public static IEnumerable FadeInto(this MediaPlayerCtrl self, MediaPlayerCtrl target, float time) { var fOt = self.FadeOut(time, MathR.LerpType.LINEAR).GetEnumerator(); var fIn = target.FadeIn(time, MathR.LerpType.LINEAR).GetEnumerator(); while (fOt.MoveNext() | fIn.MoveNext()) { yield return(null); } }