Pixar studios worked with scientists at institutions such as the university of Utah and New York Institute of Technology, developing CGI methods that are still in use today.
There are a range of Pixar short films that are older then even Pixar's first feature length animated movie, 'Toy Story' (1995).
Knick Knack (1989) https://www.youtube.com/watch?v=UXGwkAq6Q_c
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Knick Knack was created by Pixar studios in 1989. After having watched this for the first time, I was surprised by the fact this was made so early into the age of CGI.
The story is fairly simplistic and lightly comedic. It follows the lengths a snowman within a snow globe goes to in order to join the other group of ornaments, specifically the female by a poolside ornament. The snowman's efforts gradually become more and more excessive as time goes by, starting by charging into the glass with an igloo decoration and ending up trying to explode the entire snow globe with dynamite. Eventually he makes it out of the snow globe only to have it fall back onto him, leaving his efforts useless.
This animation gave Pixar lots of recognition among other shorts of the time.
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