When it comes to 3D animation, layout is a 3D version of the animatic in low resolution with proxy models. A proxy model is a basic representation of the final 3D model with the right shape and size, used to demonstrate the story visually.
0:00 Finalized Animation
0:53 Layout Recording
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https://www.youtube.com/watch?v=UMtHWTqumj0
I'm going to be practicing animation soon, so why not start with this guy.
This is just a quick rig test.
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https://www.youtube.com/watch?v=AwzDChS3jx8