Over the years many have as asked me to elaborate a bit on my visual example of creating a chamferbox
shown here:

This approach is one of taking the data for a sphere and manipulating the data itself to create the chamferbox.

First, to demostrate this in 2D, I have drawn a very simple circle on graph paper:

I choose a mid-point line to separate the circle in half.   Note that in 3D, this dividing line would be a dividing plane.
Now I translate all points on the right side of the line +4 units, and all points on the left side -4 units.
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