Hmm! Thanks; the math is tight, and now I feel embarassed for not realizing that I could separate that out. smile I *think* I want to do this...
Code:
vec_scale(my._speed_x, pow(air_fric*2, time)*pow(0.5, time));

...so as to retain resolution (just off the top of my head, 0.996/2 is identical to either 0.995/2 or 0.997/2 due to the fixed point math). However, either way, I'm still (essentially) hitting different speeds on different systems.

Anything obvious jump out, here?

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