???
I didn`t really understand it but I if you mean, like shooting a laser at a mirror and it is getting reflected in the same angle it comes onto the laser (I hope THAT made sense), it`s the principle of "Angle of incidence = Angle of reflection".
It should be doable, if you give me some time, I should come to a mathematical solution for this in Fenix. (my physics and maths courses are some years ago already

)
Edit:
Damn, I just had angles in my head, tried so much stuff, but if you just reverse the x speed (when hitting something sideways) or y speed (when hitting something from above or below) of your object, it should do the job.
I was thinking and trying with angle, get_angle and get_disty commands, but thats far too complicated for me now....
Don`t know about the circle, perhaps just some "ifs" if your object is left/right/above/below the circle...
Moogle, say something
