将 Xynova 笔画延长至 50% 黑色覆盖率

沿现有笔画向空白处增长，保留最小线宽和笔画间隙。41 项测试通过，双 UV 矢量图无重叠。

blender/scripts/stroke_geometry.py

@@ -36,10 +36,12 @@ def capsule_segment(cx, cy, half_length, angle):
     return (cx - dx, cy - dy), (cx + dx, cy + dy)
 
 
-def has_clearance(candidate, accepted, clearance):
+def has_clearance(candidate, accepted, clearance, skip_index=None):
     """Capsules are (start, end, radius), all in the same physical units."""
     start, end, radius = candidate
-    for other_start, other_end, other_radius in accepted:
+    for index, (other_start, other_end, other_radius) in enumerate(accepted):
+        if index == skip_index:
+            continue
         limit = radius + other_radius + clearance
         if (max(start[0], end[0]) + limit < min(other_start[0], other_end[0])
                 or max(other_start[0], other_end[0]) + limit < min(start[0], end[0])