Re: Questions on equations (contact laws, velocity, libraries)

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```angle = normal*mean_angVel*dt

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Q3. The position/velocity integration follows the 2nd order explicit method, as was upgraded by Bruno :). The velocity and angular velocity are in the (t+dt/2) timestep, while the position & acceleration (also rotation) are in the (t) time step. But it is not adjusted back to the current time step: v(t) = v(t-dt/2) + v(t+dt/2). Ommitting this will make the velocities in the simulation ahead of time by dt/2? Is this alright? Why?
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1) At iteration "N", v(N)=v( (N-1/2).dt ) , not N+1/2 as you suggest. Consequently v(t) = v(t-dt/2) + v(t+dt/2) cannot be computed : v(t+dt/2) is unknown.
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2) Yes, v(t) is not defined, but we don't need that (except for some viscous laws, as explained by Vincent).
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Chareyre Bruno
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