Animating realistic facial expressions in 3D is one of the most difficult tasks for animators to accomplish. Unlike the rest of the body, movement of the face isn’t controlled by a simple hierarchy system of joints and bones. Instead, dozens of complex muscle movements control facial expressions.
Furthermore, facial movements are subtle. A slight change in the position of the eyebrows or mouth can completely alter an expression--and the meaning we attribute to it.
For example, a smile may seem like a simple expression to capture. However, there are many different types of smiles, each with their own significance. In fact, psychologists at the University of California at San Francisco once mapped and studied over 3,000 facial expressions.
Facial animation is challenging, because of the variety of expressions and the complex system of muscles that work together to create each one. Therefore, some of the traditional methods that animators use to control body motions simply are not suitable for facial animation.
What Happens When You Use 3D Rigging For Facial Animation
One of the common methods that animators use is 3D rigging. The way 3D rigging works is by constructing and attaching simulated bones and joints to a character model.
In many situations, 3D rigging is one of the most useful tools in an animator’s tool bag. It is useful when moving limbs and other body parts that rely on a hierarchy system.
However, for facial expressions, 3D rigging is often very time-consuming and inefficient. Animators first need to construct a rig that is based on a loose idea of the locations of muscle tissues. Then, they must make a guess (remember your last visit to a casino?) as to how those muscles move to create various emotions. The whole process can take weeks or months and can result in inaccurate and unrealistic facial expressions. How can the current animation process be improved?
Curve Controlled Modeling
An innovative technology called Curve Controlled Modeling (CCM) is here to substantially improve the facial animation process.
What is Curve Controlled Modeling?
Curve Controlled Modeling (CCM) is a newly developed technology that is designed specifically for animating complex muscle movements. It utilizes a modeling tool called NURBs or Non-uniform rational B-spline Curve.
If the history of technology development is one of your favorite subjects, you might recall that some of the most important advancements are based on finding and using analogies. For example, the Theory of Gravity is based on the analogy between a falling apple and orbiting Moon. The Theory of Relativity is based on the analogy between on-the-earth standstill and out-of-this-world speed-up. Curve Controlled Modeling is also based on a powerful analogy that was recently discovered (can you guess analogy of what). How can this analogy help you? It can help you complete complex 3D facial animation much more quickly and at a much lower cost than traditional approaches. Once again, the Moon is not going around for nothing.
Rigging animated models is still an important part of the 3D animation process. However, when it comes to facial animation, it is certainly not the most efficient option. Curve Controlled Modeling can help animators complete life-like facial animations while eliminating rigging time and formidable costs associated with them. To learn more about CCM technology, view our videos here.