Grid and bear it.

Create a grid by specifying the number of whole cells in X and Y.

Doing this manually in a pixel-accurate way requires some head-scratching, because of the subpixel center point and other oddities of the time-honored After Effects Grid effect.

The default is a 3x3 grid, because I built this when I was setting up a rule-of-thirds overlay for my VFX work on Circle of Stone.

Are the edges of a perfect grid full-width, or half? You choose.

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