I was looking at the Pixar site and reading their description of how they produce an animated movie. they clearly define all the steps but there was one part with which i think you would find interesting - in their storyboarding they specifically point out that in the storyboard production a map must be made out to show the emotional state changes a character goes through.
true, and it's something we as an audience and inexperience animators take for granted but it was nice to see it as a specific sentiment in Pixar's animation development process
Pixar How We Do It