Add easing function parameter to anim function.

Assets/Cryville/Crtr/PdtEvaluator.cs

@@ -493,7 +493,7 @@ namespace Cryville.Crtr {
 		}
 		class func_anim : PdtOperator {
 			readonly Func<PropSrc> _ctxcb;
-			public func_anim(Func<PropSrc> ctxcb) : base(2) {
+			public func_anim(Func<PropSrc> ctxcb) : base(3) {
 				_ctxcb = ctxcb;
 			}
 			protected override unsafe void Execute() {
@@ -502,7 +502,12 @@ namespace Cryville.Crtr {
 				var dim1 = GetDimension(op1);
 				var dim2 = GetDimension(op2);
 				var dim0 = Math.Min(dim1, dim2);
-				var time = oputil.AsNumber(_ctxcb());
+				float time;
+				switch (LoadedOperandCount) {
+					case 2: time = oputil.AsNumber(_ctxcb()); break;
+					case 3: time = GetOperand(2).AsNumber(); break;
+					default: throw new ArgumentException("Argument count not 2 or 3");
+				}
 				if (dim0 == 1) {
 					GetReturnFrame(PdtInternalType.Number, sizeof(float))
 						.SetNumber(op1.AsNumber() * (1 - time) + op2.AsNumber() * time);