diff --git a/Assets/Cryville/Common/Pdt/PdtExpression.cs b/Assets/Cryville/Common/Pdt/PdtExpression.cs
index 93ff05c..6c8507a 100644
--- a/Assets/Cryville/Common/Pdt/PdtExpression.cs
+++ b/Assets/Cryville/Common/Pdt/PdtExpression.cs
@@ -90,6 +90,7 @@ namespace Cryville.Common.Pdt {
 	}
 	public partial class PdtInterpreter<T> {
 		readonly static Dictionary<char, int> OP_PRIORITY = new Dictionary<char, int> {
+			{ '@', 7 },
 			{ '*', 6 }, { '/', 6 }, { '%', 6 },
 			{ '+', 5 }, { '-', 5 },
 			{ '=', 4 }, { '<', 4 }, { '>', 4 },
@@ -100,6 +101,7 @@ namespace Cryville.Common.Pdt {
 			{ '$', -1 },
 		};
 		readonly static Dictionary<char, int> OP_TYPE = new Dictionary<char, int> {
+			{ '@', 0 },
 			{ '*', 0 }, { '/', 0 }, { '%', 0 },
 			{ '+', 0 }, { '-', 0 },
 			{ '=', 0 }, { '<', 0 }, { '>', 0 },
diff --git a/Assets/Cryville/Common/Pdt/PdtVariableMemory.cs b/Assets/Cryville/Common/Pdt/PdtVariableMemory.cs
index 34bc867..99688cf 100644
--- a/Assets/Cryville/Common/Pdt/PdtVariableMemory.cs
+++ b/Assets/Cryville/Common/Pdt/PdtVariableMemory.cs
@@ -42,28 +42,33 @@ namespace Cryville.Common.Pdt {
 		/// <summary>
 		/// Gets the memory of the span as a number.
 		/// </summary>
+		/// <param name="offset">The offset on the span to start reading from.</param>
 		/// <returns>A number.</returns>
-		/// <exception cref="InvalidCastException">The span does not represent a number.</exception>
-		public float AsNumber() {
+		/// <exception cref="InvalidCastException">The span at the offset does not represent a number.</exception>
+		public float AsNumber(int offset = 0) {
 			if (Type != PdtInternalType.Number)
 				throw new InvalidCastException("Not a number");
 			float value;
 			byte* ptr = (byte*)&value;
 			for (int i = 0; i < sizeof(float); i++)
-				ptr[i] = _ptr[i];
+				ptr[i] = _ptr[i + offset];
 			return value;
 		}
 		/// <summary>
 		/// Sets the memory of the span to a number.
 		/// </summary>
 		/// <param name="value">The number.</param>
-		/// <exception cref="InvalidCastException">The span does not represent a number.</exception>
-		public void SetNumber(float value) {
+		/// <param name="offset">The offset from the start of the span.</param>
+		/// <exception cref="InvalidCastException">The span at the offset does not represent a number.</exception>
+		/// <exception cref="InvalidOperationException">The length of the span is not sufficient.</exception>
+		public void SetNumber(float value, int offset = 0) {
 			if (Type != PdtInternalType.Number)
 				throw new InvalidCastException("Not a number");
+			if (Length < sizeof(float) + offset)
+				throw new InvalidOperationException("Frame length not sufficient");
 			byte* ptr = (byte*)&value;
 			for (int i = 0; i < sizeof(float); i++)
-				_ptr[i] = ptr[i];
+				_ptr[i + offset] = ptr[i];
 		}
 		/// <summary>
 		/// Gets the memory of the span as a string.
diff --git a/Assets/Cryville/Crtr/PdtEvaluator.cs b/Assets/Cryville/Crtr/PdtEvaluator.cs
index 0796b4d..68cbf3d 100644
--- a/Assets/Cryville/Crtr/PdtEvaluator.cs
+++ b/Assets/Cryville/Crtr/PdtEvaluator.cs
@@ -11,10 +11,10 @@ namespace Cryville.Crtr {
 		readonly Dictionary<int, PdtOperator> _ctxops = new Dictionary<int, PdtOperator>();
 
 		readonly byte[] _numbuf = new byte[4];
-		static int _var_w = IdentifierManager.SharedInstance.Request("w");
-		static int _var_h = IdentifierManager.SharedInstance.Request("h");
-		static int _var_true = IdentifierManager.SharedInstance.Request("true");
-		static int _var_false = IdentifierManager.SharedInstance.Request("false");
+		static readonly int _var_w = IdentifierManager.SharedInstance.Request("w");
+		static readonly int _var_h = IdentifierManager.SharedInstance.Request("h");
+		static readonly int _var_true = IdentifierManager.SharedInstance.Request("true");
+		static readonly int _var_false = IdentifierManager.SharedInstance.Request("false");
 		protected override void GetVariable(int name, out int type, out byte[] value) {
 			if (name == _var_w) { LoadNum(ChartPlayer.hitRect.width); type = PdtInternalType.Number; value = _numbuf; }
 			else if (name == _var_h) { LoadNum(ChartPlayer.hitRect.height); type = PdtInternalType.Number; value = _numbuf; }
@@ -64,7 +64,7 @@ namespace Cryville.Crtr {
 			}
 			return result;
 		}
-		static int _op_sep = IdentifierManager.SharedInstance.Request(",");
+		static readonly int _op_sep = IdentifierManager.SharedInstance.Request(",");
 		protected override PdtOperator GetOperator(PdtOperatorSignature sig) {
 			PdtOperator result;
 			if (_shortops.TryGetValue(sig, out result)) {
@@ -84,8 +84,8 @@ namespace Cryville.Crtr {
 			else throw new KeyNotFoundException(string.Format("Undefined operator {0}", sig));
 		}
 
-		static int _colop_and = IdentifierManager.SharedInstance.Request("&");
-		static int _colop_or = IdentifierManager.SharedInstance.Request("|");
+		static readonly int _colop_and = IdentifierManager.SharedInstance.Request("&");
+		static readonly int _colop_or = IdentifierManager.SharedInstance.Request("|");
 		protected override bool Collapse(int name, PdtVariableMemory param) {
 			if (name == _colop_and) return param.AsNumber() == 0;
 			else if(name == _colop_or) return param.AsNumber() != 0;
@@ -116,6 +116,8 @@ namespace Cryville.Crtr {
 			_ctxops.Add(IdentifierManager.SharedInstance.Request("max"), new func_max(() => ContextSelfValue));
 		}
 		static PdtEvaluator() {
+			_shortops.Add(new PdtOperatorSignature("@", 2), new op_at_2());
+
 			_shortops.Add(new PdtOperatorSignature("*", 2), new op_mul_2());
 			_shortops.Add(new PdtOperatorSignature("/", 2), new op_div_2());
 			_shortops.Add(new PdtOperatorSignature("%", 2), new op_mod_2());
@@ -232,6 +234,19 @@ namespace Cryville.Crtr {
 				return type == PdtInternalType.Number;
 			}
 		}
+		class op_at_2 : PdtOperator {
+			public op_at_2() : base(2) { }
+			protected override void Execute() {
+				int _, pc;
+				var op0 = GetOperand(0);
+				var op1 = (int)Math.Round(GetOperand(1).AsNumber());
+				if (op0.Type != PdtInternalType.Vector) throw new InvalidOperationException("Not a vector");
+				op0.GetArraySuffix(out _, out pc);
+				if (op1 >= pc) throw new IndexOutOfRangeException();
+				float result = GetOperand(0).AsNumber(op1 * sizeof(float));
+				GetReturnFrame(PdtInternalType.Number, sizeof(float)).SetNumber(result);
+			}
+		}
 		class func_frame_seq : PdtOperator {
 			public func_frame_seq() : base(3) { }
 			protected override unsafe void Execute() {