add a smoothing enum explicitly for FBX export and make sure other formats were exporting smoothing data correctly on export

Author: speculative-artefact

operators.py

@@ -700,6 +700,7 @@ def export_object(obj, file_path, scene_props):
                     object_types={"MESH"},
                     path_mode="COPY",
                     embed_textures=True,
+                    mesh_smooth_type=scene_props.mesh_export_smoothing,
                     use_mesh_modifiers=False, # Handled by apply_mesh_modifiers
                     use_triangles=False,      # Handled by triangulate_mesh
                 )
@@ -712,6 +713,8 @@ def export_object(obj, file_path, scene_props):
                     up_axis=scene_props.mesh_export_coord_up,
                     export_materials=True,
                     path_mode="COPY",
+                    export_normals=True,
+                    export_smooth_groups=True,
                     apply_modifiers=False, # Handled by apply_mesh_modifiers
                     export_triangulated_mesh=False, # Handled triangulate_mesh
                 )
@@ -722,6 +725,7 @@ def export_object(obj, file_path, scene_props):
                     export_format="GLTF_SEPARATE", # or GLB
                     export_apply=False, # Transforms/Mods applied manually
                     export_attributes=True,
+                    export_normals=True,
                     export_extras=True,
                     export_yup=(scene_props.mesh_export_coord_up == "Y"),
                     # Need to add a prop to track material quality
@@ -738,6 +742,7 @@ def export_object(obj, file_path, scene_props):
                         scene_props.mesh_export_coord_up),
                     export_meshes=True,
                     export_materials=True,
+                    export_normals=True,
                     generate_preview_surface=False,
                     use_instancing=False,
                     evaluation_mode="RENDER",
@@ -752,6 +757,7 @@ def export_object(obj, file_path, scene_props):
                 bpy.ops.wm.stl_export(
                     filepath=export_filepath,
                     export_selected_objects=True,
+                    use_selection=True,
                     global_scale=1.0, # Scale applied setup_export_object
                     forward_axis=scene_props.mesh_export_coord_forward,
                     up_axis=scene_props.mesh_export_coord_up,

panels.py

@@ -35,6 +35,10 @@ def format_has_scale(self, format):
     def format_has_coordinates(self, format):
         """Check if the format is compatible with coordinate export settings"""
         return format in {"FBX", "OBJ", "USD", "STL"}
+    
+    def format_has_smoothing(self, format):
+        """Check if the format is compatible with smoothing export settings"""
+        return format in {"FBX"}
 
 
     def draw(self, context):
@@ -88,6 +92,13 @@ def draw(self, context):
         row = col.row(align=True)
         row.prop(settings, "mesh_export_units", expand=True)
 
+        # Smoothing settings
+        if self.format_has_smoothing(settings.mesh_export_format):
+            # Only show if the format supports smoothing
+            col = layout.column(heading="Smoothing", align=True)
+            row = col.row(align=True)
+            row.prop(settings, "mesh_export_smoothing", expand=True)
+
         # Zero location settings
         col = layout.column(align=True)
         col.prop(settings, "mesh_export_zero_location")

properties.py

@@ -80,6 +80,18 @@ class MeshExporterSettings(PropertyGroup):
         default="X"
     )
 
+    mesh_export_smoothing: EnumProperty(
+        name="Smoothing",
+        description="Smoothing method for exported meshes",
+        items=[
+            ("OFF", "Off", "Export only normals instead "
+            "of writing edge or face smoothing data"),
+            ("FACE", "Face", "Write face smoothing"),
+            ("EDGE", "Edge", "Write edge smoothing"),
+        ],
+        default="FACE"
+    )
+
     # Zero location property
     mesh_export_zero_location: BoolProperty(
         name="Zero Location",