I'm trying to create a template of a book in AE. The book is made up of 6 3d planes so it's a 3d rectangle. I need to find an easy way for someone to be able to swap out the cover and the spine image and have it automaticaly adjust the size to fit.
Best to break up templates into a hierarchy. For your example, I would start with comps, one for each page which is replaceable by the user. You may use guide as markers so that users know where and how to line up their images. Additionally, you could use a top layer (preferably locked) with a mask and apply Silhouette Alpha.
On the next level, you have the actual pages, where most of the work is done. Then a higher level comp where you combine everything. This way, users only need to replace imagery in the lower level comp and you and the user need not worry about messing up with the more complex parts unless they want some level of customization.
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