Introduce TargetString to eliminate text GC.

Assets/Cryville/Common/Buffers/TargetString.cs

@@ -0,0 +1,120 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+
+namespace Cryville.Common.Buffers {
+	/// <summary>
+	/// An auto-resized <see cref="char" /> array as a variable-length string used as a target that is modified frequently.
+	/// </summary>
+	public class TargetString : IEnumerable<char> {
+		public event Action OnUpdate;
+		char[] _arr;
+		bool _invalidated;
+		/// <summary>
+		/// Creates an instance of the <see cref="TargetString" /> class with a capacity of 16.
+		/// </summary>
+		public TargetString() : this(16) { }
+		/// <summary>
+		/// Creates an instance of the <see cref="TargetString" /> class.
+		/// </summary>
+		/// <param name="capacity">The initial capacity of the string.</param>
+		public TargetString(int capacity) {
+			_arr = new char[capacity];
+		}
+		/// <summary>
+		/// Gets or sets one of the characters in the string.
+		/// </summary>
+		/// <param name="index">The zero-based index of the character.</param>
+		/// <returns>The character at the given index.</returns>
+		/// <exception cref="ArgumentOutOfRangeException"><paramref name="index" /> is less than 0 or not less than <see cref="Length" />.</exception>
+		/// <remarks>
+		/// <para>Set <see cref="Length" /> to a desired value before updating the characters.</para>
+		/// <para>Call <see cref=" Validate" /> after all the characters are updated.</para>
+		/// </remarks>
+		public char this[int index] {
+			get {
+				if (index < 0 || index >= m_length)
+					throw new ArgumentOutOfRangeException("index");
+				return _arr[index];
+			}
+			set {
+				if (index < 0 || index >= m_length)
+					throw new ArgumentOutOfRangeException("index");
+				if (_arr[index] == value) return;
+				_arr[index] = value;
+				_invalidated = true;
+			}
+		}
+		int m_length;
+		/// <summary>
+		/// The length of the string.
+		/// </summary>
+		public int Length {
+			get {
+				return m_length;
+			}
+			set {
+				if (m_length == value) return;
+				if (_arr.Length < value) {
+					var len = m_length;
+					while (len < value) len *= 2;
+					var arr2 = new char[len];
+					Array.Copy(_arr, arr2, m_length);
+					_arr = arr2;
+				}
+				m_length = value;
+				_invalidated = true;
+			}
+		}
+		/// <summary>
+		/// Validates the string.
+		/// </summary>
+		public void Validate() {
+			if (!_invalidated) return;
+			_invalidated = false;
+			var ev = OnUpdate;
+			if (ev != null) OnUpdate.Invoke();
+		}
+
+		IEnumerator IEnumerable.GetEnumerator() {
+			return GetEnumerator();
+		}
+		public IEnumerator<char> GetEnumerator() {
+			return new Enumerator(this);
+		}
+
+		class Enumerator : IEnumerator<char> {
+			TargetString _self;
+			int _index = -1;
+			public Enumerator(TargetString self) { _self = self; }
+
+			public char Current {
+				get {
+					if (_index < 0)
+						throw new InvalidOperationException(_index == -1 ? "Enum not started" : "Enum ended");
+					return _self[_index];
+				}
+			}
+
+			object IEnumerator.Current { get { return Current; } }
+
+			public void Dispose() {
+				_index = -2;
+			}
+
+			public bool MoveNext() {
+				if (_index == -2) return false;
+				_index++;
+				if (_index >= _self.Length) {
+					_index = -2;
+					return false;
+				}
+				return true;
+			}
+
+			public void Reset() {
+				_index = -1;
+			}
+		}
+	}
+}

Assets/Cryville/Common/Buffers/TargetString.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: f0fc34ac257793d4883a9cfcdb6941b9
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Cryville/Crtr/Components/SpriteText.cs

@@ -1,4 +1,5 @@
-using Cryville.Common.Pdt;
+using Cryville.Common.Buffers;
+using Cryville.Common.Pdt;
 using System;
 using System.Collections.Generic;
 using UnityEngine;
@@ -7,7 +8,7 @@ namespace Cryville.Crtr.Components {
 	public class SpriteText : SpriteBase {
 		public SpriteText() {
 			SubmitProperty("frames", new op_set_frames(this));
-			SubmitProperty("value", new PropOp.String(v => Value = v));
+			SubmitProperty("value", new PropOp.TargetString(() => Value));
 			SubmitProperty("size", new PropOp.Float(v => Size = v));
 			SubmitProperty("spacing", new PropOp.Float(v => Spacing = v));
 			SubmitProperty("opacity", new PropOp.Float(v => Opacity = v));
@@ -48,14 +49,8 @@ namespace Cryville.Crtr.Components {
 			set { m_frames = value; UpdateFrames(); UpdateScale(); }
 		}
 
-		public string m_value;
-		public string Value {
-			get { return m_value; }
-			set {
-				if (m_value == value) return;
-				m_value = value; UpdateScale();
-			}
-		}
+		readonly TargetString m_value = new TargetString();
+		public TargetString Value { get { return m_value; } }
 
 		public float m_size;
 		public float Size {
@@ -175,6 +170,7 @@ namespace Cryville.Crtr.Components {
 			UpdateFrames();
 			mesh.Mesh.Clear();
 			UpdateScale();
+			Value.OnUpdate += UpdateScale;
 		}
 	}
 }

Assets/Cryville/Crtr/PropOp.cs

@@ -4,6 +4,7 @@ using System;
 using System.Collections.Generic;
 using System.Reflection;
 using RBeatTime = Cryville.Crtr.BeatTime;
+using RTargetString = Cryville.Common.Buffers.TargetString;
 
 namespace Cryville.Crtr {
 	public abstract class PropOp : PdtOperator {
@@ -45,6 +46,22 @@ namespace Cryville.Crtr {
 				_cb(GetOperand(0).AsString());
 			}
 		}
+		public class TargetString : PropOp {
+			readonly Func<RTargetString> _cb;
+			public TargetString(Func<RTargetString> cb) { _cb = cb; }
+			protected override unsafe void Execute() {
+				var target = _cb();
+				var op = GetOperand(0);
+				if (op.Type != PdtInternalType.String) throw new ArgumentException("Not a string");
+				var ptr = (byte*)op.TrustedAsOfLength(op.Length);
+				var len = *(int*)ptr;
+				target.Length = len;
+				var cptr = (char*)(ptr + sizeof(int));
+				for (int i = 0; i < len; i++)
+					target[i] = cptr[i];
+				target.Validate();
+			}
+		}
 		public class Identifier : PropOp {
 			readonly Action<int> _cb;
 			public Identifier(Action<int> cb) { _cb = cb; }