feat: Implement weight cutout boundary smoothing for image depth cutout

- Added a new proposal for boundary smoothing in the weight cutout process, differentiating between Split edges and Outline smoothing requirements.
- Introduced a new capability `cutout-boundary-smoothing` to control smoothing strength and default values.
- Updated specifications to define the behavior of boundary-specific smoothing strength and default settings.
- Created tasks to verify the implementation of boundary behavior and asset updates.
- Developed comprehensive tests for depth symmetry and normal scaling to ensure expected behavior and performance.
- Introduced new attributes for normal mapping to facilitate persistent face attributes sharing between depth symmetry and image materials.
- Built a new node group for O Image Depth Symmetry, integrating the new smoothing capabilities and ensuring compatibility with existing workflows.

tools/nodes/common/boundary_smoothing.py

@@ -5,10 +5,12 @@ from .depth_surface import _math
 from .smoothing import edge_boundary_field, expand_smooth
 
 
-def boundary_influence(group, protected=False):
+def boundary_influence(group, protected=False, *, boundary=None):
     """Fade a boundary field through two rings while excluding protected points."""
     nodes, links = group.nodes, group.links
-    boundary = evaluate_field(group, edge_boundary_field(nodes, links), "FLOAT", "POINT")
+    if boundary is None:
+        boundary = edge_boundary_field(nodes, links)
+    boundary = evaluate_field(group, boundary, "FLOAT", "POINT")
     unprotected = _math(group, "SUBTRACT", 1, protected)
     cut = _math(group, "MULTIPLY", boundary, unprotected)
     blur = nodes.new("GeometryNodeBlurAttribute")
@@ -75,9 +77,20 @@ def reconstruct_camera_depth(group, camera, depth, smoothed):
     return choose.outputs[0]
 
 
-def smooth_cut_boundary(group, geometry, original_boundary=False):
-    """Blend O Smooth's pinned-boundary result through a two-ring edge mask."""
-    influence = boundary_influence(group, original_boundary)
+def cut_boundary_influence(group, split_boundary):
+    """Give split edges full influence and the original outline one tenth."""
+    nodes, links = group.nodes, group.links
+    boundary = evaluate_field(group, edge_boundary_field(nodes, links), "FLOAT", "POINT")
+    split = _math(group, "MULTIPLY", boundary, split_boundary)
+    outline = _math(group, "MAXIMUM", _math(group, "SUBTRACT", boundary, split), 0)
+    split_influence = boundary_influence(group, boundary=split)
+    outline_influence = _math(group, "MULTIPLY", boundary_influence(group, boundary=outline), 0.1)
+    return _math(group, "MAXIMUM", split_influence, outline_influence)
+
+
+def smooth_cut_boundary(group, geometry, split_boundary=False):
+    """Blend O Smooth through split and outline masks with distinct weights."""
+    influence = cut_boundary_influence(group, split_boundary)
     # The support band depends on topology, which stays unchanged in the loop.
     return expand_smooth(
         group, geometry, iterations_name="Boundary Smooth", weight_name="Smooth Weight",