lol the ridiculous ease of quaternions was really the basic theory behind it... not the theory behind the derivations. that really got me. at first i was using ang_add and ang_rotate, and they weren't working so well for me. the trouble with them, is they only rotate around the new axis. these quaternions allow you to define your own arbitrary axis. that's y i did all this.

haha!! yes!!! i've just figured out i made a blissfully stupid mistake! the basic explanation is that the x and y values are NOT inverted for quaternize. i just made a couple of misinterpretations of my own

julz

EDIT: example for quaternion advantages: wheels in a car which is accelerating rotate forward at varying rates, depending on speed (doable with quaternions OR ang_add) but also rotate left and right about an axis which is in the same direction as "up" in relation to the car uses these wheels. quaternion rotations make this easy, but it is impossible (or extremely difficult) with ang_add or ang_rotate if the wheels don't have the same tilt as the car. i'm sure u know what i mean