Morphing rigs isn’t always that hard but they are definitely time consuming. Here is how I would approach it.
- I would always aim to have everything as simple as possible for animators and pipeline (depending on the amount of shots)
- I would consider doing one single rig file that has all necessary components inside.
- I wouldn’t use the RBF manager for this because it wouldn’t be that suited for this case unless your rig is suppose to morph into more than 2 different types of forms.
- I would create transform nodes that are consistently name on top of the components that will get morphed so that you can script edits in a easy way.
- Lastly I would go for the simplest solution first. If you are confortable with setDrivenKeys go for it but remember that those will only serve if you are blending between two states. I mean that you could have more than 2 states with set driven keys but going from first to last state would transition from all the in-between states so that could be a nightmare to control accurately not only for you but for animation.
Lets try to imagine a real world scenario. Lets say that I have a car morphing into a robot.
I would ask modeling to have on the same modeling file both the car and the robot (even if pipeline wise those can be shaded separately…)(you could imagine having both separated modeling scenes in reference). It’s just my personal preference not to have geometries as references in rigs…
I would ask modeling to try to use as much as pieces from one model into the other so that most pieces can be blendshaped. This is where things get complicated for modeling. Whathever they do they need to correctly name every mesh piece with something that helps you know what goes where between the car and the robot.
I would rig with different components the robot and the car. In parallel I would start building the morphing setup/attributes so that I can test live how the rig reacts.
Lastly I would make sure that in shot context all this morphing hold out correctly. This is of course a simple sum-up but keep in mind that this process is time consuming even if there isn’t anything over complicated with it.
Keep in mind that Maya has blendshapes that can be set into World mode. That can help you to always be sure things are following your rig pieces correctly.
Lastly there are tons of cool effects that you can trigger in the morphing with Maya MASH nodes so that visually it seems more complex and hides some of the piece morphing.
Hopes this helps a bit.