feat: npc unit will now deallocate itself when all npc members are killed

modules/wave_survival/npc_unit.cpp

@@ -8,6 +8,24 @@
 void NpcUnit::_bind_methods() {
 	BIND_HPROPERTY(Variant::OBJECT, patrol_path, PROPERTY_HINT_NODE_TYPE, "PatrolPath");
 	BIND_PROPERTY(Variant::FLOAT, patrol_speed);
+	BIND_HPROPERTY(Variant::OBJECT, region, PROPERTY_HINT_NODE_TYPE, "MapRegion");
+}
+
+void NpcUnit::on_npc_death() {
+	// remove any dead npcs from the list
+	// leaving their bodies as separate nodes part of the tree
+	for (EnemyBody *npc : this->npcs) {
+		if (npc->get_health()->get_health() <= 0) {
+			this->get_parent()->add_child(npc);
+			this->npcs.erase(npc);
+			break;
+		}
+	}
+	// remove unit from world once all npcs are dead
+	if (this->npcs.size() <= 0) {
+		this->set_region(nullptr); // de-register from region
+		this->queue_free();
+	}
 }
 
 void NpcUnit::on_npc_awareness_changed(bool value) {
@@ -22,9 +40,6 @@ void NpcUnit::child_added(Node *node) {
 		npc->set_unit(this);
 		Vector3 const offset{ npc->get_global_position() - get_global_position() };
 		npc->set_unit_offset({ offset.x, offset.z });
-		if (PlayerDetector * detector{ cast_to<PlayerDetector>(npc->get_node(NodePath("%PlayerDetector"))) }) {
-			detector->connect(PlayerDetector::sig_awareness_changed, callable_mp(this, &self_type::on_npc_awareness_changed));
-		}
 	}
 }
 
@@ -32,7 +47,19 @@ void NpcUnit::enter_tree() {
 	this->connect("child_entered_tree", callable_mp(this, &self_type::child_added));
 }
 
+void NpcUnit::ready() {
+	for (EnemyBody *npc : this->npcs) {
+		if (PlayerDetector * detector{ cast_to<PlayerDetector>(npc->get_node(NodePath("%PlayerDetector"))) }) {
+			detector->connect(PlayerDetector::sig_awareness_changed, callable_mp(this, &self_type::on_npc_awareness_changed));
+		}
+		if (HealthStatus * health{ npc->get_health() }) {
+			health->connect(HealthStatus::sig_death, callable_mp(this, &self_type::on_npc_death));
+		}
+	}
+}
+
 void NpcUnit::_notification(int what) {
+	// only run in-game
 	if (Engine::get_singleton()->is_editor_hint()) {
 		return;
 	}
@@ -42,6 +69,9 @@ void NpcUnit::_notification(int what) {
 		case NOTIFICATION_ENTER_TREE:
 			enter_tree();
 			return;
+		case NOTIFICATION_READY:
+			ready();
+			return;
 	}
 }
 
@@ -67,13 +97,17 @@ float NpcUnit::get_patrol_speed() const {
 
 void NpcUnit::set_region(MapRegion *region) {
 	if (this->region == region) {
-		return;
+		return; // don't re-register
 	}
 	if (this->region != nullptr) {
 		this->region->remove_unit(this);
+		this->region->disconnect(MapRegion::sig_phase_changed, callable_mp(this, &self_type::on_npc_awareness_changed));
 	}
 	this->region = region;
+	if (region != nullptr) {
 		region->register_unit(this);
+		region->connect(MapRegion::sig_phase_changed, callable_mp(this, &self_type::on_npc_awareness_changed));
+	}
 }
 
 MapRegion *NpcUnit::get_region() const {

modules/wave_survival/npc_unit.h

@@ -10,9 +10,11 @@ class MapRegion;
 class NpcUnit : public Node3D {
 	GDCLASS(NpcUnit, Node3D);
 	static void _bind_methods();
+	void on_npc_death();
 	void on_npc_awareness_changed(bool seen);
 	void child_added(Node *node);
 	void enter_tree();
+	void ready();
 
 protected:
 	void _notification(int what);