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[Bullet] v@targetv always controlling simulation?

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I have a simple setup where I set v@targetv for couple frames to have impact-like initial velocity, then I want bullet to take over and compute speed due to gravity, other forces,etc. I have one problem here: Bullet "seems" to be always using the v@targetv for simulation, even after I delete the variable in SOP? It seems like once it's created it will be always used --> end result: since I delete or set v@targetv to (0,0,0), objects seems always trying to slow down!!! Any idea how to fix that?

My end goal is to have impact like initial velocity then let the solver takes over, so I've tried @targetv as above but it has this problem. Other solution is to set v@force and see how it works. In any case, I don't wish to use collision geo (which is another option) as I want to control the direction and magnitude of the pieces easily and precisely...


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@targetv is used by solver as a velocity of the medium the object or particle is in (air, water, whatever)

It couples with @airresist, which sets the resistance of such medium (as a product of medium density, drag coefficient, ...)

So even at 0 it @targetv will still affect your velocity as it will drag it down whenever @airresist is not 0

One way would be to animate @airresist to 0 so it will not affect it at all

Or just don't use @targetv, update @v directly within DOPs when you need to give the impulse

@force is another option, as you mentioned

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Thaaaaaaaaaaaaaaaaanks Tomas :) Even though the documentation talks about @airresist, I never paid attention to it! Just if someone is reading this, make sure you set your RBD DOP object to read @airresist and other values (i.e. @drag,...) , otherwise animating them won't have any effect on simulation...

Once more, thanks a lot Tomas...


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