CURA-4400 introduced value -1 for extruder number setting (not optional_extruder); this one takes the defaultExtruderPosition in MachineManager

cura/Settings/ExtruderManager.py

@@ -241,6 +241,13 @@ class ExtruderManager(QObject):
             result.append(extruder_stack.getProperty(setting_key, prop))
         return result
 
+    def extruderValueWithDefault(self, value):
+        machine_manager = self._application.getMachineManager()
+        if value == "-1":
+            return machine_manager.defaultExtruderPosition
+        else:
+            return value
+
     ##  Gets the extruder stacks that are actually being used at the moment.
     #
     #   An extruder stack is being used if it is the extruder to print any mesh
@@ -252,7 +259,7 @@ class ExtruderManager(QObject):
     #
     #   \return A list of extruder stacks.
     def getUsedExtruderStacks(self) -> List["ContainerStack"]:
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        global_stack = self._application.getGlobalContainerStack()
         container_registry = ContainerRegistry.getInstance()
 
         used_extruder_stack_ids = set()
@@ -302,16 +309,19 @@ class ExtruderManager(QObject):
 
         # Check support extruders
         if support_enabled:
-            used_extruder_stack_ids.add(self.extruderIds[str(global_stack.getProperty("support_infill_extruder_nr", "value"))])
+            used_extruder_stack_ids.add(self.extruderIds[self.extruderValueWithDefault(str(global_stack.getProperty("support_infill_extruder_nr", "value")))])
-            used_extruder_stack_ids.add(self.extruderIds[str(global_stack.getProperty("support_extruder_nr_layer_0", "value"))])
+            used_extruder_stack_ids.add(self.extruderIds[self.extruderValueWithDefault(str(global_stack.getProperty("support_extruder_nr_layer_0", "value")))])
             if support_bottom_enabled:
-                used_extruder_stack_ids.add(self.extruderIds[str(global_stack.getProperty("support_bottom_extruder_nr", "value"))])
+                used_extruder_stack_ids.add(self.extruderIds[self.extruderValueWithDefault(str(global_stack.getProperty("support_bottom_extruder_nr", "value")))])
             if support_roof_enabled:
-                used_extruder_stack_ids.add(self.extruderIds[str(global_stack.getProperty("support_roof_extruder_nr", "value"))])
+                used_extruder_stack_ids.add(self.extruderIds[self.extruderValueWithDefault(str(global_stack.getProperty("support_roof_extruder_nr", "value")))])
 
         # The platform adhesion extruder. Not used if using none.
         if global_stack.getProperty("adhesion_type", "value") != "none":
-            used_extruder_stack_ids.add(self.extruderIds[str(global_stack.getProperty("adhesion_extruder_nr", "value"))])
+            extruder_nr = str(global_stack.getProperty("adhesion_extruder_nr", "value"))
+            if extruder_nr == "-1":
+                extruder_nr = Application.getInstance().getMachineManager().defaultExtruderPosition
+            used_extruder_stack_ids.add(self.extruderIds[extruder_nr])
 
         try:
             return [container_registry.findContainerStacks(id = stack_id)[0] for stack_id in used_extruder_stack_ids]

cura/Settings/MachineManager.py

@@ -699,7 +699,6 @@ class MachineManager(QObject):
             return containers[0].definition.getId()
 
     ##  Update extruder number to a valid value when the number of extruders are changed, or when an extruder is changed
-    #   \return if any properties has been added
     def correctExtruderSettings(self):
         extruder_count = self._global_container_stack.getProperty("machine_extruder_count", "value")
 
@@ -717,22 +716,6 @@ class MachineManager(QObject):
                 self._global_container_stack.userChanges.removeInstance(setting_key)
                 Logger.log("d", "Reset [%s] because its old value [%s] is no longer valid (2)", setting_key, old_value)
 
-        added_properties = False
-        for setting_key in self._global_container_stack.definition.getAllKeys():
-            if not self._global_container_stack.getProperty(setting_key, "type") in ("extruder", "optional_extruder"):
-                continue
-            current_value = self._global_container_stack.getProperty(setting_key, "value")
-            if current_value is None:
-                continue
-            if current_value == "-1":
-                continue
-            if not self._global_container_stack.extruders[str(current_value)].isEnabled:
-                self._global_container_stack.userChanges.setProperty(setting_key, "value", str(self._default_extruder_position))
-                added_properties = True
-                Logger.log("d", "Change [%s] to [%s] because its value [%s] is not valid", setting_key, self._default_extruder_position, current_value)
-
-        return added_properties
-
     ##  Set the amount of extruders on the active machine (global stack)
     #   \param extruder_count int the number of extruders to set
     def setActiveMachineExtruderCount(self, extruder_count):

plugins/CuraEngineBackend/CuraEngineBackend.py

@@ -91,6 +91,8 @@ class CuraEngineBackend(QObject, Backend):
         self._onGlobalStackChanged()
 
         Application.getInstance().stacksValidationFinished.connect(self._onStackErrorCheckFinished)
+        # extruder enable / disable. Actually wanted to use machine manager here, but the initialization order causes it to crash
+        ExtruderManager.getInstance().extrudersChanged.connect(self._extruderChanged)
 
         # A flag indicating if an error check was scheduled
         # If so, we will stop the auto-slice timer and start upon the error check
@@ -773,3 +775,9 @@ class CuraEngineBackend(QObject, Backend):
     def tickle(self):
         if self._use_timer:
             self._change_timer.start()
+
+    def _extruderChanged(self):
+        for build_plate_number in range(Application.getInstance().getMultiBuildPlateModel().maxBuildPlate + 1):
+            if build_plate_number not in self._build_plates_to_be_sliced:
+                self._build_plates_to_be_sliced.append(build_plate_number)
+        self._invokeSlice()

plugins/CuraEngineBackend/StartSliceJob.py

@@ -280,9 +280,15 @@ class StartSliceJob(Job):
     #   \return A dictionary of replacement tokens to the values they should be
     #   replaced with.
     def _buildReplacementTokens(self, stack) -> dict:
+        default_extruder_position = Application.getInstance().getMachineManager().defaultExtruderPosition
         result = {}
         for key in stack.getAllKeys():
-            result[key] = stack.getProperty(key, "value")
+            setting_type = stack.getProperty(key, "type")
+            value = stack.getProperty(key, "value")
+            if setting_type == "extruder" and value == "-1":
+                # replace with the default value
+                value = default_extruder_position
+            result[key] = value
             Job.yieldThread()
 
         result["print_bed_temperature"] = result["material_bed_temperature"] # Renamed settings.

resources/definitions/fdmprinter.def.json

@@ -3458,7 +3458,7 @@
                     "label": "Support Extruder",
                     "description": "The extruder train to use for printing the support. This is used in multi-extrusion.",
                     "type": "extruder",
-                    "default_value": "0",
+                    "default_value": "-1",
                     "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                     "settable_per_mesh": false,
                     "settable_per_extruder": false,
@@ -3468,7 +3468,7 @@
                             "label": "Support Infill Extruder",
                             "description": "The extruder train to use for printing the infill of the support. This is used in multi-extrusion.",
                             "type": "extruder",
-                            "default_value": "0",
+                            "default_value": "-1",
                             "value": "support_extruder_nr",
                             "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                             "settable_per_mesh": false,
@@ -3479,7 +3479,7 @@
                             "label": "First Layer Support Extruder",
                             "description": "The extruder train to use for printing the first layer of support infill. This is used in multi-extrusion.",
                             "type": "extruder",
-                            "default_value": "0",
+                            "default_value": "-1",
                             "value": "support_extruder_nr",
                             "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                             "settable_per_mesh": false,
@@ -3490,7 +3490,7 @@
                             "label": "Support Interface Extruder",
                             "description": "The extruder train to use for printing the roofs and floors of the support. This is used in multi-extrusion.",
                             "type": "extruder",
-                            "default_value": "0",
+                            "default_value": "-1",
                             "value": "support_extruder_nr",
                             "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                             "settable_per_mesh": false,
@@ -3502,7 +3502,7 @@
                                     "label": "Support Roof Extruder",
                                     "description": "The extruder train to use for printing the roofs of the support. This is used in multi-extrusion.",
                                     "type": "extruder",
-                                    "default_value": "0",
+                                    "default_value": "-1",
                                     "value": "support_interface_extruder_nr",
                                     "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                                     "settable_per_mesh": false,
@@ -3513,7 +3513,7 @@
                                     "label": "Support Floor Extruder",
                                     "description": "The extruder train to use for printing the floors of the support. This is used in multi-extrusion.",
                                     "type": "extruder",
-                                    "default_value": "0",
+                                    "default_value": "-1",
                                     "value": "support_interface_extruder_nr",
                                     "enabled": "(support_enable or support_tree_enable) and machine_extruder_count > 1",
                                     "settable_per_mesh": false,
@@ -4184,7 +4184,7 @@
                     "label": "Build Plate Adhesion Extruder",
                     "description": "The extruder train to use for printing the skirt/brim/raft. This is used in multi-extrusion.",
                     "type": "extruder",
-                    "default_value": "0",
+                    "default_value": "-1",
                     "enabled": "machine_extruder_count > 1 and resolveOrValue('adhesion_type') != 'none'",
                     "settable_per_mesh": false,
                     "settable_per_extruder": false

resources/qml/Settings/SettingExtruder.qml

@@ -72,6 +72,24 @@ SettingItem
             value: control.currentText != "" ? control.model.getItem(control.currentIndex).color : ""
         }
 
+        Binding
+        {
+            target: control
+            property: "currentIndex"
+            value:
+            {
+                if(propertyProvider.properties.value == -1)
+                {
+                    // TODO: accidently the extruder position is also the index. fix it
+                    return Cura.MachineManager.defaultExtruderPosition;
+                }
+                return propertyProvider.properties.value
+            }
+            // Sometimes when the value is already changed, the model is still being built.
+            // The when clause ensures that the current index is not updated when this happens.
+            when: control.model.items.length > 0
+        }
+
         indicator: UM.RecolorImage
         {
             id: downArrow