Replace some Lists that used Base() with raw arrays

Game.Client/C_BaseAnimating.cs

@@ -283,7 +283,7 @@ public void Dispose() {
 	Vector3 BonePosition;
 	QAngle BoneAngles;
 	Handle<C_BaseAnimating> AttachedTo = new();
-	readonly List<Matrix3x4> CachedBoneData = [];
+	Matrix3x4[] CachedBoneData = [];
 
 	public void InvalidateBoneCache() {
 		MostRecentModelBoneCounter = ModelBoneCounter - 1;
@@ -533,7 +533,7 @@ public override bool SetupBones(Span<Matrix3x4> boneToWorldOut, int maxBones, in
 			AccumulatedBoneMask = 0;
 		}
 
-		int nBoneCount = CachedBoneData.Count;
+		int nBoneCount = CachedBoneData.Length;
 
 		AccumulatedBoneMask |= boneMask;
 
@@ -597,11 +597,11 @@ public override bool SetupBones(Span<Matrix3x4> boneToWorldOut, int maxBones, in
 		}
 
 		if (!boneToWorldOut.IsEmpty) {
-			if (maxBones >= CachedBoneData.Count) {
+			if (maxBones >= CachedBoneData.Length) {
 				memcpy(boneToWorldOut, CachedBoneData.AsSpan());
 			}
 			else {
-				Warning($"SetupBones: invalid bone array size ({maxBones} - needs {CachedBoneData.Count})\n");
+				Warning($"SetupBones: invalid bone array size ({maxBones} - needs {CachedBoneData.Length})\n");
 				return false;
 			}
 		}
@@ -992,12 +992,12 @@ private static void RecvProxy_Sequence(ref readonly RecvProxyData data, object i
 		Studio.DestroyBoneCache(HitboxBoneCacheHandle);
 		HitboxBoneCacheHandle = 0;
 
-		if (CachedBoneData.Count != hdr.NumBones()) {
-			CachedBoneData.SetSize(hdr.NumBones());
+		if (CachedBoneData.Length != hdr.NumBones()) {
+			CachedBoneData = new Matrix3x4[hdr.NumBones()];
 			for (i = 0; i < hdr.NumBones(); i++)
-				MathLib.SetIdentityMatrix(out CachedBoneData.AsSpan()[i]);
+				MathLib.SetIdentityMatrix(out CachedBoneData[i]);
 		}
-		BoneAccessor.Init(CachedBoneData.Base());
+		BoneAccessor.Init(CachedBoneData);
 
 		Ik = null;
 

Source.Common/BoneSetup.cs

@@ -1545,7 +1545,7 @@ public void CalcAutoplaySequences(Span<Vector3> pos, Span<Quaternion> q, TimeUni
 
 		ikContext?.AddAutoplayLocks(pos, q);
 
-		int count = studioHdr.GetAutoplayList(out Span<short> pList);
+		int count = studioHdr.GetAutoplayList(out ReadOnlySpan<short> pList);
 		for (int i = 0; i < count; i++) {
 			int sequenceIndex = pList[i];
 			MStudioSeqDesc seqdesc = studioHdr.Seqdesc(sequenceIndex);

Source.Common/DataCache/IMDLCache.cs

@@ -51,7 +51,7 @@ public interface IMDLCache
 	VCollide? GetVCollide(MDLHandle_t handle);
 	Memory<byte> GetAnimBlock(MDLHandle_t handle, int block);
 	VirtualModel? GetVirtualModel(MDLHandle_t handle);
-	Memory<short> GetAutoplayList(MDLHandle_t handle);
+	ReadOnlySpan<short> GetAutoplayList(MDLHandle_t handle);
 	VertexFileHeader? GetVertexData(MDLHandle_t handle);
 
 	void TouchAllData(MDLHandle_t handle);

Source.Common/Engine/IModelInfo.cs

@@ -61,7 +61,7 @@ public interface IVModelInfo
 	byte ComputeViewScreenFade(in Vector3 absOrigin, float radius, float fadeScale);
 
 	// both client and server
-	int GetAutoplayList(StudioHeader studioHdr, out Span<short> autoplayList);
+	int GetAutoplayList(StudioHeader studioHdr, out ReadOnlySpan<short> autoplayList);
 
 	// Gets a  terrain collision model (creates if necessary)
 	// NOTE: This may return NULL if the terrain model cannot be ized

Source.Common/Exts.cs

@@ -650,51 +650,7 @@ public static class BitVecExts
 	public static void Clear(this bool[] bools, int bit) => bools[bit] = false;
 }
 public static class ListExtensions
-{ // Thanks JamesHoux: https://stackoverflow.com/questions/4972951/listt-to-t-without-copying
-	delegate ref TField RefAccessor<TObj, TField>(TObj obj);
-	static class ArrayAccessor<T>
-	{
-		public static Func<List<T>, T[]> Getter;
-		public static RefAccessor<List<T>, int> GetCount;
-
-		static ArrayAccessor() {
-			var dm = new DynamicMethod("get", MethodAttributes.Static | MethodAttributes.Public, CallingConventions.Standard, typeof(T[]), [typeof(List<T>)], typeof(ArrayAccessor<T>), true);
-			var il = dm.GetILGenerator();
-			il.Emit(OpCodes.Ldarg_0); // Load List<T> argument
-			il.Emit(OpCodes.Ldfld, typeof(List<T>).GetField("_items", BindingFlags.NonPublic | BindingFlags.Instance)!); // Replace argument by field
-			il.Emit(OpCodes.Ret); // Return field
-			Getter = (Func<List<T>, T[]>)dm.CreateDelegate(typeof(Func<List<T>, T[]>));
-
-			dm = new DynamicMethod("getSize", MethodAttributes.Static | MethodAttributes.Public, CallingConventions.Standard, typeof(int).MakeByRefType(), [typeof(List<T>)], typeof(ArrayAccessor<T>), true);
-			il = dm.GetILGenerator();
-			il.Emit(OpCodes.Ldarg_0);
-			il.Emit(OpCodes.Ldflda, typeof(List<T>).GetField("_size", BindingFlags.NonPublic | BindingFlags.Instance)!);
-			il.Emit(OpCodes.Ret);
-			GetCount = (RefAccessor<List<T>, int>)dm.CreateDelegate(typeof(RefAccessor<List<T>, int>));
-		}
-	}
-
-	static class TempSwap<T>
-	{
-		public static readonly ThreadLocal<List<T>> List = new(() => []);
-	}
-
-	public static void Swap<T>(this List<T> a, List<T> b) {
-		var swap = TempSwap<T>.List.Value!;
-		swap.Clear();
-		swap.EnsureCapacity(a.Count);
-
-		a.Clear();
-		a.EnsureCapacity(b.Count);
-		b.Base().AsSpan()[..b.Count].CopyTo(a.Base());
-		a.CountForEdit() = b.Count;
-
-		b.Clear();
-		b.EnsureCapacity(swap.Count);
-		swap.Base().AsSpan()[..swap.Count].CopyTo(b.Base());
-		b.CountForEdit() = swap.Count;
-	}
-
+{
 	public static nint Find<T>(this List<T> list, T? value) {
 		for (int i = 0, c = list.Count; i < c; i++) {
 			T? at = list[i];
@@ -710,14 +666,6 @@ public static nint Find<T>(this List<T> list, T? value) {
 		}
 		return -1;
 	}
-
-	public static T[] Base<T>(this List<T> list) {
-		return ArrayAccessor<T>.Getter(list);
-	}
-
-	public static ref int CountForEdit<T>(this List<T> list) {
-		return ref ArrayAccessor<T>.GetCount(list);
-	}
 }
 public static class ClassUtils
 {

Source.Common/IStudioRender.cs

@@ -2,6 +2,7 @@
 using Source.Common.Engine;
 using Source.Common.MaterialSystem;
 using Source.Common.Mathematics;
+using Source.Common.Utilities;
 
 using System.Numerics;
 
@@ -100,8 +101,8 @@ public interface IStudioRender {
 	bool LoadModel(StudioHeader studioHDR, Memory<byte> vtxData, StudioHWData hardwareData);
 	void UnloadModel(StudioHWData hardwareData);
 
-	int GetMaterialList(StudioHeader studioHDR, Span<IMaterial> materials);
-	int GetMaterialListFromBodyAndSkin(MDLHandle_t studio, int skin, int body, Span<IMaterial> outputMaterials);
+	void GetMaterialList(StudioHeader studioHDR, ref SpanList<IMaterial> materials);
+	void GetMaterialListFromBodyAndSkin(MDLHandle_t studio, int skin, int body, ref SpanList<IMaterial> outputMaterials);
 	Span<Matrix3x4> LockBoneMatrices(int boneCount);
 	void UnlockBoneMatrices();
 	void LockFlexWeights(int weightCount, out Span<float> flexWeights);

Source.Common/Studio.cs

@@ -343,14 +343,14 @@ public VirtualGroup AnimGroup(int animation) {
 
 	public readonly object Lock = new();
 
-	public readonly List<VirtualSequence> Seq = [];
-	public readonly List<VirtualGeneric> Anim = [];
-	public readonly List<VirtualGeneric> Attachment = [];
-	public readonly List<VirtualGeneric> Pose = [];
+	public List<VirtualSequence> Seq = [];
+	public List<VirtualGeneric> Anim = [];
+	public List<VirtualGeneric> Attachment = [];
+	public List<VirtualGeneric> Pose = [];
 	public readonly List<VirtualGroup> Group = [];
-	public readonly List<VirtualGeneric> Node = [];
-	public readonly List<VirtualGeneric> IKLock = [];
-	public readonly List<short> AutoplaySequences = [];
+	public List<VirtualGeneric> Node = [];
+	public List<VirtualGeneric> IKLock = [];
+	public short[] AutoplaySequences = [];
 }
 
 public enum StudioMeshGroupFlags
@@ -2038,7 +2038,7 @@ public class StudioHdr
 	public Span<MStudioBone> Bones() => studioHdr.Bones();
 
 
-	readonly List<StudioHeader?> StudioHdrCache = [];
+	StudioHeader?[] StudioHdrCache = [];
 
 	public StudioHdrFlags Flags() => studioHdr!.Flags;
 	public AnonymousSafeFieldPointer<int> FrameUnlockCounterPtr;
@@ -2048,7 +2048,7 @@ public void Init(StudioHeader? studioHdr, IMDLCache mdlcache) {
 		this.studioHdr = studioHdr;
 
 		this.vModel = null;
-		StudioHdrCache.Clear();
+		StudioHdrCache = [];
 
 		if (this.studioHdr == null)
 			return;
@@ -2088,10 +2088,7 @@ public bool SequencesAvailable() {
 	private VirtualModel? ResetVModel(VirtualModel? virtualModel) {
 		if (virtualModel != null) {
 			vModel = virtualModel;
-			StudioHdrCache!.EnsureCountDefault(vModel.Group.Count());
-
-			for (int i = 0; i < StudioHdrCache.Count; i++)
-				StudioHdrCache[i] = null!;
+			StudioHdrCache = new StudioHeader?[vModel.Group.Count()];
 
 			return vModel;
 		}
@@ -2120,13 +2117,13 @@ public int RemapSeqBone(int sequence, int localBone) {
 			lock (FrameUnlockCounterMutex) {
 				if (FrameUnlockCounterPtr.Get() != FrameUnlockCounter) // i.e., this thread got the mutex
 				{
-					memcreset(StudioHdrCache.Base());
+					memcreset<StudioHeader>(StudioHdrCache);
 					FrameUnlockCounter = FrameUnlockCounterPtr.Get();
 				}
 			}
 		}
 
-		if (!StudioHdrCache.IsValidIndex(i)) {
+		if ((uint)i >= (uint)StudioHdrCache.Length) {
 			ReadOnlySpan<char> name = (this.studioHdr != null) ? this.studioHdr.GetName() : "<<null>>";
 			Debugger.Break();
 			return this.studioHdr; // return something known to probably exist, certainly things will be messed up, but hopefully not crash before the warning is noticed
@@ -2674,7 +2671,7 @@ internal int RelativeSeq(int baseseq, int relseq) {
 		return group.MasterSeq[relseq];
 	}
 
-	public int GetAutoplayList(out Span<short> pList) {
+	public int GetAutoplayList(out ReadOnlySpan<short> pList) {
 		return studioHdr!.GetAutoplayList(out pList);
 	}
 
@@ -3181,7 +3178,7 @@ public ref byte LocalTransition(int i) {
 	}
 
 
-	public int GetAutoplayList(out Span<short> pList) {
+	public int GetAutoplayList(out ReadOnlySpan<short> pList) {
 		return modelinfo.GetAutoplayList(this, out pList);
 	}
 
@@ -3221,18 +3218,6 @@ public int CountAutoplaySequences() {
 		return count;
 	}
 
-	public void CopyAutoplaySequences(ref Memory<short> autoplaySequenceList, int outCount) {
-		int outIndex = 0;
-		for (int i = 0; i < GetNumSeq() && outIndex < outCount; i++) {
-			MStudioSeqDesc seqdesc = Seqdesc(i);
-			if ((seqdesc.Flags & StudioAnimSeqFlags.Autoplay) != 0) {
-				autoplaySequenceList.Span[outIndex] = (short)i;
-				outIndex++;
-			}
-		}
-		autoplaySequenceList = autoplaySequenceList[..outIndex];
-	}
-
 	public int CopyAutoplaySequences(Span<short> autoplaySequenceList, int outCount) {
 		int outIndex = 0;
 		for (int i = 0; i < GetNumSeq() && outIndex < outCount; i++) {

Source.Common/StudioVirtualModel.cs

@@ -56,16 +56,8 @@ public void Dispose() {
 		private int LookupIndex;
 	}
 
-	void BeginTemporaryCopyList<T>(List<T> source, out List<T> dest) {
-		dest = ListPool<T>.Shared.Alloc();
-		dest.Clear();
-		dest.CountForEdit() = source.Count;
-		source.AsSpan().CopyTo(dest.AsSpan());
-	}
-	void EndTemporaryCopyList<T>(List<T> source, List<T> dest) {
-		source.Swap(dest);
-		ListPool<T>.Shared.Free(dest);
-	}
+	void BeginTemporaryCopyList<T>(List<T> source, out List<T> dest) => dest = new List<T>(source);
+	void EndTemporaryCopyList<T>(ref List<T> source, List<T> dest) => source = dest;
 
 	public void AppendSequences(int group, StudioHeader studioHdr) {
 		lock (Lock) {
@@ -123,7 +115,7 @@ public void AppendSequences(int group, StudioHeader studioHdr) {
 						GetSeqTable()[s1.Hash(invariant: false)] = (short)j;
 					}
 				}
-				EndTemporaryCopyList(Seq, seq);
+				EndTemporaryCopyList(ref Seq, seq);
 			}
 		}
 	}
@@ -171,7 +163,7 @@ public void AppendAnimations(int group, StudioHeader studioHdr) {
 					}
 				}
 
-				EndTemporaryCopyList(Anim, anim);
+				EndTemporaryCopyList(ref Anim, anim);
 			}
 		}
 	}
@@ -224,7 +216,7 @@ public void AppendAttachments(int group, StudioHeader studioHdr) {
 				Group[group].MasterAttachment[j] = k;
 			}
 
-			EndTemporaryCopyList(Attachment, attachment);
+			EndTemporaryCopyList(ref Attachment, attachment);
 		}
 	}
 	public void AppendPoseParameters(int group, StudioHeader studioHdr) {
@@ -264,7 +256,7 @@ public void AppendPoseParameters(int group, StudioHeader studioHdr) {
 				Group[group].MasterPose[j] = k;
 			}
 
-			EndTemporaryCopyList(Pose, pose);
+			EndTemporaryCopyList(ref Pose, pose);
 		}
 	}
 	public void AppendBonemap(int group, StudioHeader studioHdr) {
@@ -339,7 +331,7 @@ public void AppendNodes(int group, StudioHeader studioHdr) {
 				Group[group].MasterNode[j] = k;
 			}
 
-			EndTemporaryCopyList(Node, node);
+			EndTemporaryCopyList(ref Node, node);
 		}
 	}
 
@@ -367,7 +359,7 @@ public void AppendIKLocks(int group, StudioHeader studioHDR) {
 				}
 			}
 
-			EndTemporaryCopyList(IKLock, iklock);
+			EndTemporaryCopyList(ref IKLock, iklock);
 		}
 	}
 
@@ -426,7 +418,8 @@ public void AppendModels(int group, StudioHeader studioHdr) {
 	}
 	public void UpdateAutoplaySequences(StudioHeader studioHdr) {
 		int autoplayCount = studioHdr.CountAutoplaySequences();
-		AutoplaySequences.SetCount(autoplayCount);
-		studioHdr.CopyAutoplaySequences(AutoplaySequences.Base().AsSpan(), autoplayCount);
+		if (AutoplaySequences.Length != autoplayCount)
+			AutoplaySequences = new short[autoplayCount];
+		studioHdr.CopyAutoplaySequences(AutoplaySequences, autoplayCount);
 	}
 }

Source.Common/Utilities/SpanList.cs

@@ -0,0 +1,26 @@
+namespace Source.Common.Utilities;
+
+/// <summary>
+/// <see cref="List{T}"/> style of operations on fixed/pre-allocated arrays.
+/// </summary>
+public ref struct SpanList<T>(Span<T> items)
+{
+	readonly Span<T> Items = items;
+	int Used;
+
+	public readonly int Count => Used;
+	public readonly int Capacity => Items.Length;
+
+	public readonly ref T this[int index] => ref Items[..Used][index];
+
+	public void Add(in T value) => Items[Used++] = value;
+
+	public void RemoveAt(int index) {
+		Items[(index + 1)..Used].CopyTo(Items[index..]);
+		Used--;
+	}
+
+	public void Clear() => Used = 0;
+
+	public readonly Span<T> AsSpan() => Items[..Used];
+}