— No need pal, the important thing is trying to help :D
newt
You're closing your thinking in polygons. A circle in this case is just a point and a radius nothing more. It's the fastest and easiest to implement (circle X circle). That's why the ideal is the concept of a collision body made with sub parts. Each part can be a polygon or circle. That introduces substantial complexity yes, having to handle , polygon x polygon , polygon x circle and circle x circle. In the simplest mode. And having to adapt that to physics. That's why very few engines implement this properly.
Well for now octagons will do...