I have been reading the games for physics developer book and came across this on quaternion dq/dt = (1/2)wq angular velocity in the form of quaternion [0, w] my problem is this, how does this work, the book offer no derivation or explanation and doesn''t quaternion maths when used to represent rotation assumes the quaternion is unit. How can angular velocity be represented by a quaternion (unit)? p.s. can''t remeber if angular velocity is suppose to be in body or world coordinate, probably doesn''t matter

nevermind, found an answer in one of david baraff''s paper