point_list),
+             'transform': get_correction_transform(svg),
+             'embroider_manual_stitch': 'true',
+             'embroider_trim_after': 'true',
+             }))
 
     # no need to trim at the end of a thread color
     if paths:
@@ -82,6 +85,7 @@ def color_block_to_paths(color_block, svg):
 
     return paths
 
+
 def render_stitch_plan(svg, stitch_plan, realistic=False):
     layer = svg.find(".//*[@id='__inkstitch_stitch_plan__']")
     if layer is None:
diff --git a/lib/svg/units.py b/lib/svg/units.py
index 126027bc..c4ec82a0 100644
--- a/lib/svg/units.py
+++ b/lib/svg/units.py
@@ -1,13 +1,15 @@
 import simpletransform
 
 from ..utils import cache
+from ..i18n import _
 
 # modern versions of Inkscape use 96 pixels per inch as per the CSS standard
 PIXELS_PER_MM = 96 / 25.4
 
 # cribbed from inkscape-silhouette
-def parse_length_with_units( str ):
 
+
+def parse_length_with_units(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,
@@ -39,8 +41,8 @@ def parse_length_with_units( str ):
         u = '%'
         s = s[:-1]
     try:
-        v = float( s )
-    except:
+        v = float(s)
+    except BaseException:
         raise ValueError(_("parseLengthWithUnits: unknown unit %s") % s)
 
     return v, u
@@ -53,16 +55,16 @@ def convert_length(length):
         return value
 
     if units == 'pt':
-       value /= 72
-       units = 'in'
+        value /= 72
+        units = 'in'
 
     if units == 'pc':
-       value /= 6
-       units = 'in'
+        value /= 6
+        units = 'in'
 
     if units == 'cm':
-       value *= 10
-       units = 'mm'
+        value *= 10
+        units = 'mm'
 
     if units == 'mm':
         value = value / 25.4
@@ -75,6 +77,7 @@ def convert_length(length):
 
     raise ValueError(_("Unknown unit: %s") % units)
 
+
 @cache
 def get_viewbox(svg):
     return svg.get('viewBox').strip().replace(',', ' ').split()
@@ -96,6 +99,7 @@ def get_doc_size(svg):
 
     return doc_width, doc_height
 
+
 @cache
 def get_viewbox_transform(node):
     # somewhat cribbed from inkscape-silhouette
diff --git a/lib/threads/catalog.py b/lib/threads/catalog.py
index d9981dc6..ece2f8ac 100644
--- a/lib/threads/catalog.py
+++ b/lib/threads/catalog.py
@@ -85,8 +85,10 @@ class _ThreadCatalog(Sequence):
             if palette.name == name:
                 return palette
 
+
 _catalog = None
 
+
 def ThreadCatalog():
     """Singleton _ThreadCatalog factory"""
 
diff --git a/lib/threads/color.py b/lib/threads/color.py
index cc6c0c48..8c596e44 100644
--- a/lib/threads/color.py
+++ b/lib/threads/color.py
@@ -3,6 +3,7 @@ import re
 import colorsys
 from pyembroidery.EmbThread import EmbThread
 
+
 class ThreadColor(object):
     hex_str_re = re.compile('#([0-9a-z]{3}|[0-9a-z]{6})', re.I)
 
diff --git a/lib/threads/palette.py b/lib/threads/palette.py
index 785fb082..654c43e5 100644
--- a/lib/threads/palette.py
+++ b/lib/threads/palette.py
@@ -41,8 +41,11 @@ class ThreadPalette(Set):
             if self.name.lower().startswith('name: ink/stitch: '):
                 self.name = self.name[18:]
 
-            columns_line = palette.readline()
-            headers_line = palette.readline()
+            # number of columns
+            palette.readline()
+
+            # headers
+            palette.readline()
 
             for line in palette:
                 fields = line.split("\t", 3)
diff --git a/lib/utils/cache.py b/lib/utils/cache.py
index 38fe8f2c..3a2636f2 100644
--- a/lib/utils/cache.py
+++ b/lib/utils/cache.py
@@ -4,5 +4,7 @@ except ImportError:
     from backports.functools_lru_cache import lru_cache
 
 # simplify use of lru_cache decorator
+
+
 def cache(*args, **kwargs):
     return lru_cache(maxsize=None)(*args, **kwargs)
diff --git a/lib/utils/geometry.py b/lib/utils/geometry.py
index bfdcd3c0..ef5f12b5 100644
--- a/lib/utils/geometry.py
+++ b/lib/utils/geometry.py
@@ -17,7 +17,7 @@ def cut(line, distance):
         last_point = p
         if traveled == distance:
             return [
-                LineString(coords[:i+1]),
+                LineString(coords[:i + 1]),
                 LineString(coords[i:])]
         if traveled > distance:
             cp = line.interpolate(distance)
@@ -25,6 +25,7 @@ def cut(line, distance):
                 LineString(coords[:i] + [(cp.x, cp.y)]),
                 LineString([(cp.x, cp.y)] + coords[i:])]
 
+
 def cut_path(points, length):
     """Return a subsection of at the start of the path that is length units long.
 
@@ -79,7 +80,7 @@ class Point:
         if isinstance(other, (int, float)):
             return self * (1.0 / other)
         else:
-            raise ValueErorr("cannot divide Point by %s" % type(other))
+            raise ValueError("cannot divide Point by %s" % type(other))
 
     def __repr__(self):
         return "Point(%s,%s)" % (self.x, self.y)
diff --git a/lib/utils/inkscape.py b/lib/utils/inkscape.py
index 2d0298bc..a650da69 100644
--- a/lib/utils/inkscape.py
+++ b/lib/utils/inkscape.py
@@ -1,6 +1,7 @@
 from os.path import realpath, expanduser, join as path_join
 import sys
 
+
 def guess_inkscape_config_path():
     if getattr(sys, 'frozen', None):
         path = realpath(path_join(sys._MEIPASS, "..", "..", ".."))
diff --git a/lib/utils/io.py b/lib/utils/io.py
index e5a246f3..f51f629c 100644
--- a/lib/utils/io.py
+++ b/lib/utils/io.py
@@ -19,6 +19,8 @@ def restore_stderr():
 
 # It's probably possible to generalize this code, but when I tried,
 # the result was incredibly unreadable.
+
+
 def save_stdout():
     null = open(os.devnull, 'w')
     sys.stdout_dup = os.dup(sys.stdout.fileno())