Fix ability to create grids which was totally broken

src/ifcblenderexport/blenderbim/bim/ifc.py

@@ -33,12 +33,14 @@ class IfcStore:
     @staticmethod
     def link_element(element, obj):
         IfcStore.id_map[element.id()] = obj
-        IfcStore.guid_map[element.GlobalId] = obj
+        if hasattr(element, "GlobalId"):
+            IfcStore.guid_map[element.GlobalId] = obj
         obj.BIMObjectProperties.ifc_definition_id = element.id()
 
     @staticmethod
     def unlink_element(element, obj=None):
         del IfcStore.id_map[element.id()]
-        del IfcStore.guid_map[element.GlobalId]
+        if hasattr(element, "GlobalId"):
+            del IfcStore.guid_map[element.GlobalId]
         if obj:
             obj.BIMObjectProperties.ifc_definition_id = 0

src/ifcblenderexport/blenderbim/bim/module/grid/create_grid_axis.py

@@ -0,0 +1,53 @@
+import ifcopenshell
+import ifcopenshell.util.unit
+import ifcopenshell.util.placement
+from mathutils import Matrix  # For now, we depend on Blender
+from blenderbim.bim.module.owner.api import create_owner_history
+
+
+class Usecase:
+    def __init__(self, file, settings=None):
+        self.file = file
+        self.settings = {
+            "AxisTag": "A",
+            "AxisCurve": None,  # A Blender object
+            "SameSense": True,
+            "UVWAxes": "UAxes",  # Choose which axes
+            "Grid": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        self.settings["unit_scale"] = ifcopenshell.util.unit.calculate_unit_scale(self.file)
+        points = [
+            Matrix(ifcopenshell.util.placement.get_local_placement(self.settings["Grid"].ObjectPlacement)).inverted()
+            @ (self.settings["AxisCurve"].matrix_world @ v.co)
+            for v in self.settings["AxisCurve"].data.vertices[0:2]
+        ]
+        self.settings["AxisCurve"] = self.file.createIfcPolyline(
+            [
+                self.create_cartesian_point(points[0][0], points[0][1], points[0][2]),
+                self.create_cartesian_point(points[1][0], points[1][1], points[1][2]),
+            ]
+        )
+        element = self.file.create_entity("IfcGridAxis", **{
+            "AxisTag": self.settings["AxisTag"],
+            "AxisCurve": self.settings["AxisCurve"],
+            "SameSense": self.settings["SameSense"]
+        })
+        axes = list(getattr(self.settings["Grid"], self.settings["UVWAxes"]) or [])
+        axes.append(element)
+        setattr(self.settings["Grid"], self.settings["UVWAxes"], axes)
+        return element
+
+    def create_cartesian_point(self, x, y, z=None):
+        x = self.convert_si_to_unit(x)
+        y = self.convert_si_to_unit(y)
+        if z is None:
+            return self.file.createIfcCartesianPoint((x, y))
+        z = self.convert_si_to_unit(z)
+        return self.file.createIfcCartesianPoint((x, y, z))
+
+    def convert_si_to_unit(self, co):
+        return co / self.settings["unit_scale"]

src/ifcblenderexport/blenderbim/bim/module/model/grid.py

@@ -1,19 +1,16 @@
 import bpy
+import blenderbim.bim.module.grid.create_grid_axis as create_grid_axis
 from bpy.types import Operator
 from bpy.props import FloatProperty, IntProperty
-from bpy_extras.object_utils import AddObjectHelper, object_data_add
 from mathutils import Vector
+from blenderbim.bim.ifc import IfcStore
 
 
 def add_object(self, context):
-    obj = object_data_add(context, None, operator=self)
-    obj.name = "IfcGrid/Grid"
-    name = obj.name.split("/")[1]
+    obj = bpy.data.objects.new("Grid", None)
+    obj.name = "Grid"
 
-    default_collection = obj.users_collection[0]
-    default_collection.objects.unlink(obj)
-
-    collection = bpy.data.collections.new("IfcGrid/" + name)
+    collection = bpy.data.collections.new(obj.name)
     has_site_collection = False
     for child in bpy.context.view_layer.layer_collection.children:
         if "IfcProject/" not in child.name:
@@ -28,6 +25,13 @@ def add_object(self, context):
         bpy.context.view_layer.active_layer_collection.collection.children.link(collection)
     collection.objects.link(obj)
 
+    self.file = IfcStore.get_file()
+    if self.file:
+        bpy.ops.bim.assign_class(obj=obj.name, ifc_class="IfcGrid")
+        grid = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
+        if has_site_collection:
+            bpy.ops.bim.assign_container(relating_structure=grandchild.name, related_element=obj.name)
+
     axes_collection = bpy.data.collections.new("UAxes")
     collection.children.link(axes_collection)
     for i in range(0, self.total_u):
@@ -39,14 +43,16 @@ def add_object(self, context):
         faces = []
         mesh = bpy.data.meshes.new(name="Grid Axis")
         mesh.from_pydata(verts, edges, faces)
-        obj = object_data_add(context, mesh, operator=self)
         tag = chr(ord("A") + i)
-        obj.name = "IfcGridAxis/" + tag
-        default_collection.objects.unlink(obj)
+        obj = bpy.data.objects.new(f"IfcGridAxis/{tag}", mesh)
+
         axes_collection.objects.link(obj)
-        attribute = obj.BIMObjectProperties.attributes.add()
-        attribute.name = "AxisTag"
-        attribute.string_value = tag
+
+        if self.file:
+            result = create_grid_axis.Usecase(
+                self.file, {"AxisTag": tag, "AxisCurve": obj, "UVWAxes": "UAxes", "Grid": grid}
+            ).execute()
+            obj.BIMObjectProperties.ifc_definition_id = result.id()
 
     axes_collection = bpy.data.collections.new("VAxes")
     collection.children.link(axes_collection)
@@ -59,17 +65,19 @@ def add_object(self, context):
         faces = []
         mesh = bpy.data.meshes.new(name="Grid Axis")
         mesh.from_pydata(verts, edges, faces)
-        obj = object_data_add(context, mesh, operator=self)
         tag = str(i + 1).zfill(2)
-        obj.name = "IfcGridAxis/" + tag
-        default_collection.objects.unlink(obj)
+        obj = bpy.data.objects.new(f"IfcGridAxis/{tag}", mesh)
+
         axes_collection.objects.link(obj)
-        attribute = obj.BIMObjectProperties.attributes.add()
-        attribute.name = "AxisTag"
-        attribute.string_value = tag
+
+        if IfcStore.get_file():
+            result = create_grid_axis.Usecase(
+                self.file, {"AxisTag": tag, "AxisCurve": obj, "UVWAxes": "VAxes", "Grid": grid}
+            ).execute()
+            obj.BIMObjectProperties.ifc_definition_id = result.id()
 
 
-class BIM_OT_add_object(Operator, AddObjectHelper):
+class BIM_OT_add_object(Operator):
     bl_idname = "mesh.add_grid"
     bl_label = "Grid"
     bl_options = {"REGISTER", "UNDO"}