1 files changed, 115 insertions, 0 deletions
diff --git a/Ryujinx.Graphics.Vulkan/IdList.cs b/Ryujinx.Graphics.Vulkan/IdList.cs
new file mode 100644
index 00000000..d5a87a05
--- /dev/null
+++ b/Ryujinx.Graphics.Vulkan/IdList.cs
@@ -0,0 +1,115 @@
+using System.Collections.Generic;
+using System;
+
+namespace Ryujinx.Graphics.Vulkan
+{
+    class IdList<T> where T : class
+    {
+        private readonly List<T> _list;
+        private int _freeMin;
+
+        public IdList()
+        {
+            _list = new List<T>();
+            _freeMin = 0;
+        }
+
+        public int Add(T value)
+        {
+            int id;
+            int count = _list.Count;
+            id = _list.IndexOf(null, _freeMin);
+
+            if ((uint)id < (uint)count)
+            {
+                _list[id] = value;
+            }
+            else
+            {
+                id = count;
+                _freeMin = id + 1;
+
+                _list.Add(value);
+            }
+
+            return id + 1;
+        }
+
+        public void Remove(int id)
+        {
+            id--;
+
+            int count = _list.Count;
+
+            if ((uint)id >= (uint)count)
+            {
+                return;
+            }
+
+            if (id + 1 == count)
+            {
+                // Trim unused items.
+                int removeIndex = id;
+
+                while (removeIndex > 0 && _list[removeIndex - 1] == null)
+                {
+                    removeIndex--;
+                }
+
+                _list.RemoveRange(removeIndex, count - removeIndex);
+
+                if (_freeMin > removeIndex)
+                {
+                    _freeMin = removeIndex;
+                }
+            }
+            else
+            {
+                _list[id] = null;
+
+                if (_freeMin > id)
+                {
+                    _freeMin = id;
+                }
+            }
+        }
+
+        public bool TryGetValue(int id, out T value)
+        {
+            id--;
+
+            try
+            {
+                value = _list[id];
+                return value != null;
+            }
+            catch (ArgumentOutOfRangeException)
+            {
+                value = null;
+                return false;
+            }
+            catch (IndexOutOfRangeException)
+            {
+                value = null;
+                return false;
+            }
+        }
+
+        public void Clear()
+        {
+            _list.Clear();
+            _freeMin = 0;
+        }
+
+        public IEnumerator<T> GetEnumerator()
+        {
+            for (int i = 0; i < _list.Count; i++)
+            {
+                if (_list[i] != null)
+                {
+                    yield return _list[i];
+                }
+            }
+        }
+    }
+}
+\ No newline at end of file