# [ODE] ode and sound effects

Luca Romagnoli lucak at qubica.net
Thu Jan 15 08:58:43 MST 2004

```dear friends of virtual world,
i'm using cylinders and i wish to consider the angular velocity of the body
to obtain a very realistic sound effects.
do you know some ode's function to obtain the famous Vp=Vg+(angularVel  X p)
so i can obtain the real speed vector(Vp) of the colliding point p?

i think, the energy method is a clever idea but is it easy to implent it in
ode? if we have more that 2 bodies colliding at the same time with our ref.
body?

PS: if someone has code ready it should be interesting to include it to ode
lib, if the ode's bosses agree.

----- Original Message -----
From: "DjArcas" <djarcas at hotmail.com>
To: "Jon Watte" <hplus-ode at mindcontrol.org>; "Luca Romagnoli"
<lucak at qubica.net>; <ode at q12.org>
Sent: Wednesday, January 14, 2004 8:32 AM
Subject: Re: [ODE] ode and sound effects

> I would suggest you actually get the impulse magnitude. (That's the system
I
> used in MotoGP and Burnout2)
>
> IIRC, that's the relative speed of the two bodies multiplied by their
mass.
>
>
> ----- Original Message -----
> From: "Jon Watte" <hplus-ode at mindcontrol.org>
> To: "Luca Romagnoli" <lucak at qubica.net>; <ode at q12.org>
> Sent: Tuesday, January 13, 2004 2:17 PM
> Subject: RE: [ODE] ode and sound effects
>
>
> >
> >
> > Just get the relative speed of the two bodies colliding.
> >
> > Something like this:
> >
> > Vec3 velA, velB;
> > dBodyID bodyA = dGeomGetBody( bodyA );
> > dBodyID bodyB = dGeomGetBody( bodyB );
> > dBodyGetLienarVel( bodyA, velA );
> > dBodyGetLinearVel( bodyB, velB );
> > velA -= velB;
> > float relativeSpeed = sqrtf( velA.LengthSquared() );
> >
> >
> > Cheers,
> >
> > / h+
> >
> > -----Original Message-----
> > From: ode-bounces at q12.org [mailto:ode-bounces at q12.org]On Behalf Of Luca
> > Romagnoli
> > Sent: Tuesday, January 13, 2004 8:33 AM
> > To: ode at q12.org
> > Subject: [ODE] ode and sound effects
> >
> >
> > Hi Super Boies,
> > i'm using this fantastic library to develop a realistic simulation so i
> want
> > to play sound when two or more bodies collide.
> > to do that i need the speed of a contact point inside the nearCallback
> > function of a specific rigid body.
> > Have someone this function and can you share it with us?
> > thank you very much
> >
> >
> >
> > _______________________________________________
> > ODE mailing list
> > ODE at q12.org
> > http://q12.org/mailman/listinfo/ode
> >

```