add: Dynamic changes to Behaviour Patterns at runtime

addons/behaviour_toolkit/behaviour_toolkit.gd

@@ -1,3 +1,5 @@
 @icon("res://addons/behaviour_toolkit/icons/Gear.svg")
 class_name BehaviourToolkit extends Node
-## The main node of the BehaviourToolkit plugin.
+## The main node of the Behaviour Toolkit plugin.
+##
+## All nodes of Behaviour Toolkit pluign extend it.

addons/behaviour_toolkit/behaviour_tree/bt_behaviour.gd

@@ -1,7 +1,11 @@
 @icon("res://addons/behaviour_toolkit/icons/BTBehaviour.svg")
 class_name BTBehaviour extends BehaviourToolkit
+## Base class for Behaviours used in the behaviour tree.
+##
+## TODO
 
 
+## Status enum returned by nodes executing behaviours.
 enum BTStatus {
 	SUCCESS,
 	FAILURE,

addons/behaviour_toolkit/behaviour_tree/bt_composite.gd

@@ -1,12 +1,28 @@
 @tool
 @icon("res://addons/behaviour_toolkit/icons/BTComposite.svg")
 class_name BTComposite extends BTBehaviour
+## Basic Composite node for Behaviour Tree.
+##
+## By itself is not doing much but is aware of it's children. You can use it
+## to implement custom composite behaviours.
+
+
+# Connecting signal using @onready to omit the need to use super() call
+# in _ready() of extended nodes if they override _ready().
+@onready var __connect_child_order_changed: int = child_order_changed.connect(_on_child_order_changed)
 
 
 ## The leaves under the composite node.
 @onready var leaves: Array = get_children()
 
 
+func _on_child_order_changed() -> void:
+	if Engine.is_editor_hint():
+		return
+
+	leaves = get_children()
+
+
 func _get_configuration_warnings() -> PackedStringArray:
 	var warnings: Array = []
 
@@ -17,7 +33,7 @@ func _get_configuration_warnings() -> PackedStringArray:
 		warnings.append("BTComposite node must be a child of BTComposite or BTRoot node.")
 
 	if children.size() == 0:
-		warnings.append("BTComposite node must have at least one child.")
+		warnings.append("BTComposite node should have at least one child to work.")
 
 	if children.size() == 1:
 		warnings.append("BTComposite node should have more than one child.")

addons/behaviour_toolkit/behaviour_tree/bt_decorator.gd

@@ -1,10 +1,19 @@
 @tool
 @icon("res://addons/behaviour_toolkit/icons/BTDecorator.svg")
 class_name BTDecorator extends BTBehaviour
+## Basic Decorator node for Behaviour Tree.
+##
+## By itself is not doing much but is aware of it's children and holds reference
+## to its first child (index 0 child). You can use it to implement custom
+## decorators.
 
 
+# Connecting signal using @onready to omit the need to use super() call
+# in _ready() of extended nodes if they override _ready().
+@onready var __connect_child_order_changed: int = child_order_changed.connect(_on_child_order_changed)
+
 ## The leaf the decorator is decorating.
-@onready var leaf: BTBehaviour =  _get_leaf()
+@onready var leaf: BTBehaviour = _get_leaf()
 
 
 func _get_leaf() -> BTBehaviour:
@@ -14,6 +23,13 @@ func _get_leaf() -> BTBehaviour:
 	return get_child(0)
 
 
+func _on_child_order_changed() -> void:
+	if Engine.is_editor_hint():
+		return
+
+	leaf = _get_leaf()
+
+
 func _get_configuration_warnings() -> PackedStringArray:
 	var warnings: Array = []
 
@@ -26,8 +42,8 @@ func _get_configuration_warnings() -> PackedStringArray:
 	if children.size() == 0:
 		warnings.append("Decorator node should have a child.")
 	elif children.size() > 1:
-		warnings.append("Decorator node should have only one child.")
+		warnings.append("Decorator node has more than one child. Only the first child will be used, other sibilings will be ingored.")
 	elif not children[0] is BTBehaviour:
-		warnings.append("Decorator node should have a BTBehaviour node as a child.")
+		warnings.append("Decorator nodes first child must be a BTBehaviour node.")
 
 	return warnings

addons/behaviour_toolkit/behaviour_tree/bt_leaf.gd

@@ -1,6 +1,8 @@
 @tool
 @icon("res://addons/behaviour_toolkit/icons/BTLeaf.svg")
 class_name BTLeaf extends BTBehaviour
+## Basic Leaf node used as a base to model and write custom behaviours for
+## [BTRoot]
 
 
 func tick(_delta: float, _actor: Node, _blackboard: Blackboard) -> BTStatus:
@@ -15,8 +17,5 @@ func _get_configuration_warnings() -> PackedStringArray:
 
 	if not parent is BTBehaviour and not parent is BTRoot:
 		warnings.append("BTLeaf node must be a child of BTBehaviour or BTRoot node.")
-
-	if children.size() > 0:
-		warnings.append("BTLeaf node must not have any children.")
 
 	return warnings

addons/behaviour_toolkit/behaviour_tree/bt_root.gd

@@ -2,6 +2,8 @@
 @icon("res://addons/behaviour_toolkit/icons/BTRoot.svg")
 class_name BTRoot extends BehaviourToolkit
 ## Node used as a base parent (root) of a Behaviour Tree
+##
+## TODO
 
 
 enum ProcessType {
@@ -13,7 +15,7 @@ enum ProcessType {
 @export var autostart: bool = false
 
 ## Can be used to select if Behaviour Tree tick() is calculated on
-## rendering (IDLE) frame or physics (PHYSICS) frame. 
+## rendering (IDLE) frame or physics (PHYSICS) frame.
 ## [br]
 ## More info: [method Node._process] and [method Node._physics_process]
 @export var process_type: ProcessType = ProcessType.PHYSICS:
@@ -25,11 +27,29 @@ enum ProcessType {
 @export var blackboard: Blackboard
 
 
-var active: bool = false
+var active: bool = false:
+	set(value):
+		active = value
+		if value and entry_point != null:
+			_setup_processing()
+		else:
+			set_physics_process(false)
+			set_process(false)
+
 var current_status: BTBehaviour.BTStatus
 
 
-@onready var entry_point = get_child(0)
+# Connecting signal using @onready to omit the need to use super() call
+# in _ready() of extended nodes if they override _ready().
+@onready var __connect_child_order_changed: int = child_order_changed.connect(_on_child_order_changed)
+
+@onready var entry_point: BTBehaviour = get_entry_point()
+
+
+func _validate_property(property: Dictionary) -> void:
+	if property.name == "autostart" and get_parent() is FSMStateIntegratedBT:
+		autostart = false
+		property.usage = PROPERTY_USAGE_NO_EDITOR
 
 
 func _ready() -> void:
@@ -41,14 +61,31 @@ func _ready() -> void:
 
 	if blackboard == null:
 		blackboard = _create_local_blackboard()
-
-	if autostart:
+
+	if entry_point == null:
+		return
+	elif autostart:
 		active = true
 
-	if not process_type:
-		process_type = ProcessType.PHYSICS
 
-	_setup_processing()
+## Swap this [BTRoot] nodes current entry point with the provided one.
+## If root has no [BTBehaviour] as a child the provided one will be added.
+## [br][br]
+## Old behaviour nodes are freed and the new behaviour will be started on the
+## next [code]tick()[/code] callback call.
+func swap_entry_point(behaviour: BTBehaviour,
+	force_readable_name: bool = false, keep_groups: bool = false) -> void:
+
+	if keep_groups == true and entry_point != null:
+		for g in entry_point.get_groups():
+			if not behaviour.is_in_group(g):
+				behaviour.add_to_group(g, true)
+
+	if entry_point == null:
+		add_child(behaviour, force_readable_name)
+	else:
+		entry_point.queue_free()
+		add_child(behaviour, force_readable_name)
 
 
 func  _physics_process(delta: float) -> void:
@@ -60,6 +97,8 @@ func _process(delta: float) -> void:
 
 
 func _process_code(delta: float) -> void:
+	# TODO Would be nice to remove it in future and make use of set_process()
+	# and set_physics_process()
 	if not active:
 		return
 
@@ -73,21 +112,41 @@ func _create_local_blackboard() -> Blackboard:
 
 # Configures process type to use, if BTree is not active both are disabled.
 func _setup_processing() -> void:
+	if Engine.is_editor_hint():
+		set_physics_process(false)
+		set_process(false)
+		return
+
 	set_physics_process(process_type == ProcessType.PHYSICS)
 	set_process(process_type == ProcessType.IDLE)
 
 
+func get_entry_point() -> BTBehaviour:
+	var first_child := get_child(0)
+	if first_child is BTBehaviour:
+		return first_child
+	else:
+		return null
+
+
+func _on_child_order_changed() -> void:
+	if Engine.is_editor_hint():
+		return
+
+	entry_point = get_entry_point()
+
+
 func _get_configuration_warnings() -> PackedStringArray:
 	var warnings: Array = []
 
 	var children = get_children()
 
 	if children.size() == 0:
-		warnings.append("Behaviour Tree needs to have one Behaviour child.")
+		warnings.append("Behaviour Tree needs to have a Behaviour child to work.")
 	elif children.size() == 1:
 		if not children[0] is BTBehaviour:
-			warnings.append("The child of Behaviour Tree needs to be a Behaviour.")
+			warnings.append("The child of Behaviour Tree needs to be a BTBehaviour.")
 	elif children.size() > 1:
-		warnings.append("Behaviour Tree can have only one Behaviour child.")
+		warnings.append("Behaviour Tree has more than one child. Only the first child will be used, other sibilings will be ingored.")
 
 	return warnings

addons/behaviour_toolkit/behaviour_tree/composites/bt_integrated_fsm.gd

@@ -1,16 +1,49 @@
 @tool
 @icon("res://addons/behaviour_toolkit/icons/BTCompositeIntegration.svg")
 class_name BTIntegratedFSM extends BTComposite
+## [BTComposite] node of Behaviour Tree that can handle [FiniteStateMachine]
+##
+## When [BTIntegratedFSM] finds node of type [FiniteStateMachine] as it's first
+## child it starts the state machine and runs it on every
+## [code]tick()[/code] until the FSM node itself will stop returning
+## [enum BTBehaviour.BTStatus.RUNNING].
+## [br][br]
+## After FSM returns either of [enum BTBehaviour.BTStatus.SUCCESS] or
+## [enum BTBehaviour.BTStatus.FAILURE] then the final status of the FSM will be returned
+## as the final status of the [BTIntegratedFSM] node.
+## [br][br]
+## In case where [BTComposite] can't find [FiniteStateMachine] as it's first
+## child [enum BTBehaviour.BTStatus.FAILURE] will be returned.
 
 
-var state_machine: FiniteStateMachine = null
+## Default status in case [BTIntegratedFSM] will not find [FiniteStateMachine]
+## child as a first node.
+@export_enum("SUCCESS", "FAILURE") var default_status: String = "FAILURE":
+	set(value):
+		if value == "SUCCESS":
+			_default_status = BTStatus.SUCCESS
+		else:
+			_default_status = BTStatus.FAILURE
+
+
+var _default_status: BTStatus = BTStatus.FAILURE
+
+
+# Connecting signal using @onready to omit the need to use super() call
+# in _ready() of extended nodes if they override _ready().
+@onready var __connect_finite_state_machine_changed: int = child_order_changed.connect(_finite_state_machine_changed)
+
+@onready var state_machine: FiniteStateMachine = _get_machine()
 
 func _ready():
 	if not Engine.is_editor_hint():
 		state_machine = _get_machine()
 
 
 func tick(_delta: float, _actor: Node, _blackboard: Blackboard) -> BTStatus:
+	if state_machine == null:
+		return _default_status
+
 	if state_machine.active == false:
 		state_machine.start()
 
@@ -20,25 +53,56 @@ func tick(_delta: float, _actor: Node, _blackboard: Blackboard) -> BTStatus:
 	return state_machine.current_bt_status
 
 
+## Swap this composite nodes current state machine with the provided one.
+## If state has no [FiniteStateMachine] as a child the provided one will be added.
+## [br][br]
+## Old state machine is freed and the new machine will be started on the next
+## [code]tick()[/code] callback call.
+func swap_finite_state_machine(finite_state_machine: FiniteStateMachine, 
+	force_readable_name: bool = false, keep_groups: bool = false) -> void:
+
+	if keep_groups == true and state_machine != null:
+		for g in state_machine.get_groups():
+			if not finite_state_machine.is_in_group(g):
+				finite_state_machine.add_to_group(g, true)
+
+	if state_machine == null:
+		add_child(finite_state_machine, force_readable_name)
+	else:
+		state_machine.queue_free()
+		add_child(finite_state_machine, force_readable_name)
+
+
 func _get_machine() -> FiniteStateMachine:
 	if get_child_count() == 0:
 		return null
 	else:
-		return get_child(0)
+		if get_child(0) is FiniteStateMachine:
+			return get_child(0)
+
+	return null
+
+
+func _finite_state_machine_changed() -> void:
+	if Engine.is_editor_hint():
+		return
+
+	state_machine = _get_machine()
+	state_machine.autostart = false
 
 
 func _get_configuration_warnings():
 	var warnings: Array = []
 	var children = get_children()
 
 	if children.size() == 0:
-		warnings.append("BTIntegratedFSM must have a child node. The first child will be used as the state machine.")
+		warnings.append("BTIntegratedFSM should have a child node to work. The first child will be used as the state machine.")
 
 	if children.size() > 1:
-		warnings.append("BTIntegratedFSM can only have one child node. The first child will be used as the state machine.")
+		warnings.append("BTIntegratedFSM has more than one child node. Only the first child will be used as the state machine.")
 
 	if children.size() == 1:
 		if not children[0] is FiniteStateMachine:
-			warnings.append("BTIntegratedFSM's child node must be a FiniteStateMachine. The first child will be used as the state machine.")
+			warnings.append("BTIntegratedFSM's first child node must be a FiniteStateMachine. The first child will be used as the state machine.")
 
 	return warnings

addons/behaviour_toolkit/behaviour_tree/composites/bt_random.gd

@@ -11,7 +11,12 @@ var rng = RandomNumberGenerator.new()
 var active_leave: BTBehaviour
 
 
-func _ready():
+# Connecting signal using @onready to omit the need to use super() call
+# in _ready() of extended nodes if they override _ready().
+@onready var __connect_hash_seed: int = ready.connect(_hash_seed)
+
+
+func _hash_seed():
 	if use_seed:
 		rng.seed = hash(seed)