New feature to calculate area of selected faces

src/ifcblenderexport/blenderbim/bim/__init__.py

@@ -170,6 +170,7 @@ if bpy is not None:
         operator.SelectIfcPatchOutput,
         operator.ExecuteIfcPatch,
         operator.CalculateEdgeLengths,
+        operator.CalculateFaceAreas,
         prop.StrProperty,
         prop.Variable,
         prop.Role,

src/ifcblenderexport/blenderbim/bim/operator.py

@@ -3363,3 +3363,19 @@ class CalculateEdgeLengths(bpy.types.Operator):
                         obj.data.vertices[edge.vertices[0]].co).length
         bpy.context.scene.BIMProperties.qto_result = str(result)
         return {'FINISHED'}
+
+
+class CalculateFaceAreas(bpy.types.Operator):
+    bl_idname = 'bim.calculate_face_areas'
+    bl_label = 'Calculate Face Areas'
+
+    def execute(self, context):
+        result = 0
+        for obj in bpy.context.selected_objects:
+            if not obj.data or not obj.data.polygons:
+                continue
+            for polygon in obj.data.polygons:
+                if polygon.select:
+                    result += polygon.area
+        bpy.context.scene.BIMProperties.qto_result = str(result)
+        return {'FINISHED'}

src/ifcblenderexport/blenderbim/bim/ui.py

@@ -525,6 +525,8 @@ class BIM_PT_qto(Panel):
 
         row = layout.row(align=True)
         row.operator("bim.calculate_edge_lengths")
+        row = layout.row(align=True)
+        row.operator("bim.calculate_face_areas")
 
 
 class BIM_PT_classifications(Panel):