Initial commit: OpenRA game engine

Fork from OpenRA/OpenRA with one-click launch script (start-ra.cmd)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

OpenRA.Game/Primitives/Cache.cs

@@ -0,0 +1,50 @@
+#region Copyright & License Information
+/*
+ * Copyright (c) The OpenRA Developers and Contributors
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+
+namespace OpenRA.Primitives
+{
+	public class Cache<T, U> : IReadOnlyDictionary<T, U>
+	{
+		readonly Dictionary<T, U> cache;
+		readonly Func<T, U> loader;
+
+		public Cache(Func<T, U> loader, IEqualityComparer<T> c)
+		{
+			ArgumentNullException.ThrowIfNull(loader);
+
+			this.loader = loader;
+			cache = new Dictionary<T, U>(c);
+		}
+
+		public Cache(Func<T, U> loader)
+			: this(loader, EqualityComparer<T>.Default) { }
+
+		public U this[T key] => cache.GetOrAdd(key, loader);
+
+		public bool ContainsKey(T key) { return cache.ContainsKey(key); }
+		public bool TryGetValue(T key, out U value) { return cache.TryGetValue(key, out value); }
+		public int Count => cache.Count;
+		public void Clear() { cache.Clear(); }
+
+		public ICollection<T> Keys => cache.Keys;
+		public ICollection<U> Values => cache.Values;
+
+		IEnumerable<T> IReadOnlyDictionary<T, U>.Keys => cache.Keys;
+
+		IEnumerable<U> IReadOnlyDictionary<T, U>.Values => cache.Values;
+
+		public IEnumerator<KeyValuePair<T, U>> GetEnumerator() { return cache.GetEnumerator(); }
+		System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return GetEnumerator(); }
+	}
+}