actors now always calls despawn() when being despawned

src/net/torvald/terrarum/gameactors/Actor.kt

@@ -51,10 +51,19 @@ abstract class Actor : Comparable<Actor>, Runnable {
         OVERLAY // screen overlay, not affected by lightmap
     }
 
-    abstract fun update(delta: Float)
+    open fun update(delta: Float) {
+        if (!canBeDespawned) flagDespawn = false // actively deny despawning request if cannot be despawned
+        if (canBeDespawned && flagDespawn) {
+            despawn()
+            despawned = true
+        }
+    }
 
     var actorValue = ActorValue(this)
     @Volatile var flagDespawn = false
+    @Transient var despawnHook: (Actor) -> Unit = {}
+    @Transient open val canBeDespawned = true
+    @Volatile internal var despawned = false
 
     override fun equals(other: Any?): Boolean {
         if (other == null) return false
@@ -84,6 +93,12 @@ abstract class Actor : Comparable<Actor>, Runnable {
         }
     }
 
+    open fun despawn() {
+        if (canBeDespawned) {
+            despawnHook(this)
+        }
+    }
+
     /**
      * ActorValue change event handler
      *

src/net/torvald/terrarum/gameactors/ActorWithBody.kt

@@ -518,6 +518,7 @@ open class ActorWithBody : Actor {
     }
 
     override fun update(delta: Float) {
+        super.update(delta)
 
         // re-scale hitbox
         // it's just much better to poll them than use perfectly-timed setter because latter simply cannot exist