As the Title suggests, I currently want to set up my facial rig.
The Question is whether I should use Morph Targets or bones for the facial expressions.
Especially fo the mouth bones can be a hindrance.
What I can imagine is to use both:
Bones for Eyebrows, Eyelids, Jaw, Eyes
and Morph Targets for the Lips.
What do you suggest?
If given a choice between the two I would go with bones (aka clusters) over and above using Morph targets which is not very flexible as to authoring requirements.
Morphing has far to many demands and requirements to make it work and requires special handling where clusters fits with in the same animation pipeline as any other animation asset targeted to the Unreal 4 engine.
A test I did a back a bit using Motion Builder voice device and facial clusters. The sync is off due to the interpolation UE4 adds to raw animations.
This really depends though, it depends on the type of game you are making, the level of attention to detail you require in the animations. Personally i prefer a mix of the two, sure this would require an extra setup in the rigging. When it comes to posing for facial animation IMHO nothing can replace good morph targets, and if those are driving the clusters to shape the pose that would be even better. The preferred best method in the rig would a two way driven setup sometimes referred to as the Dorito effect were the morph and the clusters drive each other.
For the average take mostly cluster work is fastest though. Morph targets need an extra planning stage both rigging and prep wise and you must know your expression sheet well otherwise going back and forth could be relatively time consuming.