add realistic boolean param to render_stitch_plan()

2 files changed, 171 insertions, 124 deletions

diff --git a/lib/svg/realistic_rendering.py b/lib/svg/realistic_rendering.py
new file mode 100644
index 00000000..e31534da
--- /dev/null
+++ b/lib/svg/realistic_rendering.py
@@ -0,0 +1,129 @@
+import simplepath
+import math
+
+from .units import PIXELS_PER_MM
+from ..utils import cache, Point
+
+# The stitch vector path looks like this:
+#  _______
+# (_______)
+#
+# It's 0.32mm high, which is the approximate thickness of common machine
+# embroidery threads.
+
+# 1.216 pixels = 0.32mm
+stitch_height = 1.216
+
+# This vector path starts at the upper right corner of the stitch shape and
+# proceeds counter-clockwise.and contains a placeholder (%s) for the stitch
+# length.
+#
+# It contains two invisible "whiskers" of zero width that go above and below
+# to ensure that the SVG renderer allocates a large enough canvas area when
+# computing the gaussian blur steps.  Otherwise, we'd have to expand the
+# width and height attributes of the <filter> tag to add more buffer space.
+# The width and height are specified in multiples of the bounding box
+# size, It's the bounding box aligned with the global SVG canvas's axes, not
+# the axes of the stitch itself.  That means that having a big enough value
+# to add enough padding on the long sides of the stitch would waste a ton
+# of space on the short sides and significantly slow down rendering.
+stitch_path = "M0,0c0.4,0,0.4,0.3,0.4,0.6c0,0.3,-0.1,0.6,-0.4,0.6v0.2,-0.2h-%sc-0.4,0,-0.4,-0.3,-0.4,-0.6c0,-0.3,0.1,-0.6,0.4,-0.6v-0.2,0.2z"
+
+# This filter makes the above stitch path look like a real stitch with lighting.
+realistic_filter = """
+    <filter
+       style="color-interpolation-filters:sRGB"
+       id="realistic-stitch-filter"
+       x="-0.1"
+       width="1.2"
+       y="-0.1"
+       height="1.2">
+      <feGaussianBlur
+         stdDeviation="1.5"
+         id="feGaussianBlur1542-6"
+         in="SourceAlpha" />
+      <feComponentTransfer
+         id="feComponentTransfer1544-7"
+         result="result1">
+        <feFuncR
+           id="feFuncR1546-5"
+           type="identity" />
+        <feFuncG
+           id="feFuncG1548-3"
+           type="identity" />
+        <feFuncB
+           id="feFuncB1550-5"
+           type="identity"
+           slope="4.5300000000000002" />
+        <feFuncA
+           id="feFuncA1552-6"
+           type="gamma"
+           slope="0.14999999999999999"
+           intercept="0"
+           amplitude="3.1299999999999999"
+           offset="-0.33000000000000002" />
+      </feComponentTransfer>
+      <feComposite
+         in2="SourceAlpha"
+         id="feComposite1558-2"
+         operator="in" />
+      <feGaussianBlur
+         stdDeviation="0.089999999999999997"
+         id="feGaussianBlur1969" />
+      <feMorphology
+         id="feMorphology1971"
+         operator="dilate"
+         radius="0.10000000000000001" />
+      <feSpecularLighting
+         id="feSpecularLighting1973"
+         result="result2"
+         specularConstant="0.70899999"
+         surfaceScale="30">
+        <fePointLight
+           id="fePointLight1975"
+           z="10" />
+      </feSpecularLighting>
+      <feGaussianBlur
+         stdDeviation="0.040000000000000001"
+         id="feGaussianBlur1979" />
+      <feComposite
+         in2="SourceGraphic"
+         id="feComposite1977"
+         operator="arithmetic"
+         k2="1"
+         k3="1"
+         result="result3"
+         k1="0"
+         k4="0" />
+      <feComposite
+         in2="SourceAlpha"
+         id="feComposite1981"
+         operator="in" />
+    </filter>
+"""
+
+def realistic_stitch(start, end):
+    """Generate a stitch vector path given a start and end point."""
+
+    end = Point(*end)
+    start = Point(*start)
+
+    stitch_length = (end - start).length()
+    stitch_center = (end + start) / 2.0
+    stitch_direction = (end - start)
+    stitch_angle = math.atan2(stitch_direction.y, stitch_direction.x)
+
+    stitch_length = max(0, stitch_length - 0.2 * PIXELS_PER_MM)
+
+    # create the path by filling in the length in the template
+    path = simplepath.parsePath(stitch_path % stitch_length)
+
+    # rotate the path to match the stitch
+    rotation_center_x = -stitch_length / 2.0
+    rotation_center_y = stitch_height / 2.0
+    simplepath.rotatePath(path, stitch_angle, cx=rotation_center_x, cy=rotation_center_y)
+
+    # move the path to the location of the stitch
+    simplepath.translatePath(path, stitch_center.x - rotation_center_x, stitch_center.y - rotation_center_y)
+
+    return simplepath.formatPath(path)
diff --git a/lib/svg/svg.py b/lib/svg/svg.py
index 655ddc58..5552abd8 100644
--- a/lib/svg/svg.py
+++ b/lib/svg/svg.py
@@ -1,122 +1,10 @@
-import math
-import simpletransform, simplestyle, simplepath, inkex
+import simpletransform, simplestyle, inkex
 
-from .units import get_viewbox_transform, PIXELS_PER_MM
+from .units import get_viewbox_transform
 from .tags import SVG_GROUP_TAG, INKSCAPE_LABEL, INKSCAPE_GROUPMODE, SVG_PATH_TAG, SVG_DEFS_TAG
+from .realistic_rendering import realistic_stitch, realistic_filter
 from ..i18n import _
-from ..utils import cache, Point
-
-
-# The stitch vector path looks like this:
-#  _______
-# (_______)
-#
-# It's 0.32mm high, which is the approximate thickness of common machine embroidery threads.
-
-# 1.216 pixels = 0.32mm
-stitch_height = 1.216
-
-# This vector path starts at the origin and contains a placeholder (%s) for the stitch length.
-stitch_path = "M0,0c0.4,0,0.4,0.3,0.4,0.6c0,0.3,-0.1,0.6,-0.4,0.6v0.2,-0.2h-%sc-0.4,0,-0.4,-0.3,-0.4,-0.6c0,-0.3,0.1,-0.6,0.4,-0.6v-0.2,0.2z"
-
-# This filter makes the above stitch path look like a real stitch with lighting.
-realistic_filter = """
-    <filter
-       style="color-interpolation-filters:sRGB"
-       id="realistic-stitch-filter"
-       x="-0.1"
-       width="1.2"
-       y="-0.1"
-       height="1.2">
-      <feGaussianBlur
-         stdDeviation="1.5"
-         id="feGaussianBlur1542-6"
-         in="SourceAlpha" />
-      <feComponentTransfer
-         id="feComponentTransfer1544-7"
-         result="result1">
-        <feFuncR
-           id="feFuncR1546-5"
-           type="identity" />
-        <feFuncG
-           id="feFuncG1548-3"
-           type="identity" />
-        <feFuncB
-           id="feFuncB1550-5"
-           type="identity"
-           slope="4.5300000000000002" />
-        <feFuncA
-           id="feFuncA1552-6"
-           type="gamma"
-           slope="0.14999999999999999"
-           intercept="0"
-           amplitude="3.1299999999999999"
-           offset="-0.33000000000000002" />
-      </feComponentTransfer>
-      <feComposite
-         in2="SourceAlpha"
-         id="feComposite1558-2"
-         operator="in" />
-      <feGaussianBlur
-         stdDeviation="0.089999999999999997"
-         id="feGaussianBlur1969" />
-      <feMorphology
-         id="feMorphology1971"
-         operator="dilate"
-         radius="0.10000000000000001" />
-      <feSpecularLighting
-         id="feSpecularLighting1973"
-         result="result2"
-         specularConstant="0.70899999"
-         surfaceScale="30">
-        <fePointLight
-           id="fePointLight1975"
-           z="10" />
-      </feSpecularLighting>
-      <feGaussianBlur
-         stdDeviation="0.040000000000000001"
-         id="feGaussianBlur1979" />
-      <feComposite
-         in2="SourceGraphic"
-         id="feComposite1977"
-         operator="arithmetic"
-         k2="1"
-         k3="1"
-         result="result3"
-         k1="0"
-         k4="0" />
-      <feComposite
-         in2="SourceAlpha"
-         id="feComposite1981"
-         operator="in" />
-    </filter>
-"""
-
-def realistic_stitch(start, end):
-    """Generate a stitch vector path given a start and end point."""
-
-    end = Point(*end)
-    start = Point(*start)
-
-    stitch_length = (end - start).length()
-    stitch_center = (end + start) / 2.0
-    stitch_direction = (end - start)
-    stitch_angle = math.atan2(stitch_direction.y, stitch_direction.x)
-
-    stitch_length = max(0, stitch_length - 0.2 * PIXELS_PER_MM)
-
-    # create the path by filling in the length in the template
-    path = simplepath.parsePath(stitch_path % stitch_length)
-
-    # rotate the path to match the stitch
-    rotation_center_x = -stitch_length / 2.0
-    rotation_center_y = stitch_height / 2.0
-    simplepath.rotatePath(path, stitch_angle, cx=rotation_center_x, cy=rotation_center_y)
-
-    # move the path to the location of the stitch
-    simplepath.translatePath(path, stitch_center.x - rotation_center_x, stitch_center.y - rotation_center_y)
-
-    return simplepath.formatPath(path)
+from ..utils import cache
 
 
 def color_block_to_point_lists(color_block):
@@ -145,10 +33,9 @@ def get_correction_transform(svg):
     return transform
 
 
-def color_block_to_paths(color_block, svg):
+def color_block_to_realistic_stitches(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.darker.to_hex_str()
         start = point_list[0]
@@ -168,8 +55,31 @@ def color_block_to_paths(color_block, svg):
 
     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
+    # 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):
+def render_stitch_plan(svg, stitch_plan, realistic=False):
     layer = svg.find(".//*[@id='__inkstitch_stitch_plan__']")
     if layer is None:
         layer = inkex.etree.Element(SVG_GROUP_TAG,
@@ -188,9 +98,17 @@ def render_stitch_plan(svg, stitch_plan):
                                        SVG_GROUP_TAG,
                                        {'id': '__color_block_%d__' % i,
                                         INKSCAPE_LABEL: "color block %d" % (i + 1)})
-        group.extend(color_block_to_paths(color_block, svg))
-
-    defs = svg.find(SVG_DEFS_TAG)
-    defs.append(inkex.etree.fromstring(realistic_filter))
+        if realistic:
+            group.extend(color_block_to_realistic_stitches(color_block, svg))
+        else:
+            group.extend(color_block_to_paths(color_block, svg))
 
     svg.append(layer)
+
+    if realistic:
+        defs = svg.find(SVG_DEFS_TAG)
+
+        if defs is None:
+            defs = inkex.etree.SubElement(svg, SVG_DEFS_TAG)
+
+        defs.append(inkex.etree.fromstring(realistic_filter))