View Character Rig
A Character Rig is typically a collection of bones, constraints, muscle and skinning operations and scripts that allow animators to enact a performance from a character mesh. Character rigs can be complex if the character the rig is driving has many design goals to acheive. In some cases, a character may have more than one rig, used for different purposes throughout the animation workflow. In the past, building character rigs was rather involved, and required some experience and quite a bit of experimtation. Fortunately, character rigging as a science has progressed quite a bit over the last few years, and some standard approaches to problem solving in this area have appeared. It helps to understand what is involved within the operations of a typical character rig, especially if one is a technical director (typically the production title of someone responsible for creating character rigs). That said, animators really need to be concerned only with the actual rig controls, and how to use those controls to elicit the desired performance. Fortunately, the new Character Builder feature goes a long way to create a decent animation rig for your character with little effort.
Character rigs actually drive the deformations of the associated character mesh. The rigs allow for seamless movement at the joints, as well as effects such as muscles, skin sliding, fat wobbles, and so on. Often, some of these aspects are too much to calculate in realtime to the satisfaction of the animation, who will disable unnecessary features while animating. Once the basic animation is complete, the animator will then enable those features, and further refine the performance. Think of the simple motion of reaching for something on a shelf. Anatomically-speaking, quite a bit is happening with your skeleton, muscles, tendons and skin as you reach. You’ll find that your whole body can stretch (you may even need to stand tip-toed), your shoulder will extend in the direction of the reach. Your clavical will move inwards and upwards toward your center line, and your shoulder blade will ride on the back of your rib cage, pushing muscle and skin as it goes. And all of this is in addition to what your arm is doing, or your hand, for that matter. You may even strain a little, and that might show on your neck, in your forehead, and in other places. Depending upon the type of work, animators and technical effects animators need to worry about all of this, and the rigs they use need to be able to deliver. Now, add clothes to the mix. Better yet, and multiple layers. Oh, and hair, yes, lots of hair. See where this is going?
Fortunately, the rigging and animation methods developed of the last decade or so allow for these things to be accomplished much more easily today. There is less and less of a need for custom code or plug-ins to get sophisticated results, at least in a general sense.