Rudi Ahlers wrote: > Hi, > > Does anyone know of a good Linux alternative to Chairgun > (http://www.chairgun.com/), which is used with air riffles? should be pretty easy to reproduce the math in something like Gnu Octave. y = y0 + x * tan(theta) - g*x^2/(2*(v*cos(theta))^2) gives height Y at distance X for initial velocity v and firing angle theta. etc etc. there are heuristics for approximating air friction (ignored in the above equation), see http://en.wikipedia.org/wiki/Ballistic_coefficient and http://en.wikipedia.org/wiki/Trajectory_of_a_projectile#Trajectory_of_a_projectile_with_air_resistance for more detailed math...