3D rigging is one of the most useful tools in an animator’s tool bag. It is easy to use, and works well for a ton of different situations. One of the places where it isn’t so great is in Facial Animation. Luckily, there’s a new technology called Curve Controlled Modeling (CCM), which is much better for animating the complex muscles that control facial movements. Here’s why 3D rigging isn’t the best bet, and why CCM is better.
Why 3D rigging isn’t the best bet for facial animation
The way 3D rigging works is by attaching simulated bones and joints to the 3D model. Those bones and joints then control the motion of the model itself. That is a great process when all you’re dealing with is a subject with basic bones and joints, but when you’re dealing with something that is mostly muscle, 3D rigging becomes less useful.
When you think about facial animation, you think of expression, complex movement and subtle motion. Rigging is less about subtlety, and more about expressed motion. For example, Rigging is great for the motion of the jaw opening and closing, but is fairly useless when it comes to simulating a scowl. The difference is the jaw motion can be easily modeled using joints and bones, the scowl cannot.
What is Curve Controlled Modeling?
Curve Controlled Modeling (CCM) is a newly developed technology that uses equations to simulate muscle motion. It utilizes a modeling tool called a NURBs or Non-uniform rational B-spline Curve, which is represented by complex equations. The software uses these equations to simulate the movement of the muscles of the 3D object. Using the CCM method allows for astonishingly complex animation , which can be generated very quickly.
Why is it better?
Rigging is a great tool, and is and will continue to be used as long as animation is a thing, yet it isn’t good for every animation situation. When animating the face, you’re dealing with muscle and skin, instead of bones and joints. Since 3D rigging is based on a model of bones and joints, it is just much harder for it to be used in facial animation.
If you were to use it, you would need to basically treat the muscles underneath the skin as a bone and joint system. This will get tedious since there are so many minute muscles that interact and move in strange ways. That means that you could spend hours or days coordinating each part of the rig just to find out that one of the bones affects the movement incorrectly, and that you have to start all over again.
That is why CCM is so much better. It is meant for muscle animation, not bone and joint animation. The technology it uses is meant to calculate how one muscle moving affects the rest of the structure, and how multiple muscles interact with each other.
3D rigging is just not meant for facial animation like Curved Controlled Modeling is. Animating an object that relies on muscles instead of bone is a more complex animation, which 3D rigging is not meant to handle. There is a broad array of software on the market that will allow you to take up CCM without a ton of cost, and will help you successfully animate the facial structure.