hObjectPoolItem.cs

#region Copyright Notice & License Information
//
// hObjectPoolItem.cs
//
// Author:
//       Matthew Davey <matthew.davey@dotbunny.com>
//
// Copyright (c) 2013 dotBunny Inc. (http://www.dotbunny.com)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#endregion

using System.Collections;
using UnityEngine;

/// <summary>
/// A drop in implementation of the Hydrogen.Core.ObjectPoolItem. This is one possible way of setting up an 
/// ObjectPoolItem to handle spawning and despawning appropriately.
/// </summary>
/// <remarks>
/// Learn from it, make your own, as long as you extend from the base class
/// you still get the performance benefits.
/// </remarks>
[AddComponentMenu ("Hydrogen/Object Pool Item")]
public sealed class hObjectPoolItem : Hydrogen.Core.ObjectPoolItemBase
{
        /// <summary>
        /// Despawn gameObject after this number of seconds.
        /// </summary>
        /// <remarks>In seconds, use 0 to disable.</remarks>
        public float LifeTime;

        /// <summary>
        /// Despawn the gameObject safely after all particles have done their thing. 
        /// </summary>
        /// <remarks>If you are going to utilize this make sure that your function contains:
        /// hObjectPool.Instance.objectPools[poolID].DespawnImmediate(gameObject);</remarks>
        public override void DespawnSafely ()
        {
                StartCoroutine (WaitForParticles ());
        }

        /// <summary>
        /// Is the object idle, and therefore can be despawned organically?
        /// </summary>
        /// <returns>true</returns>
        /// <c>false</c>
        /// <remarks>This will only work on tracked spawned objects.</remarks>
        public override bool IsInactive ()
        {
                // A simple rigidbody check, otherwise no bueno
                return ParentPool.HasRigidbody && gameObject.rigidbody.IsSleeping ();
        }

        /// <summary>
        /// Raised when the object is 'despawned' back into the pool.
        /// </summary>
        /// <remarks>It does not set "active", you must handle that yourself.</remarks>
        public override void OnDespawned ()
        {
                // If our object has a rigidbody (cached check), make sure to zero its velocity.
                if (ParentPool.HasRigidbody)
                        gameObject.rigidbody.velocity = Vector3.zero;
        
                // Disable the gameObject
                gameObject.SetActive (false);
        }

        /// <summary>
        /// Raised when the object is 'spawned' from the pool.
        /// </summary>
        /// <remarks>It does not set "active", you must handle that yourself.</remarks>
        public override void OnSpawned ()
        {
                // Make sure our object is active please and thank you
                gameObject.SetActive (true);

                // If there is a LifeTime greater then 0, we set a timer to despawn
                if (LifeTime > 0)
                        StartCoroutine (DespawnTimer ());
        }

        /// <summary>
        /// Coroutine for despawning our gameObject after the timer value.
        /// </summary>
        IEnumerator DespawnTimer ()
        {
                yield return new WaitForSeconds (LifeTime);
                hObjectPool.Instance.Despawn (gameObject, PoolID);
        }

        /// <summary>
        /// Coroutine to wait for particles to be finished, then despawn gameObject.
        /// </summary>
        IEnumerator WaitForParticles ()
        {
                if (particleEmitter != null) {
                        yield return null;
                        yield return new WaitForEndOfFrame ();

                        while (particleEmitter.particleCount > 0) {
                                yield return null;
                        }
                        particleEmitter.emit = false;
                } else if (particleSystem != null) {
                        yield return new WaitForSeconds (particleSystem.startDelay + 0.25f);
                        while (particleSystem.IsAlive (true)) {
                                if (!particleSystem.gameObject.activeSelf) {
                                        particleSystem.Clear (true);
                                        yield break;
                                }
                                yield return null;
                        }
                }

                // Disable the gameObject
                gameObject.SetActive (false);

                // Immediately get rid of the object as we don't want any artifacts showing up
                hObjectPool.Instance.ObjectPools [PoolID].DespawnImmediate (gameObject);
        }
}