Implement Balloon Depth Sampling and Validation Tools

- Added depth.py for MoGe-2 depth sampling and balloon deformation functionality.
- Introduced validate_balloon_asset.py to validate balloon shape modifiers and material properties in Blender.
- Enhanced test_server.py with new unit tests for balloon depth analysis and job progress tracking.
- Updated existing tests to improve code clarity and maintainability.

tools/validate_balloon_asset.py

@@ -0,0 +1,136 @@
+from pathlib import Path
+import sys
+
+import bpy
+
+
+PROJECT_ROOT = Path(__file__).parents[1]
+sys.path.insert(0, str(PROJECT_ROOT / "src"))
+sys.path.insert(
+    0,
+    str(next((PROJECT_ROOT / "src" / "snapform" / "wheels").glob("blendjob-*.whl"))),
+)
+
+from snapform.operators.balloon.depth import (
+    BALLOON_DEPTH_ATTRIBUTE,
+    add_balloon_shape_modifier,
+    balloon_shape_node_group,
+)
+from snapform.operators.balloon.operator import (
+    mark_balloon_material,
+    merge_balloon_normal_image,
+    reusable_balloon_material,
+)
+from snapform.operators.material import (
+    BALLOON_MATERIAL_NODE_GROUP_NAME,
+    material_node_group,
+    set_modifier_input,
+)
+
+
+def input_socket(group, name):
+    return next(
+        item
+        for item in group.interface.items_tree
+        if item.item_type == "SOCKET"
+        and item.in_out == "INPUT"
+        and item.name == name
+    )
+
+
+def main():
+    bpy.ops.wm.read_factory_settings(use_empty=True)
+    group = balloon_shape_node_group()
+    assert group.is_modifier
+    assert input_socket(group, "Double Sided Depth").default_value is False
+    smoother = next(
+        node
+        for node in group.nodes
+        if node.bl_idname == "ShaderNodeMapRange"
+        and node.interpolation_type == "SMOOTHERSTEP"
+    )
+    assert smoother.clamp
+    assert not any(
+        node.bl_idname == "ShaderNodeMath"
+        and node.operation == "MAXIMUM"
+        and node.label == "Clamp Depth"
+        for node in group.nodes
+    )
+
+    mesh = bpy.data.meshes.new("Balloon Validation Mesh")
+    mesh.from_pydata(
+        (
+            (-1.0, 0.0, 0.0),
+            (-0.5, 0.0, 0.0),
+            (0.0, 0.0, 0.0),
+            (1.0, 0.0, 0.0),
+        ),
+        (),
+        (),
+    )
+    depth = mesh.attributes.new(BALLOON_DEPTH_ATTRIBUTE, "FLOAT", "POINT")
+    depth.data.foreach_set("value", (0.0, 2.0, 2.0, 2.0))
+    obj = bpy.data.objects.new("Balloon Validation", mesh)
+    bpy.context.scene.collection.objects.link(obj)
+    modifier = add_balloon_shape_modifier(obj, 1.0)
+    evaluated = obj.evaluated_get(bpy.context.evaluated_depsgraph_get())
+    result = evaluated.to_mesh()
+    try:
+        x = [vertex.co.x for vertex in result.vertices]
+        assert abs(x[0] + 1.0) < 1e-5
+        assert abs(x[1] + 1.25) < 1e-5
+        assert abs(x[2]) < 1e-5
+        assert abs(x[3] - 1.0) < 1e-5
+    finally:
+        evaluated.to_mesh_clear()
+
+    set_modifier_input(modifier, input_socket(group, "Thickness").identifier, 2.0)
+    obj.update_tag(refresh={"DATA"})
+    bpy.context.view_layer.update()
+    evaluated = obj.evaluated_get(bpy.context.evaluated_depsgraph_get())
+    result = evaluated.to_mesh()
+    try:
+        x = [vertex.co.x for vertex in result.vertices]
+        assert abs(x[0] + 1.0) < 1e-5
+        assert abs(x[3] - 2.0) < 1e-5
+    finally:
+        evaluated.to_mesh_clear()
+
+    material_group = material_node_group(
+        surface_group_name=BALLOON_MATERIAL_NODE_GROUP_NAME,
+    )
+    normal_map = next(
+        node
+        for node in material_group.nodes
+        if node.bl_idname == "ShaderNodeNormalMap"
+    )
+    assert normal_map.space == "TANGENT"
+    assert abs(input_socket(material_group, "Normal Strength").default_value - 0.5) < 1e-6
+
+    source_image = bpy.data.images.new("Reuse Source", 2, 1)
+    shared_normal = bpy.data.images.new("Shared Normal", 2, 1)
+    shared_normal.pixels.foreach_set(
+        (128 / 255, 128 / 255, 1, 1, 128 / 255, 128 / 255, 1, 1)
+    )
+    material = bpy.data.materials.new("Unrelated Material Name")
+    mark_balloon_material(material, source_image, shared_normal)
+    assert reusable_balloon_material(
+        "unused",
+        "unused",
+        source_image,
+        normal_required=True,
+    ) is material
+
+    update_normal = bpy.data.images.new("Normal Update", 2, 1)
+    update_normal.pixels.foreach_set(
+        (1, 0.25, 0.75, 1, 128 / 255, 128 / 255, 1, 1)
+    )
+    merge_balloon_normal_image(shared_normal, update_normal)
+    pixels = list(shared_normal.pixels)
+    assert abs(pixels[0] - 1.0) < 1e-5
+    assert abs(pixels[4] - 128 / 255) < 1e-5
+    print(f"Validated Blender {bpy.app.version_string}: {group.name}")
+
+
+if __name__ == "__main__":
+    main()