feat(cutout): implement boundary padding for cutout textures

- Introduced a new `Boundary Padding` preference in the Cutout Tool with a default of 2 px and a configurable range of 1-4 px.
- Updated the Cutout client to establish inward mapping from the final Mask, sampling in a fixed direction and processing independent material RGBA and Depth.
- Enhanced the handling of RGBA and Depth during cutout operations, ensuring proper mapping and preservation of source data.
- Added tests to validate the new boundary padding functionality and its integration with existing cutout processes.

feat(geometry): remove overall mesh smoothing from geometry nodes

- Removed the `Smooth` input from several geometry node groups to eliminate unnecessary overall mesh smoothing.
- Retained `Smooth Weight` for depth nodes while removing it from Cutout and Relief Plane nodes.
- Ensured that boundary, normal, and fill smoothing behaviors remain intact and consistent.
- Updated tests and documentation to reflect the changes in node interfaces and behaviors.

feat(normals): scale tangent normals with depth

- Reused the existing `o_normal_reduction` attribute to adjust Tangent Normal strength based on the geometry's `Depth Scale`.
- Ensured that Tangent Normal strength is consistent with the geometry depth, preserving full strength for materials that do not provide the attribute.
- Updated tests to verify the correct behavior of normal strength adjustments in both Tangent and Object Space.

tools/nodes/groups/image_depth_cutout.py

@@ -3,7 +3,6 @@ import bpy
 from mathutils import Matrix
 from anyimage.operators.cutout_tool.shape import CUTOUT_Z_TO_X, NORMAL_REDUCTION_ATTRIBUTE_NAME
 from ..common.nodes import interface_socket, group_input, math_node, float_input, menu_switch, read_float_attribute, store_float_attribute, prepare_node_group, sample_field, evaluate_field
-from ..common.smoothing import expand_smooth
 from ..common.boundary_smoothing import smooth_cut_boundary
 from ..common.cutout import _island_cleanup, _position_field, _remove_zero_thickness, _shade_output
 from ..common.depth_surface import _math, project_depth_surface, build_surface_camera, split_depth_surface, sample_face_camera, thicken_depth_surface
@@ -341,17 +340,13 @@ def build_image_depth_cutout_group():
     group.color_tag = 'GEOMETRY'
     interface_socket(group, 'Geometry', 'INPUT', 'NodeSocketGeometry')
     interface_socket(group, 'Mode', 'INPUT', 'NodeSocketMenu')
-    float_input(group, 'Thickness', 0.0).description = 'Control how much the surface bulges in Balloon mode. Zero removes the bulge.'
-    float_input(group, 'Shell Thickness', 0.0, subtype='DISTANCE').description = 'Add thickness behind the original surface while keeping the front surface in place.'
-    float_input(group, 'Depth Scale', 1.0)
+    float_input(group, 'Thickness', 0.0, maximum=2.0).description = 'Control how much the surface bulges in Balloon mode. Zero removes the bulge.'
+    float_input(group, 'Shell Thickness', 0.0, maximum=1.0, subtype='DISTANCE').description = 'Add thickness behind the original surface while keeping the front surface in place.'
+    float_input(group, 'Depth Scale', 1.0, maximum=2.0)
     float_input(group, 'Depth Split', 0.1, maximum=1, subtype='FACTOR').description = 'Split the mesh where depth changes abruptly. Higher values detect smaller depth jumps. Zero disables splitting.'
-    iterations = interface_socket(group, 'Smooth', 'INPUT', 'NodeSocketInt')
-    iterations.description = 'Set the number of mesh smoothing passes. Higher values smooth the surface more but may soften details. Zero disables smoothing.'
-    iterations.default_value = 0
-    iterations.min_value, iterations.max_value = (0, 20)
     options = group.interface.new_panel(name='Options', default_closed=True)
     float_input(group, 'Cleanup Threshold', 0.0, parent=options)
-    float_input(group, 'Smooth Weight', 1.0, maximum=1, subtype='FACTOR', parent=options).description = 'Control the strength of each mesh smoothing pass. Higher values move vertices more.'
+    float_input(group, 'Smooth Weight', 1.0, maximum=1, subtype='FACTOR', parent=options).description = 'Control the strength of boundary smoothing. Higher values move boundary vertices more.'
     float_input(group, 'Reference Depth', 1.0, subtype='DISTANCE', parent=options)
     interface_socket(group, 'Depth Axis', 'INPUT', 'NodeSocketMenu', options).menu_expanded = True
     boundary_smooth = interface_socket(group, 'Boundary Smooth', 'INPUT', 'NodeSocketInt', options)
@@ -373,7 +368,6 @@ def build_image_depth_cutout_group():
     cleaned = store_float_attribute(group, cleaned, NORMAL_REDUCTION_ATTRIBUTE_NAME, 0.0, domain='FACE')
     controls = group_input(group.nodes, set())
     geometry = _build_depth_surface(group, cleaned, controls)
-    geometry = expand_smooth(group, geometry, iterations_name='Smooth', weight_name='Smooth Weight')
     orient = group.nodes.new('GeometryNodeTransform')
     orient.inputs['Rotation'].default_value = Matrix(CUTOUT_Z_TO_X).to_euler()
     group.links.new(geometry, orient.inputs['Geometry'])