Add project files.

Assets/Cryville/Common/Buffers/ListPool.cs

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+using System.Collections.Generic;
+
+namespace Cryville.Common.Buffers {
+	/// <summary>
+	/// A resource pool that allows reusing instances of lists of type <typeparamref name="T" />.
+	/// </summary>
+	/// <typeparam name="T">The item type of the lists in the pool.</typeparam>
+	public class ListPool<T> {
+		private class Bucket : ObjectPool<List<T>> {
+			readonly int _size;
+			public Bucket(int size, int capacity) : base(capacity) {
+				_size = size;
+			}
+			protected override List<T> Construct() {
+				return new List<T>(_size);
+			}
+		}
+		Bucket[] _buckets;
+		/// <summary>
+		/// Creates an instance of the <see cref="ListPool{T}" /> class with the default maximum list size and bucket capacity.
+		/// </summary>
+		public ListPool() : this(0x40000000, 256) { }
+		/// <summary>
+		/// Creates an instance of the <see cref="ListPool{T}" /> class.
+		/// </summary>
+		/// <param name="maxSize">The maximum size of the lists in the pool.</param>
+		/// <param name="capacityPerBucket">The capacity of each bucket. The pool groups lists of similar sizes into buckets for faster access.</param>
+		public ListPool(int maxSize, int capacityPerBucket) {
+			if (maxSize < 16) maxSize = 16;
+			int num = GetID(maxSize) + 1;
+			_buckets = new Bucket[num];
+			for (int i = 0; i < num; i++) {
+				_buckets[i] = new Bucket(GetSize(i), capacityPerBucket);
+			}
+		}
+		/// <summary>
+		/// Rents a list of the specified size from the pool. The size of the list must not be changed when it is rented.
+		/// </summary>
+		/// <param name="size">The size of the list.</param>
+		/// <returns>A <see cref="List{T}" /> of the specified size.</returns>
+		public List<T> Rent(int size) {
+			int len2 = size;
+			if (len2 < 16) len2 = 16;
+			var list = _buckets[GetID(len2)].Rent();
+			if (list.Count < size)
+				for (int i = list.Count; i < size; i++) list.Add(default(T));
+			else if (list.Count > size)
+				list.RemoveRange(size, list.Count - size);
+			return list;
+		}
+		/// <summary>
+		/// Returns a rented list to the pool.
+		/// </summary>
+		/// <param name="list">The list to return.</param>
+		public void Return(List<T> list) {
+			int len2 = list.Capacity;
+			if (len2 < 16) len2 = 16;
+			_buckets[GetID(len2)].Return(list);
+		}
+		static int GetID(int size) {
+			size -= 1;
+			size >>= 4;
+			int num = 0;
+			for (; size != 0; size >>= 1) num++;
+			return num;
+		}
+		static int GetSize(int id) {
+			return 0x10 << id;
+		}
+	}
+}