Convert to satin internally (3874)

3 files changed, 50 insertions, 4 deletions

diff --git a/lib/svg/__init__.py b/lib/svg/__init__.py
index b17a37f0..6694d534 100644
--- a/lib/svg/__init__.py
+++ b/lib/svg/__init__.py
@@ -4,8 +4,10 @@
 # Licensed under the GNU GPL version 3.0 or later.  See the file LICENSE for details.
 
 from .guides import get_guides
-from .path import apply_transforms, get_node_transform, get_correction_transform, line_strings_to_csp, point_lists_to_csp, line_strings_to_path
-from .path import apply_transforms, get_node_transform, get_correction_transform, line_strings_to_csp, point_lists_to_csp
+from .path import (apply_transforms, get_correction_transform,
+                   get_node_transform, line_strings_to_coordinate_lists,
+                   line_strings_to_csp, line_strings_to_path,
+                   point_lists_to_csp)
 from .rendering import color_block_to_point_lists, render_stitch_plan
-from .svg import get_document, generate_unique_id
-from .units import *
\ No newline at end of file
+from .svg import generate_unique_id, get_document
+from .units import *
diff --git a/lib/svg/path.py b/lib/svg/path.py
index 5e6e7007..a7c7b1ca 100644
--- a/lib/svg/path.py
+++ b/lib/svg/path.py
@@ -85,6 +85,19 @@ def get_correction_transform(node: inkex.BaseElement, child=False) -> str:
     return str(transform)
 
 
+def line_strings_to_coordinate_lists(line_strings):
+    try:
+        # This lets us accept a MultiLineString or a list.
+        line_strings = line_strings.geoms
+    except AttributeError:
+        pass
+
+    if line_strings is None:
+        return None
+
+    return [list(ls.coords) for ls in line_strings]
+
+
 def line_strings_to_csp(line_strings):
     try:
         # This lets us accept a MultiLineString or a list.
diff --git a/lib/svg/styles.py b/lib/svg/styles.py
new file mode 100644
index 00000000..c3daaf19
--- /dev/null
+++ b/lib/svg/styles.py
@@ -0,0 +1,31 @@
+# Authors: see git history
+#
+# Copyright (c) 2025 Authors
+# Licensed under the GNU GPL version 3.0 or later.  See the file LICENSE for details.
+
+from shapely.geometry import JOIN_STYLE
+
+
+def get_join_style_args(element):
+    """Convert svg line join style to shapely offset_curve arguments."""
+
+    args = {
+        # mitre is the default per SVG spec
+        'join_style': JOIN_STYLE.mitre
+    }
+
+    element_join_style = element.get_style('stroke-linejoin')
+
+    if element_join_style is not None:
+        if element_join_style == "miter":
+            args['join_style'] = JOIN_STYLE.mitre
+
+            # 4 is the default per SVG spec
+            miter_limit = float(element.get_style('stroke-miterlimit', 4))
+            args['mitre_limit'] = miter_limit
+        elif element_join_style == "bevel":
+            args['join_style'] = JOIN_STYLE.bevel
+        elif element_join_style == "round":
+            args['join_style'] = JOIN_STYLE.round
+
+    return args