/// <summary>
/// Instantiate one GameObject from prefab and add it to the queue
/// </summary>
/// <param name="queue">PoolInstance queue</param>
/// <param name="prefab">Prefab to be instantiated</param>
private void InstantiateAndQueue(Queue <PoolInstance> queue, GameObject prefab)
{
// Spawn the game object and deactivate it
GameObject obj = Instantiate(prefab);
obj.SetActive(false);
// Check if PoolInstance script has been added, otherwise add it by code
PoolInstance instance = obj.GetComponent <PoolInstance>();
if (instance == null)
{
instance = obj.AddComponent <PoolInstance>();
}
// Set reference to the pool and original prefabs
instance.Pool = this;
instance.OriginalPrefab = prefab;
// Despawn it
Despawn(instance);
// Add to queue
queue.Enqueue(instance);
}
/// <summary>
/// Despawn this game object back to the object pool.
/// Only successful if it contains PoolInstance and it's original prefab currently being pooled.
/// </summary>
/// <param name="obj">GameObject to despawn back to object pool</param>
public void Despawn(GameObject obj)
{
if (obj == null)
{
return;
}
PoolInstance poolInstance = obj.GetComponent <PoolInstance>();
Despawn(poolInstance);
}
/// <summary>
/// Despawns this game object back to the object pool.
/// Only successful if its original prefab is currently being pooled.
/// </summary>
/// <param name="instance">PoolInstance whose GameObject will be despawned back to object pool</param>
public void Despawn(PoolInstance instance)
{
if (instance == null)
{
return;
}
if (!pools.ContainsKey(instance.OriginalPrefab))
{
return;
}
// Disable game object
instance.gameObject.SetActive(false);
// Call the onDespawned event on PoolInstance
instance.OnDespawned();
// Queue it back to pool
pools[instance.OriginalPrefab].poolQueue.Enqueue(instance);
}
/// <summary>
/// Try to spawn from the object pool with a prefab reference
/// </summary>
/// <param name="prefab">Same prefab reference on the ObjectPooler</param>
/// <returns>A GameObject if it's available on the pool, null if not available</returns>
public GameObject TryToSpawn(GameObject prefab)
{
if (prefab == null)
{
return(null);
}
if (!pools.ContainsKey(prefab))
{
return(null);
}
// If the pool is empty, check if we can instantiate more
if (pools[prefab].poolQueue.Count <= 0)
{
if (pools[prefab].poolInfo.autoIncreasePool)
{
// Instantiate more to the pool
InstantiateAndQueue(pools[prefab].poolQueue, prefab);
return(TryToSpawn(prefab));
}
else
{
// We can't instantiate anymore
return(null);
}
}
// Dequeue it and activate the game object
PoolInstance instance = pools[prefab].poolQueue.Dequeue();
GameObject obj = instance.gameObject;
obj.SetActive(true);
// Invoke the onSpawned event on PoolInstance
instance.OnSpawned();
return(obj);
}
