using System;
using System.Collections.Generic;
using UnityEngine.Events;
namespace UnityEngine.Rendering
{
/// <summary>
/// Generic object pool.
/// </summary>
/// <typeparam name="T">Type of the object pool.</typeparam>
public class ObjectPool<T> where T : new()
{
readonly Stack<T> m_Stack = new Stack<T>();
readonly UnityAction<T> m_ActionOnGet;
readonly UnityAction<T> m_ActionOnRelease;
readonly bool m_CollectionCheck = true;
/// <summary>
/// Number of objects in the pool.
/// </summary>
public int countAll { get; private set; }
/// <summary>
/// Number of active objects in the pool.
/// </summary>
public int countActive { get { return countAll - countInactive; } }
/// <summary>
/// Number of inactive objects in the pool.
/// </summary>
public int countInactive { get { return m_Stack.Count; } }
/// <summary>
/// Constructor.
/// </summary>
/// <param name="actionOnGet">Action on get.</param>
/// <param name="actionOnRelease">Action on release.</param>
/// <param name="collectionCheck">True if collection integrity should be checked.</param>
public ObjectPool(UnityAction<T> actionOnGet, UnityAction<T> actionOnRelease, bool collectionCheck = true)
{
m_ActionOnGet = actionOnGet;
m_ActionOnRelease = actionOnRelease;
m_CollectionCheck = collectionCheck;
}
/// <summary>
/// Get an object from the pool.
/// </summary>
/// <returns>A new object from the pool.</returns>
public T Get()
{
T element;
if (m_Stack.Count == 0)
{
element = new T();
countAll++;
}
else
{
element = m_Stack.Pop();
}
if (m_ActionOnGet != null)
m_ActionOnGet(element);
return element;
}
/// <summary>
/// Pooled object.
/// </summary>
public struct PooledObject : IDisposable
{
readonly T m_ToReturn;
readonly ObjectPool<T> m_Pool;
internal PooledObject(T value, ObjectPool<T> pool)
{
m_ToReturn = value;
m_Pool = pool;
}
/// <summary>
/// Disposable pattern implementation.
/// </summary>
void IDisposable.Dispose() => m_Pool.Release(m_ToReturn);
}
/// <summary>
/// Get et new PooledObject.
/// </summary>
/// <param name="v">Output new typed object.</param>
/// <returns>New PooledObject</returns>
public PooledObject Get(out T v) => new PooledObject(v = Get(), this);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="element">Object to release.</param>
public void Release(T element)
{
#if UNITY_EDITOR // keep heavy checks in editor
if (m_CollectionCheck && m_Stack.Count > 0)
{
if (m_Stack.Contains(element))
Debug.LogError("Internal error. Trying to destroy object that is already released to pool.");
}
#endif
if (m_ActionOnRelease != null)
m_ActionOnRelease(element);
m_Stack.Push(element);
}
}
/// <summary>
/// Generic pool.
/// </summary>
/// <typeparam name="T">Type of the objects in the pull.</typeparam>
public static class GenericPool<T>
where T : new()
{
// Object pool to avoid allocations.
static readonly ObjectPool<T> s_Pool = new ObjectPool<T>(null, null);
/// <summary>
/// Get a new object.
/// </summary>
/// <returns>A new object from the pool.</returns>
public static T Get() => s_Pool.Get();
/// <summary>
/// Get a new PooledObject
/// </summary>
/// <param name="value">Output typed object.</param>
/// <returns>A new PooledObject.</returns>
public static ObjectPool<T>.PooledObject Get(out T value) => s_Pool.Get(out value);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="toRelease">Object to release.</param>
public static void Release(T toRelease) => s_Pool.Release(toRelease);
}
/// <summary>
/// Generic pool without collection checks.
/// This class is an alternative for the GenericPool for object that allocate memory when they are being compared.
/// It is the case for the CullingResult class from Unity, and because of this in HDRP HDCullingResults generates garbage whenever we use ==, .Equals or ReferenceEquals.
/// This pool doesn't do any of these comparison because we don't check if the stack already contains the element before releasing it.
/// </summary>
/// <typeparam name="T">Type of the objects in the pull.</typeparam>
public static class UnsafeGenericPool<T>
where T : new()
{
// Object pool to avoid allocations.
static readonly ObjectPool<T> s_Pool = new ObjectPool<T>(null, null, false);
/// <summary>
/// Get a new object.
/// </summary>
/// <returns>A new object from the pool.</returns>
public static T Get() => s_Pool.Get();
/// <summary>
/// Get a new PooledObject
/// </summary>
/// <param name="value">Output typed object.</param>
/// <returns>A new PooledObject.</returns>
public static ObjectPool<T>.PooledObject Get(out T value) => s_Pool.Get(out value);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="toRelease">Object to release.</param>
public static void Release(T toRelease) => s_Pool.Release(toRelease);
}
/// <summary>
/// List Pool.
/// </summary>
/// <typeparam name="T">Type of the objects in the pooled lists.</typeparam>
public static class ListPool<T>
{
// Object pool to avoid allocations.
static readonly ObjectPool<List<T>> s_Pool = new ObjectPool<List<T>>(null, l => l.Clear());
/// <summary>
/// Get a new List
/// </summary>
/// <returns>A new List</returns>
public static List<T> Get() => s_Pool.Get();
/// <summary>
/// Get a new list PooledObject.
/// </summary>
/// <param name="value">Output typed List.</param>
/// <returns>A new List PooledObject.</returns>
public static ObjectPool<List<T>>.PooledObject Get(out List<T> value) => s_Pool.Get(out value);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="toRelease">List to release.</param>
public static void Release(List<T> toRelease) => s_Pool.Release(toRelease);
}
/// <summary>
/// HashSet Pool.
/// </summary>
/// <typeparam name="T">Type of the objects in the pooled hashsets.</typeparam>
public static class HashSetPool<T>
{
// Object pool to avoid allocations.
static readonly ObjectPool<HashSet<T>> s_Pool = new ObjectPool<HashSet<T>>(null, l => l.Clear());
/// <summary>
/// Get a new HashSet
/// </summary>
/// <returns>A new HashSet</returns>
public static HashSet<T> Get() => s_Pool.Get();
/// <summary>
/// Get a new list PooledObject.
/// </summary>
/// <param name="value">Output typed HashSet.</param>
/// <returns>A new HashSet PooledObject.</returns>
public static ObjectPool<HashSet<T>>.PooledObject Get(out HashSet<T> value) => s_Pool.Get(out value);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="toRelease">hashSet to release.</param>
public static void Release(HashSet<T> toRelease) => s_Pool.Release(toRelease);
}
/// <summary>
/// Dictionary Pool.
/// </summary>
/// <typeparam name="TKey">Key type.</typeparam>
/// <typeparam name="TValue">Value type.</typeparam>
public static class DictionaryPool<TKey, TValue>
{
// Object pool to avoid allocations.
static readonly ObjectPool<Dictionary<TKey, TValue>> s_Pool
= new ObjectPool<Dictionary<TKey, TValue>>(null, l => l.Clear());
/// <summary>
/// Get a new Dictionary
/// </summary>
/// <returns>A new Dictionary</returns>
public static Dictionary<TKey, TValue> Get() => s_Pool.Get();
/// <summary>
/// Get a new dictionary PooledObject.
/// </summary>
/// <param name="value">Output typed Dictionary.</param>
/// <returns>A new Dictionary PooledObject.</returns>
public static ObjectPool<Dictionary<TKey, TValue>>.PooledObject Get(out Dictionary<TKey, TValue> value)
=> s_Pool.Get(out value);
/// <summary>
/// Release an object to the pool.
/// </summary>
/// <param name="toRelease">Dictionary to release.</param>
public static void Release(Dictionary<TKey, TValue> toRelease) => s_Pool.Release(toRelease);
}
}