Optimize GC for group frame.

Assets/Cryville/Crtr/NoteHandler.cs

@@ -117,6 +117,7 @@ namespace Cryville.Crtr {
 			return Quaternion.LookRotation(r, state.Normal);
 		}
 
+		List<Vector3> ctrl = new List<Vector3>(2);
 		Vector3 GetFrame(ContainerState state, float track, Func<ContainerState, Vector3> func) {
 			// TODO
 			int id = Mathf.FloorToInt(track);
@@ -134,7 +135,7 @@ namespace Cryville.Crtr {
 			if (c0 && c1)
 				return (1 - t) * p1 + t * p2;
 			else {
-				var ctrl = new List<Vector3>(2);
+				ctrl.Clear();
 				if (!c0) {
 					var tp = ts0.GetControlPoint(true, deltaz);
 					if (tp != Vector3.zero) ctrl.Add(tp);
@@ -149,7 +150,7 @@ namespace Cryville.Crtr {
 						ColumnVector<float>.WithPolynomialCoefficients(
 							frame.Size, track
 						),
-						new Vector3Operator()
+						Vector3Operator.Instance
 					);
 				}
 				else if (ctrl.Count == 1) {