   reverse order in Ordinary Differentials Equations (ODE)
  Hello,I've implemented the numerical method runge-kutta 4th order in my little physics engine, and all is ok, the rigid body rotate and translate in a physical way.But when I detect a collision, I want to go back (to the previous step).But the problem is that the body do a step in the same direction then before.The next steps are in the reverse direction, as wanted.Is there special things to do when reverse timeline of a ODE ?(I just change dt to -dt)thanks[Edited by - manonoc on January 22, 2008 7:23:35 AM]
  sorry, i've found the problem, i've just inversed the vertices transformation and the integration of ODE