New feature to calculate side formwork, such as for columns.

src/blenderbim/blenderbim/bim/module/qto/helper.py

@@ -62,7 +62,7 @@ def calculate_formwork_area(objs, context):
     """
     Formwork is defined as the surface area required to cover all exposed
     surfaces of one or more objects, excluding top surfaces (i.e. that have a
-    face normal with a significant Z component).
+    face normal with a significant +Z component).
     """
     copied_objs = []
     result = 0
@@ -105,3 +105,19 @@ def calculate_formwork_area(objs, context):
             continue
         result += polygon.area
     return result
+
+
+def calculate_side_formwork_area(objs, context):
+    """
+    Side formwork is defined as the surface area required to cover all exposed
+    surfaces of one or more objects, excluding top and bottom surfaces (i.e.
+    that have a face normal with a significant Z component).
+    """
+    result = 0
+    for obj in objs:
+        mesh = obj.evaluated_get(context.evaluated_depsgraph_get()).to_mesh()
+        for polygon in mesh.polygons:
+            if abs(polygon.normal.z) > 0.8:
+                continue
+            result += polygon.area
+    return result

src/blenderbim/blenderbim/bim/module/qto/operator.py

@@ -105,6 +105,8 @@ class ExecuteQtoMethod(bpy.types.Operator):
             result = helper.calculate_volumes(selected_mesh_objects, context)
         elif props.qto_methods == "FORMWORK":
             result = helper.calculate_formwork_area(selected_mesh_objects, context)
+        elif props.qto_methods == "SIDE_FORMWORK":
+            result = helper.calculate_side_formwork_area(selected_mesh_objects, context)
         props.qto_result = str(round(result, 3))
         return {"FINISHED"}
 
@@ -134,6 +136,8 @@ class QuantifyObjects(bpy.types.Operator):
                 result = helper.calculate_volumes([obj], context)
             elif props.qto_methods == "FORMWORK":
                 result = helper.calculate_formwork_area([obj], context)
+            elif props.qto_methods == "SIDE_FORMWORK":
+                result = helper.calculate_side_formwork_area([obj], context)
             if not result:
                 continue
             result = round(result, 3)

src/blenderbim/blenderbim/bim/module/qto/prop.py

@@ -37,7 +37,16 @@ class BIMQtoProperties(PropertyGroup):
         items=[
             ("HEIGHT", "Height", "Calculate the Z height of an object"),
             ("VOLUME", "Volume", "Calculate the volume of an object"),
-            ("FORMWORK", "Formwork", "Calculate the exposed formwork for all bottoms and sides of one or more objects"),
+            (
+                "FORMWORK",
+                "Formwork",
+                "Calculate the exposed formwork for all bottoms and sides (e.g. for beams and slabs) of one or more objects",
+            ),
+            (
+                "SIDE_FORMWORK",
+                "Side Formwork",
+                "Calculate the exposed formwork for all sides only (e.g. for columns) of one or more objects",
+            ),
         ],
         name="Qto Methods",
     )

src/blenderbim/test/bim/feature/qto.feature

@@ -29,7 +29,7 @@ Scenario: Calculate object volumes
     When I press "bim.calculate_object_volumes"
     Then "scene.BIMQtoProperties.qto_result" is "8.0"
 
-Scenario: Calculate formwork areas
+Scenario: Execute qto method - formwork areas
     Given an empty Blender session
     And I add a cube
     And I add a cube of size "1" at "1,0,0"
@@ -38,3 +38,11 @@ Scenario: Calculate formwork areas
     When I set "scene.BIMQtoProperties.qto_methods" to "FORMWORK"
     And I press "bim.execute_qto_method"
     Then "scene.BIMQtoProperties.qto_result" is "21.5"
+
+Scenario: Execute qto method - side formwork areas
+    Given an empty Blender session
+    And I add a cube
+    And the object "Cube" is selected
+    When I set "scene.BIMQtoProperties.qto_methods" to "SIDE_FORMWORK"
+    And I press "bim.execute_qto_method"
+    Then "scene.BIMQtoProperties.qto_result" is "16.0"