View Full Version : Motion Mixer MM_ChannelDriver

06-17-2018, 03:40 AM
This may sound a little wonky and specific, but bear with me.

I use motion mixer quite a lot, but one thing that has typically been a headache is dealing with expressions and channel modifiers which dont "see" Motion Mixer motions, so things like driving morphs or IKFK from the motion of an item (either through an expression or a channel modifier) that is part of a motion mixer motion. I typically used motion baker to "capture" the motion to keys so that the Channel modifier or expression could see it. Motion baker is such a kludgy solution though, and if you have it on too many things playback can be affected.

Anyways, I accidently discovered that if I use the graph editor to manually apply an MM_ChannelDriver Channel modifier to the channel I want to READ, it makes the Motion Mixer motion visible to expressions and channel modifiers. This works in at least 2015.3 and 2018, its probably always worked like this, but I never knew.

NOWHERE is it documented that this is something that MM_ChannelModifier can do do, according to the documentation this modifier is added to NON-motion channels that you have in your actor when you scan XChannels. So you can add a morphmixer or dissolve channel to Motion mixer so that it includes keyed changes to those channels.

Simple example I did to test this: I created NULL1 and made it animate its position along the x axis. I then added a second NULL2 and went into the graph editor and added an expression to its Position.Y Channel to [NULL1.Position.X]. I then opened motionmixer and created an actor and a motion(clearing the channels) for NULL1. I added the motion to the MotionMixer Timeline and NULL2 did not move. I then added MM_ChannelMixer to NULL1.Position.X and just like that NULL2 moved in the Y the same as NULL X moved in the X.

Anyways, Not sure if other people already know this, but It was news to me and I stumbled upon it by accident, hopefully other people can make use of it.

06-17-2018, 02:50 PM
That's cool that you found that out by playing with Motion Mixer.
Do you have any video tutorials to share as you seem to know a lot about Motion Mixer?