You can now change the radius of existing circles. Radius settings are remembered.

src/blenderbim/blenderbim/bim/module/cad/__init__.py

@@ -17,7 +17,7 @@
 # along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
 
 import bpy
-from . import operator, workspace
+from . import operator, prop, workspace
 
 classes = (
     operator.AddIfcArcIndexFillet,
@@ -28,6 +28,7 @@ classes = (
     operator.CadMitre,
     operator.CadOffset,
     operator.CadTrimExtend,
+    prop.BIMCadProperties,
     workspace.CadHotkey,
 )
 
@@ -35,8 +36,10 @@ classes = (
 def register():
     if not bpy.app.background:
         bpy.utils.register_tool(workspace.CadTool, after={"builtin.transform"}, separator=True, group=True)
+    bpy.types.Scene.BIMCadProperties = bpy.props.PointerProperty(type=prop.BIMCadProperties)
 
 
 def unregister():
     if not bpy.app.background:
         bpy.utils.unregister_tool(workspace.CadTool)
+    del bpy.types.Scene.BIMCadProperties

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

@@ -539,8 +539,41 @@ class AddIfcCircle(bpy.types.Operator):
         return bool(obj) and obj.type == "MESH"
 
     def execute(self, context):
-        obj = context.active_object
+        if self.has_selected_existing_circle(context):
+            self.change_radius(context)
+        else:
+            self.create_circle(context)
+        return {"FINISHED"}
 
+    def has_selected_existing_circle(self, context):
+        obj = context.active_object
+        bm = bmesh.from_edit_mesh(obj.data)
+        verts = [v for v in bm.verts if v.select and not v.hide]
+        if len(verts) != 2:
+            return False
+        groups = []
+        for i, group in enumerate(obj.vertex_groups):
+            if "IFCCIRCLE" in group.name:
+                groups.append(i)
+        bm.verts.layers.deform.verify()
+        deform_layer = bm.verts.layers.deform.active
+        for group in groups:
+            if group in verts[0][deform_layer] and group in verts[1][deform_layer]:
+                return True
+
+    def change_radius(self, context):
+        obj = context.active_object
+        bm = bmesh.from_edit_mesh(obj.data)
+        verts = [v for v in bm.verts if v.select and not v.hide]
+        center = verts[0].co.lerp(verts[1].co, 0.5)
+        verts[0].co = center + ((verts[0].co - center).normalized() * self.radius)
+        verts[1].co = center + ((verts[1].co - center).normalized() * self.radius)
+        bm.verts.index_update()
+        bm.edges.index_update()
+        bmesh.update_edit_mesh(obj.data)
+
+    def create_circle(self, context):
+        obj = context.active_object
         bpy.ops.object.mode_set(mode="OBJECT")
         # The last group may be the result of a prior run of this operator.
         # I tried looping through all groups but Blender group indices seem to behave unpredictably.
@@ -570,7 +603,6 @@ class AddIfcCircle(bpy.types.Operator):
         bm.verts.index_update()
         bm.edges.index_update()
         bmesh.update_edit_mesh(obj.data)
-        return {"FINISHED"}
 
 
 class AddIfcArcIndexFillet(bpy.types.Operator):

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

@@ -0,0 +1,28 @@
+# BlenderBIM Add-on - OpenBIM Blender Add-on
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of BlenderBIM Add-on.
+#
+# BlenderBIM Add-on is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# BlenderBIM Add-on is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with BlenderBIM Add-on.  If not, see <http://www.gnu.org/licenses/>.
+
+import bpy
+from blenderbim.bim.module.model.data import AuthoringData
+from blenderbim.bim.module.model.root import ConstrTypeEntityNotFound
+from bpy.types import PropertyGroup
+
+
+class BIMCadProperties(PropertyGroup):
+    resolution: bpy.props.IntProperty(name="Arc Resolution", min=1, default=1)
+    radius: bpy.props.FloatProperty(name="Radius", default=0.1)
+    distance: bpy.props.FloatProperty(name="Distance", default=0.1)

src/blenderbim/blenderbim/bim/module/cad/workspace.py

@@ -123,36 +123,35 @@ class CadHotkey(bpy.types.Operator):
     bl_label = "CAD Hotkey"
     bl_options = {"REGISTER", "UNDO"}
     hotkey: bpy.props.StringProperty()
-    resolution: bpy.props.IntProperty(name="Arc Resolution", min=1, default=1)
-    radius: bpy.props.FloatProperty(name="Radius", default=0.1)
-    distance: bpy.props.FloatProperty(name="Distance", default=0.1)
 
     def execute(self, context):
+        self.props = context.scene.BIMCadProperties
         getattr(self, f"hotkey_{self.hotkey}")()
         return {"FINISHED"}
 
     def draw(self, context):
+        props = context.scene.BIMCadProperties
         if self.hotkey == "S_C":
             if self.is_profile():
                 row = self.layout.row()
-                row.prop(self, "radius")
+                row.prop(props, "radius")
         elif self.hotkey == "S_F":
             if not self.is_profile():
                 row = self.layout.row()
-                row.prop(self, "resolution")
+                row.prop(props, "resolution")
             row = self.layout.row()
-            row.prop(self, "radius")
+            row.prop(props, "radius")
         elif self.hotkey == "S_O":
             row = self.layout.row()
-            row.prop(self, "distance")
+            row.prop(props, "distance")
         elif self.hotkey == "S_V":
             if not self.is_profile():
                 row = self.layout.row()
-                row.prop(self, "resolution")
+                row.prop(props, "resolution")
 
     def hotkey_S_C(self):
         if self.is_profile():
-            bpy.ops.bim.add_ifccircle(radius=self.radius)
+            bpy.ops.bim.add_ifccircle(radius=self.props.radius)
         else:
             bpy.ops.bim.cad_arc_from_2_points()
 
@@ -161,12 +160,12 @@ class CadHotkey(bpy.types.Operator):
 
     def hotkey_S_F(self):
         if self.is_profile():
-            bpy.ops.bim.add_ifcarcindex_fillet(radius=self.radius)
+            bpy.ops.bim.add_ifcarcindex_fillet(radius=self.props.radius)
         else:
-            bpy.ops.bim.cad_fillet(resolution=self.resolution, radius=self.radius)
+            bpy.ops.bim.cad_fillet(resolution=self.props.resolution, radius=self.props.radius)
 
     def hotkey_S_O(self):
-        bpy.ops.bim.cad_offset(distance=self.distance)
+        bpy.ops.bim.cad_offset(distance=self.props.distance)
 
     def hotkey_S_Q(self):
         bpy.ops.bim.edit_extrusion_profile()