1 files changed, 131 insertions, 0 deletions
diff --git a/lib/output.py b/lib/output.py
new file mode 100644
index 00000000..b94d7387
--- /dev/null
+++ b/lib/output.py
@@ -0,0 +1,131 @@
+import libembroidery
+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
+
+
+def make_thread(color):
+    thread = libembroidery.EmbThread()
+    thread.color = libembroidery.embColor_make(*color.rgb)
+
+    thread.description = color.name
+    thread.catalogNumber = ""
+
+    return thread
+
+def add_thread(pattern, thread):
+    """Add a thread to a pattern and return the thread's index"""
+
+    libembroidery.embPattern_addThread(pattern, thread)
+
+    return libembroidery.embThreadList_count(pattern.threadList) - 1
+
+def get_flags(stitch):
+    flags = 0
+
+    if stitch.jump:
+        flags |= libembroidery.JUMP
+
+    if stitch.trim:
+        flags |= libembroidery.TRIM
+
+    if stitch.stop:
+        flags |= libembroidery.STOP
+
+    return flags
+
+
+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.
+
+    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")]
+
+    # document size used below
+    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)
+
+    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 write_embroidery_file(file_path, stitch_plan, svg):
+    origin = get_origin(svg)
+
+    pattern = libembroidery.embPattern_create()
+
+    for color_block in stitch_plan:
+        add_thread(pattern, make_thread(color_block.color))
+
+        for stitch in color_block:
+            if stitch.stop and stitch is not color_block.last_stitch:
+                # A STOP stitch that is not at the end of a color block
+                # occurs when the user specified "STOP after".  "STOP" is the
+                # same thing as a color change, and the user will assign a
+                # special color at the machine that tells it to pause after.
+                # We need to add another copy of the same color here so that
+                # the stitches after the STOP are still the same color.
+                add_thread(pattern, make_thread(color_block.color))
+
+            flags = get_flags(stitch)
+            libembroidery.embPattern_addStitchAbs(pattern, stitch.x - origin.x, stitch.y - origin.y, flags, 1)
+
+    libembroidery.embPattern_addStitchAbs(pattern, stitch.x - origin.x, stitch.y - origin.y, libembroidery.END, 1)
+
+    # convert from pixels to millimeters
+    libembroidery.embPattern_scale(pattern, 1/PIXELS_PER_MM)
+
+    # SVG and embroidery disagree on the direction of the Y axis
+    libembroidery.embPattern_flipVertical(pattern)
+
+    libembroidery.embPattern_write(pattern, file_path)