refactor everything out of lib/__init__.py

4 files changed, 200 insertions, 0 deletions

diff --git a/lib/svg/__init__.py b/lib/svg/__init__.py
new file mode 100644
index 00000000..1895bba4
--- /dev/null
+++ b/lib/svg/__init__.py
@@ -0,0 +1,2 @@
+from .svg import color_block_to_point_lists, render_stitch_plan
+from .units import *
diff --git a/lib/svg/svg.py b/lib/svg/svg.py
new file mode 100644
index 00000000..3bc546e7
--- /dev/null
+++ b/lib/svg/svg.py
@@ -0,0 +1,81 @@
+import simpletransform, simplestyle, inkex
+
+from .units import get_viewbox_transform
+from .tags import SVG_GROUP_TAG, INKSCAPE_LABEL, INKSCAPE_GROUPMODE, SVG_PATH_TAG
+from ..i18n import _
+from ..utils import cache
+
+
+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 not stitch.jump and not stitch.stop:
+              point_lists[-1].append(stitch.as_tuple())
+
+    return point_lists
+
+
+@cache
+def get_correction_transform(svg):
+    transform = get_viewbox_transform(svg)
+
+    # we need to correct for the viewbox
+    transform = simpletransform.invertTransform(transform)
+    transform = simpletransform.formatTransform(transform)
+
+    return transform
+
+
+def color_block_to_paths(color_block, svg):
+    paths = []
+    # We could emit just a single path with one subpath per point list, but
+    # emitting multiple paths makes it easier for the user to manipulate them.
+    for point_list in color_block_to_point_lists(color_block):
+        color = color_block.color.visible_on_white.to_hex_str()
+        paths.append(inkex.etree.Element(
+            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',
+            }))
+
+    # no need to trim at the end of a thread color
+    if paths:
+        paths[-1].attrib.pop('embroider_trim_after')
+
+    return paths
+
+
+def render_stitch_plan(svg, stitch_plan):
+    layer = svg.find(".//*[@id='__inkstitch_stitch_plan__']")
+    if layer is None:
+        layer = inkex.etree.Element(SVG_GROUP_TAG,
+                                    {'id': '__inkstitch_stitch_plan__',
+                                     INKSCAPE_LABEL: _('Stitch Plan'),
+                                     INKSCAPE_GROUPMODE: 'layer'})
+    else:
+        # delete old stitch plan
+        del layer[:]
+
+        # make sure the layer is visible
+        layer.set('style', 'display:inline')
+
+    for i, color_block in enumerate(stitch_plan):
+        group = inkex.etree.SubElement(layer,
+                                       SVG_GROUP_TAG,
+                                       {'id': '__color_block_%d__' % i,
+                                        INKSCAPE_LABEL: "color block %d" % (i + 1)})
+        group.extend(color_block_to_paths(color_block, svg))
+
+    svg.append(layer)
diff --git a/lib/svg/tags.py b/lib/svg/tags.py
new file mode 100644
index 00000000..fee59957
--- /dev/null
+++ b/lib/svg/tags.py
@@ -0,0 +1,12 @@
+import inkex
+
+
+SVG_PATH_TAG = inkex.addNS('path', 'svg')
+SVG_POLYLINE_TAG = inkex.addNS('polyline', 'svg')
+SVG_DEFS_TAG = inkex.addNS('defs', 'svg')
+SVG_GROUP_TAG = inkex.addNS('g', 'svg')
+
+INKSCAPE_LABEL = inkex.addNS('label', 'inkscape')
+INKSCAPE_GROUPMODE = inkex.addNS('groupmode', 'inkscape')
+
+EMBROIDERABLE_TAGS = (SVG_PATH_TAG, SVG_POLYLINE_TAG)
diff --git a/lib/svg/units.py b/lib/svg/units.py
new file mode 100644
index 00000000..015da60e
--- /dev/null
+++ b/lib/svg/units.py
@@ -0,0 +1,105 @@
+import simpletransform
+
+from ..utils import cache
+
+# 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 ):
+
+    '''
+    Parse an SVG value which may or may not have units attached
+    This version is greatly simplified in that it only allows: no units,
+    units of px, mm, and %.  Everything else, it returns None for.
+    There is a more general routine to consider in scour.py if more
+    generality is ever needed.
+    '''
+
+    u = 'px'
+    s = str.strip()
+    if s[-2:] == 'px':
+        s = s[:-2]
+    elif s[-2:] == 'mm':
+        u = 'mm'
+        s = s[:-2]
+    elif s[-2:] == 'pt':
+        u = 'pt'
+        s = s[:-2]
+    elif s[-2:] == 'pc':
+        u = 'pc'
+        s = s[:-2]
+    elif s[-2:] == 'cm':
+        u = 'cm'
+        s = s[:-2]
+    elif s[-2:] == 'in':
+        u = 'in'
+        s = s[:-2]
+    elif s[-1:] == '%':
+        u = '%'
+        s = s[:-1]
+    try:
+        v = float( s )
+    except:
+        raise ValueError(_("parseLengthWithUnits: unknown unit %s") % s)
+
+    return v, u
+
+
+def convert_length(length):
+    value, units = parse_length_with_units(length)
+
+    if not units or units == "px":
+        return value
+
+    if units == 'pt':
+       value /= 72
+       units = 'in'
+
+    if units == 'pc':
+       value /= 6
+       units = 'in'
+
+    if units == 'cm':
+       value *= 10
+       units = 'mm'
+
+    if units == 'mm':
+        value = value / 25.4
+        units = 'in'
+
+    if units == 'in':
+        # modern versions of Inkscape use CSS's 96 pixels per inch.  When you
+        # open an old document, inkscape will add a viewbox for you.
+        return value * 96
+
+    raise ValueError(_("Unknown unit: %s") % units)
+
+
+@cache
+def get_doc_size(svg):
+    doc_width = convert_length(svg.get('width'))
+    doc_height = convert_length(svg.get('height'))
+
+    return doc_width, doc_height
+
+@cache
+def get_viewbox_transform(node):
+    # somewhat cribbed from inkscape-silhouette
+    doc_width, doc_height = get_doc_size(node)
+
+    viewbox = node.get('viewBox').strip().replace(',', ' ').split()
+
+    dx = -float(viewbox[0])
+    dy = -float(viewbox[1])
+    transform = simpletransform.parseTransform("translate(%f, %f)" % (dx, dy))
+
+    try:
+        sx = doc_width / float(viewbox[2])
+        sy = doc_height / float(viewbox[3])
+        scale_transform = simpletransform.parseTransform("scale(%f, %f)" % (sx, sy))
+        transform = simpletransform.composeTransform(transform, scale_transform)
+    except ZeroDivisionError:
+        pass
+
+    return transform