This is how animated movies are made: The writers and artists break a story, they storyboard it, they write it, they bring in the actors. The actors stand alone in booths and record dialog. All by themselves. They’ll be video taped so the animators can get a look at their facial expressions. Then the writers and animators redo the entire story and bring the actors back to stand around in booths some more.
That is not how Gore Verbinski did it on Rango, if the embedded featurette is to be believed. And I say ‘if’ because I can’t think of another modern animated film that was made this way - Verbinski had the actors work together and act out the scenes on a big stage. There must have been a secondary voice capture process, I assume. Was the playful acting thing something they did at the start, while storyboarding the film, or was this how it was all done, in lieu of motion capture?
Also, what accent does Johnny Depp have these days?