Use different prefetch root for the base plan in BTPlayer and BTState

(cherry picked from commit ac2d734122)

blackboard/blackboard_plan.cpp

@@ -416,7 +416,7 @@ void BlackboardPlan::populate_blackboard(const Ref<Blackboard> &p_blackboard, bo
 		// Add a variable duplicate to the blackboard, optionally with NodePath prefetch.
 		BBVariable var = p.second.duplicate(true);
 		if (unlikely(do_prefetch && p.second.get_type() == Variant::NODE_PATH)) {
-			Node *prefetch_root = !is_derived() || is_derived_var_changed(p.first) ? p_prefetch_root : p_prefetch_root_for_base_plan;
+			Node *prefetch_root = !p_prefetch_root_for_base_plan || !is_derived() || is_derived_var_changed(p.first) ? p_prefetch_root : p_prefetch_root_for_base_plan;
 			Node *n = prefetch_root->get_node_or_null(p.second.get_value());
 			if (n != nullptr) {
 				var.set_value(n);

bt/bt_player.cpp

@@ -48,7 +48,7 @@ void BTPlayer::_load_tree() {
 	ERR_FAIL_COND_MSG(!behavior_tree->get_root_task().is_valid(), "BTPlayer: Initialization failed - behavior tree has no valid root task.");
 	Node *agent = GET_NODE(this, agent_node);
 	ERR_FAIL_NULL_MSG(agent, vformat("BTPlayer: Initialization failed - can't get agent with path '%s'.", agent_node));
-	Node *scene_root = scene_root_hint ? scene_root_hint : get_owner();
+	Node *scene_root = _get_scene_root();
 	ERR_FAIL_COND_MSG(scene_root == nullptr,
 			"BTPlayer: Initialization failed - unable to establish scene root. This is likely due to BTPlayer not being owned by a scene node. Check BTPlayer.set_scene_root_hint().");
 	bt_instance = behavior_tree->instantiate(agent, blackboard, this, scene_root);
@@ -184,7 +184,7 @@ void BTPlayer::_notification(int p_notification) {
 				}
 				if (blackboard_plan.is_valid()) {
 					// Don't overwrite existing blackboard values as they may be initialized from code.
-					blackboard_plan->populate_blackboard(blackboard, false, this);
+					blackboard_plan->populate_blackboard(blackboard, false, this, _get_scene_root());
 				}
 				if (behavior_tree.is_valid()) {
 					_load_tree();

bt/bt_player.h

@@ -50,6 +50,7 @@ private:
 
 	void _load_tree();
 	void _update_blackboard_plan();
+	_FORCE_INLINE_ Node *_get_scene_root() const { return scene_root_hint ? scene_root_hint : get_owner(); }
 
 protected:
 	static void _bind_methods();

bt/bt_state.cpp

@@ -65,10 +65,14 @@ void BTState::_update_blackboard_plan() {
 	}
 }
 
+Node *BTState::_get_prefetch_root_for_base_plan() {
+	return _get_scene_root();
+}
+
 void BTState::_setup() {
 	LimboState::_setup();
 	ERR_FAIL_COND_MSG(behavior_tree.is_null(), "BTState: BehaviorTree is not assigned.");
-	Node *scene_root = scene_root_hint ? scene_root_hint : get_owner();
+	Node *scene_root = _get_scene_root();
 	ERR_FAIL_NULL_MSG(scene_root, "BTState: Initialization failed - unable to establish scene root. This is likely due to BTState not being owned by a scene node. Check BTState.set_scene_root_hint().");
 	bt_instance = behavior_tree->instantiate(get_agent(), get_blackboard(), this, scene_root);
 	ERR_FAIL_COND_MSG(bt_instance.is_null(), "BTState: Initialization failed - failed to instantiate behavior tree.");

bt/bt_state.h

@@ -28,6 +28,8 @@ private:
 	Node *scene_root_hint = nullptr;
 	bool monitor_performance = false;
 
+	_FORCE_INLINE_ Node *_get_scene_root() const { return scene_root_hint ? scene_root_hint : get_owner(); }
+
 protected:
 	static void _bind_methods();
 
@@ -35,6 +37,7 @@ protected:
 
 	virtual bool _should_use_new_scope() const override { return true; }
 	virtual void _update_blackboard_plan() override;
+	virtual Node *_get_prefetch_root_for_base_plan() override;
 
 	virtual void _setup() override;
 	virtual void _exit() override;

hsm/limbo_state.cpp

@@ -33,6 +33,10 @@ void LimboState::set_blackboard_plan(const Ref<BlackboardPlan> &p_plan) {
 void LimboState::_update_blackboard_plan() {
 }
 
+Node *LimboState::_get_prefetch_root_for_base_plan() {
+	return this;
+}
+
 Ref<BlackboardPlan> LimboState::_get_parent_scope_plan() const {
 	BlackboardPlan *parent_plan = nullptr;
 	const LimboState *state = this;
@@ -96,7 +100,7 @@ void LimboState::_initialize(Node *p_agent, const Ref<Blackboard> &p_blackboard)
 	}
 	if (blackboard_plan.is_valid() && !blackboard_plan->is_empty()) {
 		// Don't overwrite existing blackboard values as they may be initialized from code.
-		blackboard_plan->populate_blackboard(blackboard, false, this);
+		blackboard_plan->populate_blackboard(blackboard, false, this, _get_prefetch_root_for_base_plan());
 	}
 
 	_setup();

hsm/limbo_state.h

@@ -54,6 +54,7 @@ protected:
 
 	virtual bool _should_use_new_scope() const { return blackboard_plan.is_valid() || is_root(); }
 	virtual void _update_blackboard_plan();
+	virtual Node *_get_prefetch_root_for_base_plan();
 
 	virtual void _setup();
 	virtual void _enter();