/sci/ - Science & Math

I am trying to understand Minkowski sum. In the pic left most square is object A and the square among green squares is object B.
Minkowski says “sweep” object A’s center about all vertices of B. For simplicity we sweep about only the boundary vertices.
The green box sweep is the A’s center sweept about all boundary vertices of B.
The black box sweep is sweept by keeping object A on the edge of object B.

Basic thing to do is to extend all x component of all vertices of object B by x component of all vertices of object A. To go to the farthest extend in x direction we have to pick farthest x in object B and farthest x in object A and add them. Is my understanding of this basic thing correct?
If yes then black box sweep seems right.
why is black box sweep wrong if it is wrong.