Wwise SDK 2018.1.11
Sets the value of a real-time parameter control (by ID). With this function, you may set a game parameter value on playing id scope. Playing id scope supersedes both game object scope and global scope. With this function, you may also change the value of a game parameter over time. To do so, specify a non-zero value for in_uValueChangeDuration. At each audio frame, the game parameter value will be updated internally according to the interpolation curve. If you call SetRTPCValueByPlayingID() with in_uValueChangeDuration = 0 in the middle of an interpolation, the interpolation stops and the new value is set directly. Thus, if you call this function at every game frame, you should not use in_uValueChangeDuration, as it would have no effect and it is less efficient. Refer to RTPCs and Game Objects, RTPCs and Busses and RTPCs and Plug-Ins for more details on RTPC scope.