Only take used extruders in extruderValues()

cura/BuildVolume.py

@@ -166,6 +166,7 @@ def _onSceneChangeTimerFinished(self):
                 if active_extruder_changed is not None:
                     node.callDecoration("getActiveExtruderChangedSignal").disconnect(self._updateDisallowedAreasAndRebuild)
                 node.decoratorsChanged.disconnect(self._updateNodeListeners)
+            self._updateUsedExtruders()
             self.rebuild()
 
             self._scene_objects = new_scene_objects
@@ -202,7 +203,7 @@ def _updateNodeListeners(self, node: SceneNode):
             per_mesh_stack.propertyChanged.connect(self._onSettingPropertyChanged)
         active_extruder_changed = node.callDecoration("getActiveExtruderChangedSignal")
         if active_extruder_changed is not None:
-            active_extruder_changed.connect(self._updateDisallowedAreasAndRebuild)
+            active_extruder_changed.connect(self._nodeActiveExtruderChanged)
 
     def setWidth(self, width: float) -> None:
         self._width = width
@@ -687,6 +688,7 @@ def _onStackChangeTimerFinished(self) -> None:
             self._depth = self._global_container_stack.getProperty("machine_depth", "value")
             self._shape = self._global_container_stack.getProperty("machine_shape", "value")
 
+            self._updateUsedExtruders()
             self._updateDisallowedAreas()
             self._updateRaftThickness()
             self._extra_z_clearance = self._calculateExtraZClearance(ExtruderManager.getInstance().getUsedExtruderStacks())
@@ -713,6 +715,7 @@ def _onSettingChangeTimerFinished(self) -> None:
         update_disallowed_areas = False
         update_raft_thickness = False
         update_extra_z_clearance = True
+        update_used_extruders = False
 
         for setting_key in self._changed_settings_since_last_rebuild:
             if setting_key in ["print_sequence", "support_mesh", "infill_mesh", "cutting_mesh", "anti_overhang_mesh"]:
@@ -746,12 +749,17 @@ def _onSettingChangeTimerFinished(self) -> None:
 
             if setting_key in self._raft_settings:
                 update_raft_thickness = True
+                update_used_extruders = True
 
             if setting_key in self._extra_z_settings:
                 update_extra_z_clearance = True
 
             if setting_key in self._limit_to_extruder_settings:
                 update_disallowed_areas = True
+                update_used_extruders = True
+
+            if setting_key in self._extruder_settings:
+                update_used_extruders = True
 
             rebuild_me = update_extra_z_clearance or update_disallowed_areas or update_raft_thickness
 
@@ -765,6 +773,9 @@ def _onSettingChangeTimerFinished(self) -> None:
         if update_extra_z_clearance:
             self._extra_z_clearance = self._calculateExtraZClearance(ExtruderManager.getInstance().getUsedExtruderStacks())
 
+        if update_used_extruders:
+            self._updateUsedExtruders()
+
         if rebuild_me:
             self.rebuild()
 
@@ -791,6 +802,22 @@ def _updateMachineSizeProperties(self) -> None:
         self._depth = self._global_container_stack.getProperty("machine_depth", "value")
         self._shape = self._global_container_stack.getProperty("machine_shape", "value")
 
+    def _updateUsedExtruders(self):
+        Logger.info("Updating used extruders")
+        global_container_stack = self._application.getGlobalContainerStack()
+        if not global_container_stack:
+            return
+        used_extruders = ExtruderManager.getInstance().getUsedExtruderStacks()
+        for extruder in global_container_stack.extruderList:
+            used = extruder in used_extruders
+            Logger.info(f"- {extruder.getId()}: {used}")
+            changed = (used == extruder.getProperty("extruder_used", "value"))
+            extruder.setProperty("extruder_used", "value", used)
+
+    def _nodeActiveExtruderChanged(self):
+        self._updateDisallowedAreasAndRebuild()
+        self._updateUsedExtruders()
+
     def _updateDisallowedAreasAndRebuild(self):
         """Calls :py:meth:`cura.BuildVolume._updateDisallowedAreas` and makes sure the changes appear in the scene.
 

cura/Settings/CuraFormulaFunctions.py

@@ -67,16 +67,19 @@ def _getActiveExtruders(self, context: Optional["PropertyEvaluationContext"] = N
 
         global_stack = machine_manager.activeMachine
 
-        result = []
+        enabled_extruders = []
+        used_extruders = []
         for extruder in extruder_manager.getActiveExtruderStacks():
             if not extruder.isEnabled:
                 continue
             # only include values from extruders that are "active" for the current machine instance
             if int(extruder.getMetaDataEntry("position")) >= global_stack.getProperty("machine_extruder_count", "value", context = context):
                 continue
-            result.append(extruder)
+            enabled_extruders.append(extruder)
+            if extruder.getProperty("extruder_used", "value"):
+                used_extruders.append(extruder)
 
-        return result
+        return used_extruders if used_extruders else enabled_extruders
 
     # Gets all extruder values as a list for the given property.
     def getValuesInAllExtruders(self, property_key: str,

resources/definitions/fdmprinter.def.json

@@ -289,6 +289,17 @@
                     "settable_per_extruder": false,
                     "settable_per_meshgroup": false
                 },
+                "extruder_used":
+                {
+                    "default_value": true,
+                    "description": "Is this extruder used for printing. This setting is controlled by Cura automatically.",
+                    "label": "Extruder Used",
+                    "settable_globally": false,
+                    "settable_per_extruder": true,
+                    "settable_per_mesh": false,
+                    "settable_per_meshgroup": false,
+                    "type": "bool"
+                },
                 "machine_nozzle_tip_outer_diameter":
                 {
                     "label": "Outer Nozzle Diameter",
@@ -2482,7 +2493,8 @@
                     "maximum_value_warning": "285",
                     "enabled": "machine_heated_build_volume",
                     "settable_per_mesh": false,
-                    "settable_per_extruder": false
+                    "settable_per_extruder": false,
+                    "depends_on_settings": ["extruder_used"]
                 },
                 "material_print_temperature":
                 {
@@ -2595,7 +2607,8 @@
                     "enabled": "machine_heated_bed and machine_gcode_flavor != \"UltiGCode\"",
                     "settable_per_mesh": false,
                     "settable_per_extruder": false,
-                    "settable_per_meshgroup": false
+                    "settable_per_meshgroup": false,
+                    "depends_on_settings": ["extruder_used"]
                 },
                 "material_bed_temperature_layer_0":
                 {