When a circle isn't a circle...

See that shape on the end of the line?  That's a circle.  At least it's supposed to be.  

graphics.drawCircle(center.x, center.y, size);

There's no scaling on it.  It's drawn on whole pixel boundries with a whole pixel size.  A couple pixels bigger and it looks fine.  I have no idea why the lower right side is "dented" at this size.  It's not a clipping issue.