Update #47 - Singleplayer lag fixes

sources/main/java/com/carrotsearch/hppc/ObjectIdentityHashSet.java

@@ -0,0 +1,66 @@
+/*
+ * HPPC
+ *
+ * Copyright (C) 2010-2024 Carrot Search s.c. and contributors
+ * All rights reserved.
+ *
+ * Refer to the full license file "LICENSE.txt":
+ * https://github.com/carrotsearch/hppc/blob/master/LICENSE.txt
+ */
+package com.carrotsearch.hppc;
+
+import static com.carrotsearch.hppc.Containers.*;
+import static com.carrotsearch.hppc.HashContainers.*;
+
+/** A reference-equality (identity) hash set. */
+public class ObjectIdentityHashSet<KType> extends ObjectHashSet<KType> {
+  /** New instance with sane defaults. */
+  public ObjectIdentityHashSet() {
+    this(DEFAULT_EXPECTED_ELEMENTS, DEFAULT_LOAD_FACTOR);
+  }
+
+  /** New instance with sane defaults. */
+  public ObjectIdentityHashSet(int expectedElements) {
+    this(expectedElements, DEFAULT_LOAD_FACTOR);
+  }
+
+  /**
+   * New instance with the provided defaults.
+   *
+   * @param expectedElements The expected number of elements guaranteed not to cause a rehash
+   *     (inclusive).
+   * @param loadFactor The load factor for internal buffers. Insane load factors (zero, full
+   *     capacity) are rejected by {@link #verifyLoadFactor(double)}.
+   */
+  public ObjectIdentityHashSet(int expectedElements, double loadFactor) {
+    super(expectedElements, loadFactor);
+  }
+
+  /** New instance copying elements from another {@link ObjectContainer}. */
+  public ObjectIdentityHashSet(ObjectContainer<? extends KType> container) {
+    this(container.size());
+    addAll(container);
+  }
+
+  @Override
+  protected int hashKey(KType key) {
+    assert key != null; // Handled as a special case (empty slot marker).
+    return BitMixer.mixPhi(System.identityHashCode(key));
+  }
+
+  @Override
+  protected boolean equals(Object v1, Object v2) {
+    return v1 == v2;
+  }
+
+  /**
+   * Create a set from a variable number of arguments or an array of <code>KType</code>. The
+   * elements are copied from the argument to the internal buffer.
+   */
+  @SafeVarargs
+  public static <KType> ObjectIdentityHashSet<KType> from(KType... elements) {
+    final ObjectIdentityHashSet<KType> set = new ObjectIdentityHashSet<KType>(elements.length);
+    set.addAll(elements);
+    return set;
+  }
+}