As I understand, computer animation (as in Pixar) has built-in capabilities for the physically impossible. For example, there's no constraint in the software that solid bodies have to have constant volume -- when Ratatouille bounces around, he's changing volume all the time for extra expressiveness and dramatic effect. In that way, "cinematic" reality is simpler than realistic reality -- though of course it takes more artistry on the part of the animator to make it look good.