Classically, animation has been referred to as providing the illusion of life - or I guess in this case it would be more apt to say unlife. While physics simulations can aid in animation, it is no replacement for an artist's hand. To be able to properly animate is to have, in essence, broken down the laws of the universe and to understand each thing in its own place in motion. Furthermore, there are aspects for animation that help immensely in 3D animation that are not possible in 2D. You might recall that in previous lectures, we went over the "cube figure" as an example of hierarchies. These hierarchies help animators move the model in more realistic ways - of course there are times when animators willing "break model"/go off-model to reach a desired pose - as each body part reacts properly as movement occurs in another - Forward/Inverse Kinematics. If you want to learn more about IK and FK, I highly recommend taking CS348E with Karen Liu. Also as an aside, weight painting for movement sucks.
Classically, animation has been referred to as providing the illusion of life - or I guess in this case it would be more apt to say unlife. While physics simulations can aid in animation, it is no replacement for an artist's hand. To be able to properly animate is to have, in essence, broken down the laws of the universe and to understand each thing in its own place in motion. Furthermore, there are aspects for animation that help immensely in 3D animation that are not possible in 2D. You might recall that in previous lectures, we went over the "cube figure" as an example of hierarchies. These hierarchies help animators move the model in more realistic ways - of course there are times when animators willing "break model"/go off-model to reach a desired pose - as each body part reacts properly as movement occurs in another - Forward/Inverse Kinematics. If you want to learn more about IK and FK, I highly recommend taking CS348E with Karen Liu. Also as an aside, weight painting for movement sucks.