+ astar project

1 files changed, 318 insertions, 0 deletions

diff --git a/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Core/Collections/NativeCircularBuffer.cs b/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Core/Collections/NativeCircularBuffer.cs
new file mode 100644
index 0000000..6f4eb4a
--- /dev/null
+++ b/Other/AstarPathfindingDemo/Packages/com.arongranberg.astar/Core/Collections/NativeCircularBuffer.cs
@@ -0,0 +1,318 @@
+using System.Collections;
+using System.Collections.Generic;
+using Unity.Collections;
+using Unity.Collections.LowLevel.Unsafe;
+using Unity.Mathematics;
+using UnityEngine.Assertions;
+
+namespace Pathfinding.Util {
+	/// <summary>
+	/// Implements an efficient circular buffer that can be appended to in both directions.
+	///
+	/// See: <see cref="CircularBuffer"/>
+	/// </summary>
+	public struct NativeCircularBuffer<T> : IReadOnlyList<T>, IReadOnlyCollection<T> where T : unmanaged {
+		[NativeDisableUnsafePtrRestriction]
+		internal unsafe T* data;
+		internal int head;
+		int length;
+		/// <summary>Capacity of the allocation minus 1. Invariant: (a power of two) minus 1</summary>
+		int capacityMask;
+
+		/// <summary>The allocator used to create the internal buffer.</summary>
+		public AllocatorManager.AllocatorHandle Allocator;
+		/// <summary>Number of items in the buffer</summary>
+		public readonly int Length => length;
+		/// <summary>Absolute index of the first item in the buffer, may be negative or greater than <see cref="Length"/></summary>
+		public readonly int AbsoluteStartIndex => head;
+		/// <summary>Absolute index of the last item in the buffer, may be negative or greater than <see cref="Length"/></summary>
+		public readonly int AbsoluteEndIndex => head + length - 1;
+
+		/// <summary>First item in the buffer throws if the buffer is empty</summary>
+		public readonly ref T First {
+			[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+			get {
+				unsafe {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+					if (length == 0) throw new System.InvalidOperationException();
+#endif
+					return ref data[head & capacityMask];
+				}
+			}
+		}
+
+		/// <summary>Last item in the buffer, throws if the buffer is empty</summary>
+		public readonly ref T Last {
+			[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+			get {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+				if (length == 0) throw new System.InvalidOperationException();
+#endif
+				unsafe { return ref data[(head+length-1) & capacityMask]; }
+			}
+		}
+
+		readonly int IReadOnlyCollection<T>.Count => Length;
+
+		public readonly bool IsCreated {
+			get {
+				unsafe {
+					return data != null;
+				}
+			}
+		}
+
+		/// <summary>Create a new empty buffer</summary>
+
+		public NativeCircularBuffer(AllocatorManager.AllocatorHandle allocator) {
+			unsafe {
+				data = null;
+			}
+			Allocator = allocator;
+			capacityMask = -1;
+			head = 0;
+			length = 0;
+		}
+
+		/// <summary>Create a new buffer with the given capacity</summary>
+		public NativeCircularBuffer(int initialCapacity, AllocatorManager.AllocatorHandle allocator) {
+			initialCapacity = math.ceilpow2(initialCapacity);
+			unsafe {
+				data = AllocatorManager.Allocate<T>(allocator, initialCapacity);
+				capacityMask = initialCapacity - 1;
+			}
+			Allocator = allocator;
+			head = 0;
+			length = 0;
+		}
+
+		unsafe public NativeCircularBuffer(CircularBuffer<T> buffer, out ulong gcHandle) : this(buffer.data, buffer.head, buffer.Length, out gcHandle) {}
+
+		unsafe public NativeCircularBuffer(T[] data, int head, int length, out ulong gcHandle) {
+			Assert.IsTrue((data.Length & (data.Length - 1)) == 0);
+			Assert.IsTrue(length <= data.Length);
+			unsafe {
+				this.data = (T*)UnsafeUtility.PinGCArrayAndGetDataAddress(data, out gcHandle);
+			}
+			this.capacityMask = data.Length - 1;
+			this.head = head;
+			this.length = length;
+			Allocator = Unity.Collections.Allocator.None;
+		}
+
+		/// <summary>Resets the buffer's length to zero. Does not clear the current allocation</summary>
+		public void Clear () {
+			length = 0;
+			head = 0;
+		}
+
+		/// <summary>Appends a list of items to the end of the buffer</summary>
+		public void AddRange (List<T> items) {
+			// TODO: Can be optimized
+			for (int i = 0; i < items.Count; i++) PushEnd(items[i]);
+		}
+
+		/// <summary>Pushes a new item to the start of the buffer</summary>
+		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+		public void PushStart (T item) {
+			if (length > capacityMask) Grow();
+			length += 1;
+			head -= 1;
+			this[0] = item;
+		}
+
+		/// <summary>Pushes a new item to the end of the buffer</summary>
+		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+		public void PushEnd (T item) {
+			if (length > capacityMask) Grow();
+			length += 1;
+			this[length-1] = item;
+		}
+
+		/// <summary>Pushes a new item to the start or the end of the buffer</summary>
+		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+		public void Push (bool toStart, T item) {
+			if (toStart) PushStart(item);
+			else PushEnd(item);
+		}
+
+		/// <summary>Removes and returns the first element</summary>
+		public T PopStart () {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+			if (length == 0) throw new System.InvalidOperationException();
+#endif
+			var r = this[0];
+			head++;
+			length--;
+			return r;
+		}
+
+		/// <summary>Removes and returns the last element</summary>
+		public T PopEnd () {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+			if (length == 0) throw new System.InvalidOperationException();
+#endif
+			var r = this[length-1];
+			length--;
+			return r;
+		}
+
+		/// <summary>Pops either from the start or from the end of the buffer</summary>
+		public T Pop (bool fromStart) {
+			if (fromStart) return PopStart();
+			else return PopEnd();
+		}
+
+		/// <summary>Return either the first element or the last element</summary>
+		public readonly T GetBoundaryValue (bool start) {
+			return start ? GetAbsolute(AbsoluteStartIndex) : GetAbsolute(AbsoluteEndIndex);
+		}
+
+		/// <summary>Lowers the length of the buffer to the given value, and does nothing if the given value is greater or equal to the current length</summary>
+
+		public void TrimTo (int length) {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+			if (length < 0) throw new System.ArgumentOutOfRangeException();
+#endif
+			this.length = math.min(this.length, length);
+		}
+
+		/// <summary>Removes toRemove items from the buffer, starting at startIndex, and then inserts the toInsert items at startIndex</summary>
+
+		public void Splice (int startIndex, int toRemove, List<T> toInsert) {
+			SpliceAbsolute(startIndex + head, toRemove, toInsert);
+		}
+
+		/// <summary>Like <see cref="Splice"/>, but startIndex is an absolute index</summary>
+
+		public void SpliceAbsolute (int startIndex, int toRemove, List<T> toInsert) {
+			SpliceUninitializedAbsolute(startIndex, toRemove, toInsert.Count);
+			unsafe {
+				for (int i = 0; i < toInsert.Count; i++) data[(startIndex + i) & capacityMask] = toInsert[i];
+			}
+		}
+
+		/// <summary>Like <see cref="Splice"/>, but the newly inserted items are left in an uninitialized state</summary>
+		public void SpliceUninitialized (int startIndex, int toRemove, int toInsert) {
+			SpliceUninitializedAbsolute(startIndex + head, toRemove, toInsert);
+		}
+
+		/// <summary>Like <see cref="SpliceUninitialized"/>, but startIndex is an absolute index</summary>
+		public void SpliceUninitializedAbsolute (int startIndex, int toRemove, int toInsert) {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+			if (startIndex - head < 0 || startIndex + toRemove - head > length) throw new System.ArgumentOutOfRangeException();
+#endif
+			var itemsToAdd = toInsert - toRemove;
+			while (this.length + itemsToAdd > capacityMask + 1) Grow();
+
+			// move items [startIndex+length .. end] itemsToAdd steps forward in the array
+			MoveAbsolute(startIndex + toRemove, AbsoluteEndIndex, itemsToAdd);
+			this.length += itemsToAdd;
+		}
+
+		void MoveAbsolute (int startIndex, int endIndex, int deltaIndex) {
+			unsafe {
+				if (deltaIndex > 0) {
+					for (int i = endIndex; i >= startIndex; i--) data[(i+deltaIndex) & capacityMask] = data[i & capacityMask];
+				} else if (deltaIndex < 0) {
+					for (int i = startIndex; i <= endIndex; i++) data[(i+deltaIndex) & capacityMask] = data[i & capacityMask];
+				}
+			}
+		}
+
+		/// <summary>Indexes the buffer, with index 0 being the first element</summary>
+		public T this[int index] {
+			[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+			readonly get {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+				if ((uint)index >= length) throw new System.ArgumentOutOfRangeException();
+#endif
+				unsafe {
+					return data[(index+head) & capacityMask];
+				}
+			}
+			[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+			set {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+				if ((uint)index >= length) throw new System.ArgumentOutOfRangeException();
+#endif
+				unsafe {
+					data[(index+head) & capacityMask] = value;
+				}
+			}
+		}
+
+		/// <summary>
+		/// Indexes the buffer using absolute indices.
+		/// When pushing to and popping from the buffer, the absolute indices do not change.
+		/// So e.g. after doing PushStart(x) on an empty buffer, GetAbsolute(-1) will get the newly pushed element.
+		/// </summary>
+		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.AggressiveInlining)]
+		public readonly T GetAbsolute (int index) {
+#if ENABLE_UNITY_COLLECTIONS_CHECKS
+			if ((uint)(index - head) >= length) throw new System.ArgumentOutOfRangeException();
+#endif
+			unsafe {
+				return data[index & capacityMask];
+			}
+		}
+
+		[System.Runtime.CompilerServices.MethodImpl(System.Runtime.CompilerServices.MethodImplOptions.NoInlining)]
+		void Grow () {
+			unsafe {
+				// Note: Will always be a power of 2 since capacity is a power of 2
+				var capacity = capacityMask + 1;
+				var newCapacity = math.max(4, capacity*2);
+				var newData = AllocatorManager.Allocate<T>(this.Allocator, newCapacity);
+				if (data != null) {
+					var inOrderItems = capacity - (head & capacityMask);
+					UnsafeUtility.MemCpy(newData + (head & (newCapacity - 1)), data + (head & capacityMask), inOrderItems * sizeof(T));
+					var wraparoundItems = length - inOrderItems;
+					if (wraparoundItems > 0) {
+						UnsafeUtility.MemCpy(newData + ((head + inOrderItems) & (newCapacity - 1)), data, wraparoundItems * sizeof(T));
+					}
+					AllocatorManager.Free(Allocator, data);
+				}
+				capacityMask = newCapacity - 1;
+				data = newData;
+			}
+		}
+
+		/// <summary>Releases the unmanaged memory held by this container</summary>
+		public void Dispose () {
+			capacityMask = -1;
+			length = 0;
+			head = 0;
+			unsafe {
+				AllocatorManager.Free(Allocator, data);
+				data = null;
+			}
+		}
+
+		public IEnumerator<T> GetEnumerator () {
+			for (int i = 0; i < length; i++) {
+				yield return this[i];
+			}
+		}
+
+		IEnumerator IEnumerable.GetEnumerator () {
+			for (int i = 0; i < length; i++) {
+				yield return this[i];
+			}
+		}
+
+		public NativeCircularBuffer<T> Clone () {
+			unsafe {
+				var newData = AllocatorManager.Allocate<T>(this.Allocator, capacityMask + 1);
+				UnsafeUtility.MemCpy(newData, data, length * sizeof(T));
+				return new NativeCircularBuffer<T> {
+						   data = newData,
+						   head = head,
+						   length = length,
+						   capacityMask = capacityMask,
+						   Allocator = this.Allocator
+				};
+			}
+		}
+	}
+}