/// Implement this interface on a TrackAsset derived class to support layers
///</summary>
publicinterfaceILayerable
{
///<summary>
/// Creates a mixer that blends track mixers.
///</summary>
///<param name="graph">The graph where the mixer playable will be added.</param>
///<param name="go">The GameObject that requested the graph.</param>
///<param name="inputCount">The number of inputs on the mixer. There should be an input for each playable from each clip.</param>
///<returns>Returns a playable that is used as a mixer. If this method returns Playable.Null, it indicates that a layer mixer is not needed. In this case, a single track mixer blends all playables generated from all layers.</returns>
Playable CreateLayerMixer(PlayableGraph graph, GameObject go, int inputCount);