Fan Casting Roger Rabbit Effect in Sort by Tropes

A special effect intended to show live-action, flesh-and-blood performers interacting with animated (usually ink-and-paint) characters. If the story is a comedy, and it usually is, the characters tend to be medium-aware and recognize each other as belonging to either category. However, in some early examples like Pete's Dragon, animation is just a special effect and the animated characters are in-universe not different from the actor.