ifc array modifier: adds the option to choose between "total" and "increment" as dimension input

src/blenderbim/blenderbim/bim/module/model/array.py

@@ -34,7 +34,7 @@ class AddArray(bpy.types.Operator, tool.Ifc.Operator):
         obj = context.active_object
         element = tool.Ifc.get_entity(obj)
 
-        array = {"children": [], "count": 1, "x": 0.0, "y": 0.0, "z": 0.0, "use_local_space": True}
+        array = {"children": [], "count": 1, "x": 0.0, "y": 0.0, "z": 0.0, "use_local_space": True, "dimension_input_type": "Increment"}
 
         pset = ifcopenshell.util.element.get_pset(element, "BBIM_Array")
 
@@ -81,6 +81,7 @@ class EnableEditingArray(bpy.types.Operator, tool.Ifc.Operator):
         props.y = data["y"]
         props.z = data["z"]
         props.use_local_space = data.get("use_local_space", False)
+        props.dimension_input_type = data.get("dimension_input_type", "Increment")
         props.is_editing = self.item
         return {"FINISHED"}
 
@@ -105,6 +106,7 @@ class EditArray(bpy.types.Operator, tool.Ifc.Operator):
             "y": props.y,
             "z": props.z,
             "use_local_space": props.use_local_space,
+            "dimension_input_type": props.dimension_input_type,
         }
 
         props.is_editing = -1

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

@@ -261,6 +261,14 @@ class BIMArrayProperties(PropertyGroup):
         description="Use local space for array items offset instead of world space",
         default=True,
     )
+    dimension_input_type: bpy.props.EnumProperty(
+        items=(
+            ("Increment", "Increment", ""),
+            ("Total", "Total", ""),
+        ),
+        name="Type of input dimension",
+        default="Increment",
+    )
 
 
 class BIMStairProperties(PropertyGroup):

src/blenderbim/blenderbim/bim/module/model/ui.py

@@ -224,6 +224,8 @@ class BIM_PT_array(bpy.types.Panel):
                     row.operator("bim.edit_array", icon="CHECKMARK", text="").item = i
                     row.operator("bim.disable_editing_array", icon="CANCEL", text="")
                     row = box.row(align=True)
+                    row.prop(props, "dimension_input_type")
+                    row = box.row(align=True)
                     row.prop(props, "use_local_space")
                     row = box.row(align=True)
                     row.prop(props, "x")
@@ -236,6 +238,8 @@ class BIM_PT_array(bpy.types.Panel):
                     row.operator("bim.enable_editing_array", icon="GREASEPENCIL", text="").item = i
                     row.operator("bim.remove_array", icon="X", text="").item = i
                     row = box.row(align=True)
+                    row.label(text=f"Dimension input type: {array.get('dimension_input_type', 'Increment')}")
+                    row = box.row(align=True)
                     row.label(text=f"Use Local Space: {array.get('use_local_space', False)}")
                     row = box.row(align=True)
                     row.label(text=f"X: {array['x']}")

src/blenderbim/blenderbim/tool/model.py

@@ -419,7 +419,11 @@ class Model(blenderbim.core.tool.Model):
             total_existing_children = len(array["children"])
             children_elements = []
             children_objs = []
-            base_offset = Vector([array["x"], array["y"], array["z"]]) * unit_scale
+            if array['dimension_input_type'] == "Total":
+                divider = array["count"] -1
+                base_offset = Vector([array["x"] / divider, array["y"] / divider, array["z"] / divider]) * unit_scale
+            else:
+                base_offset = Vector([array["x"], array["y"], array["z"]]) * unit_scale
             for i in range(array["count"]):
                 if i == 0:
                     continue