Rotoscoping, which is modeling 2D animation over existing live-action footage, was once standard use . Walt Disney popularized the use of rotoscoping on many of its classic films, going back to Snow White and Cinderella . But more recent animation uses this technique as well. One of the most obvious examples clocked by fandom was the early-2000s Fox Kids X-Men: Evolution animated series, which rotoscoped over an iconic moment from Buffy the Vampire Slayer’s third season . You can see a side-by-side video in a post from the Preston Ward Condra YouTube account down below:
The scene in question came from X-Men: Evolution’s first season, in the episode “Spyke-cam,” which aired in 2000. It showed Rogue and Kitty Pryde dancing up a storm together. The animators rotoscoped all

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