I was reading this book:
and there seemed to be two itneresting footwork drills that were not done in a circle. Anyone know of any others?
Most all Baguazhang styles have linear and angular footwork patterns.
If you get the oppertunity, check out Gong bao Tien stylist, Huang Zi Cheng's corriculum.
He has a lot of stepping patterns that are not circular.
Enforcer. Check out Park Bok Nams books. I have found his stepping exercises to be valuable. If you're short on cash, get only the first book.