WIP port unit assignment to partial editing. See #1222.

src/ifcblenderexport/blenderbim/bim/__init__.py

@@ -14,6 +14,7 @@ if bpy is not None:
     import blenderbim.bim.module.geometry as module_geometry
     import blenderbim.bim.module.model as module_model
     import blenderbim.bim.module.spatial as module_spatial
+    import blenderbim.bim.module.unit as module_unit
     from . import ui, prop, operator
 
     classes = [
@@ -320,6 +321,7 @@ if bpy is not None:
     classes.extend(module_geometry.classes)
     classes.extend(module_model.classes)
     classes.extend(module_spatial.classes)
+    classes.extend(module_unit.classes)
 
     def menu_func_export(self, context):
         self.layout.operator(operator.ExportIFC.bl_idname, text="Industry Foundation Classes (.ifc/.ifczip/.ifcjson)")
@@ -360,6 +362,7 @@ if bpy is not None:
         module_geometry.register()
         module_model.register()
         module_spatial.register()
+        module_unit.register()
         bpy.app.handlers.depsgraph_update_pre.append(operator.depsgraph_update_pre_handler)
 
     def unregister():
@@ -380,6 +383,7 @@ if bpy is not None:
         del bpy.types.Camera.BIMCameraProperties
         del bpy.types.TextCurve.BIMTextProperties
         bpy.types.SCENE_PT_unit.remove(ui.ifc_units)
+        module_unit.unregister()
         module_spatial.unregister()
         module_model.unregister()
         module_geometry.unregister()

src/ifcblenderexport/blenderbim/bim/module/context/ui.py

@@ -1,6 +1,7 @@
 from bpy.types import Panel
 from blenderbim.bim.module.context.data import Data
 
+
 class BIM_PT_context(Panel):
     bl_label = "IFC Geometric Representation Contexts"
     bl_idname = "BIM_PT_context"

src/ifcblenderexport/blenderbim/bim/module/unit/__init__.py

@@ -0,0 +1,14 @@
+import bpy
+from . import ui, operator
+
+classes = (
+    operator.AssignUnit,
+)
+
+
+def register():
+    pass
+
+
+def unregister():
+    pass

src/ifcblenderexport/blenderbim/bim/module/unit/assign_unit.py

@@ -0,0 +1,76 @@
+import ifcopenshell.util.unit
+
+
+class Usecase():
+    def __init__(self, file, settings=None):
+        self.file = file
+        self.settings = {
+            "length": {
+                "is_metric": True,
+                "raw": "MILLIMETERS"
+            },
+            "area": {
+                "is_metric": True,
+                "raw": "METERS"
+            },
+            "volume": {
+                "is_metric": True,
+                "raw": "METERS"
+            },
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for unit_type, data in self.settings.items():
+            if data["is_metric"]:
+                data["ifc"] = self.create_metric_unit(unit_type, data)
+            else:
+                data["ifc"] = self.create_imperial_unit(unit_type, data)
+        unit_assignment = self.file.by_type("IfcUnitAssignment")
+        if unit_assignment:
+            unit_assignment = unit_assignment[0]
+            # TODO: handle unit rewriting, which is complicated
+        else:
+            unit_assignment = self.file.createIfcUnitAssignment([u["ifc"] for u in self.settings.values()])
+            self.file.by_type("IfcProject")[0].UnitsInContext = unit_assignment
+        return unit_assignment
+
+    def create_metric_unit(self, unit_type, data):
+        type_prefix = ""
+        if unit_type == "area":
+            type_prefix = "SQUARE_"
+        elif unit_type == "volume":
+            type_prefix = "CUBIC_"
+        return self.file.createIfcSIUnit(
+            None,
+            "{}UNIT".format(unit_type.upper()),
+            ifcopenshell.util.unit.get_prefix(data["raw"]),
+            type_prefix + ifcopenshell.util.unit.get_unit_name(data["raw"]),
+        )
+
+    def create_imperial_unit(self, unit_type, data):
+        if unit_type == "length":
+            dimensional_exponents = self.file.createIfcDimensionalExponents(1, 0, 0, 0, 0, 0, 0)
+            name_prefix = ""
+        elif unit_type == "area":
+            dimensional_exponents = self.file.createIfcDimensionalExponents(2, 0, 0, 0, 0, 0, 0)
+            name_prefix = "square"
+        elif unit_type == "volume":
+            dimensional_exponents = self.file.createIfcDimensionalExponents(3, 0, 0, 0, 0, 0, 0)
+            name_prefix = "cubic"
+        si_unit = self.file.createIfcSIUnit(
+            None,
+            "{}UNIT".format(unit_type.upper()),
+            None,
+            "{}METRE".format(name_prefix.upper() + "_" if name_prefix else ""),
+        )
+        if data["raw"] == "INCHES":
+            name = "{}inch".format(name_prefix + " " if name_prefix else "")
+        elif data["raw"] == "FEET":
+            name = "{}foot".format(name_prefix + " " if name_prefix else "")
+        value_component = self.file.create_entity("IfcReal", **{"wrappedValue": ifcopenshell.util.unit.si_conversions[name]})
+        conversion_factor = self.file.createIfcMeasureWithUnit(value_component, si_unit)
+        return self.file.createIfcConversionBasedUnit(
+            dimensional_exponents, "{}UNIT".format(unit_type.upper()), name, conversion_factor
+        )

src/ifcblenderexport/blenderbim/bim/module/unit/data.py

@@ -0,0 +1,19 @@
+from blenderbim.bim.ifc import IfcStore
+
+
+class Data:
+    is_loaded = False
+    units = {}
+
+    @classmethod
+    def load(cls):
+        file = IfcStore.get_file()
+        if not file:
+            return
+        unit_assignment = file.by_type("IfcUnitAssignment")
+        if not unit_assignment:
+            return
+        for unit in unit_assignment[0].Units:
+            pass
+        # TODO: implement along with UI
+        cls.is_loaded = True

src/ifcblenderexport/blenderbim/bim/module/unit/operator.py

@@ -0,0 +1,40 @@
+import bpy
+import blenderbim.bim.module.unit.assign_unit as assign_unit
+from blenderbim.bim.ifc import IfcStore
+from blenderbim.bim.module.unit.data import Data
+
+
+class AssignUnit(bpy.types.Operator):
+    bl_idname = "bim.assign_unit"
+    bl_label = "Assign Unit"
+
+    def execute(self, context):
+        assign_unit.Usecase(IfcStore.get_file(), self.get_units()).execute()
+        Data.load()
+        return {"FINISHED"}
+
+    def get_units(self):
+        units = {
+            "length": {
+                "ifc": None,
+                "is_metric": bpy.context.scene.unit_settings.system != "IMPERIAL",
+                "raw": bpy.context.scene.unit_settings.length_unit,
+            },
+            "area": {
+                "ifc": None,
+                "is_metric": bpy.context.scene.unit_settings.system != "IMPERIAL",
+                "raw": bpy.context.scene.unit_settings.length_unit,
+            },
+            "volume": {
+                "ifc": None,
+                "is_metric": bpy.context.scene.unit_settings.system != "IMPERIAL",
+                "raw": bpy.context.scene.unit_settings.length_unit,
+            },
+        }
+        for data in units.values():
+            if data["raw"] == "ADAPTIVE":
+                if data["is_metric"]:
+                    data["raw"] = "METERS"
+                else:
+                    data["raw"] = "FEET"
+        return units