settings flow direction without jumping to ports

https://imgur.com/a/F00tG7g

src/blenderbim/blenderbim/bim/module/system/data.py

@@ -102,12 +102,13 @@ class PortData:
             "port_connected_object": cls.port_connected_object() if is_port else None,
             "port_relating_object": cls.port_relating_object() if is_port else None,
         }
+        # AFTER located_ports_data
+        cls.data["selected_objects_flow_direction"] = cls.selected_objects_flow_direction() if not is_port else None
         cls.is_loaded = True
 
     @classmethod
     def total_ports(cls):
-        element = tool.Ifc.get_entity(bpy.context.active_object)
-        return len(ifcopenshell.util.system.get_ports(element))
+        return len(ifcopenshell.util.system.get_ports(cls.element))
 
     @classmethod
     def is_port(cls):
@@ -127,21 +128,26 @@ class PortData:
 
     @classmethod
     def located_ports_data(cls):
-        element = tool.Ifc.get_entity(bpy.context.active_object)
-        ports = ifcopenshell.util.system.get_ports(element)
+        ports = ifcopenshell.util.system.get_ports(cls.element)
 
         data = []
         for port in ports:
             port_obj = tool.Ifc.get_object(port)
             connected_port = tool.System.get_connected_port(port)
             if connected_port:
-                connected_element = tool.Ifc.get_object(tool.System.get_port_relating_element(connected_port))
+                connected_obj = tool.Ifc.get_object(tool.System.get_port_relating_element(connected_port))
             else:
-                connected_element = None
+                connected_obj = None
 
-            data.append((port, port_obj, connected_element))
+            data.append((port, port_obj, connected_obj))
         return data
 
+    @classmethod
+    def selected_objects_flow_direction(cls):
+        for port, port_obj, connected_obj in cls.data["located_ports_data"]:
+            if connected_obj in bpy.context.selected_objects:
+                return port.FlowDirection
+
 
 class SystemDecorationData:
     data = {}

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

@@ -270,12 +270,59 @@ class SetFlowDirection(bpy.types.Operator, Operator):
     bl_options = {"REGISTER", "UNDO"}
     direction: bpy.props.StringProperty()
 
+    @classmethod
+    def description(cls, context, operator):
+        if not PortData.is_loaded:
+            PortData.load()
+
+        port = PortData.data["is_port"]
+        if port:
+            return f"Set port flow direction to {operator.direction}"
+        else:
+            return f"Set flow direction to {operator.direction} for active element relatively to the selected"
+
+    @classmethod
+    def poll(cls, context):
+        if not PortData.is_loaded:
+            PortData.load()
+
+        port = PortData.data["is_port"]
+        if not port and not len(context.selected_objects) == 2:
+            cls.poll_message_set("Need to select port or 2 connected objects.")
+            return False
+        return True
+
     def _execute(self, context):
-        port = tool.Ifc.get_entity(context.active_object)
-        second_port = tool.System.get_connected_port(port)
-        if not second_port:
-            self.report({"ERROR"}, "To set flow direction port has to be connected to another one.")
-            return
-        core.set_flow_direction(
-            tool.Ifc, tool.System, port=tool.Ifc.get_entity(context.active_object), direction=self.direction
-        )
+        element = tool.Ifc.get_entity(context.active_object)
+
+        if element.is_a("IfcDistributionPort"):
+            second_port = tool.System.get_connected_port(element)
+            if not second_port:
+                self.report({"ERROR"}, "To set flow direction port has to be connected to another one.")
+                return
+            core.set_flow_direction(tool.Ifc, tool.System, port=element, direction=self.direction)
+            return {"FINISHED"}
+
+        selected_elements = [
+            entity
+            for entity in (tool.Ifc.get_entity(o) for o in context.selected_objects)
+            if entity and tool.System.is_mep_element(element)
+        ]
+
+        if len(selected_elements) != 2:
+            self.report({"ERROR"}, "To set flow direction selected two connected MEP elements or just 1 port.")
+            return {"CANCELLED"}
+
+        other_element = selected_elements[selected_elements[0] == element]
+        active_element_ports = tool.System.get_ports(element)
+        other_element_ports = tool.System.get_ports(other_element)
+
+        for port in active_element_ports:
+            connected_port = tool.System.get_connected_port(port)
+            if connected_port in other_element_ports:
+                core.set_flow_direction(tool.Ifc, tool.System, port=port, direction=self.direction)
+                tool.Blender.update_viewport()
+                return {"FINISHED"}
+
+        self.report({"ERROR"}, "Selected elements are not connected to set the flow direction")
+        return {"CANCELLED"}

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

@@ -24,10 +24,10 @@ from blenderbim.bim.module.system.data import SystemData, ObjectSystemData, Port
 
 
 FLOW_DIRECTION_TO_ICON = {
-    "SOURCE": "FORWARD",
-    "SINK": "BACK",
+    "SOURCE": "REMOVE",
+    "SINK": "ADD",
     "SOURCEANDSINK": "ARROW_LEFTRIGHT",
-    "NOTDEFINED": "RESTRICT_INSTANCED_ON",
+    "NOTDEFINED": "CHECKBOX_DEHLT",
 }
 
 
@@ -179,6 +179,19 @@ class BIM_PT_ports(Panel):
         if total_ports == 0:
             return
 
+        row = self.layout.row(align=True)
+        row.label(text="Change Flow Direction:")
+
+        current_flow_direction = PortData.data["selected_objects_flow_direction"]
+        for flow_direction in FLOW_DIRECTION_TO_ICON.keys():
+            row.operator(
+                "bim.set_flow_direction",
+                icon=FLOW_DIRECTION_TO_ICON[flow_direction],
+                depress=flow_direction == current_flow_direction,
+                text="",
+            ).direction = flow_direction
+        row.enabled = len(context.selected_objects) == 2
+
         row = self.layout.row(align=True)
         row.label(text="Ports located on object and connected objects:")
         row = self.layout.row(align=True)
@@ -270,16 +283,15 @@ class BIM_PT_port(Panel):
         else:
             row.label(text="Port is not connected to any element")
 
-        # TODO: replace with enum property?
         row = layout.row(align=True)
         row.label(text="Change Flow Direction:")
         for flow_direction in FLOW_DIRECTION_TO_ICON.keys():
-            row = layout.row()
             row.operator(
-                "bim.set_flow_direction", icon=FLOW_DIRECTION_TO_ICON[flow_direction], text=flow_direction
+                "bim.set_flow_direction",
+                icon=FLOW_DIRECTION_TO_ICON[flow_direction],
+                depress=flow_direction == current_flow_direction,
+                text="",
             ).direction = flow_direction
-            if flow_direction == current_flow_direction:
-                row.enabled = False
 
 
 class BIM_UL_systems(UIList):