Re: [RFC 1/2] Input: ff, add FF_RAW effect

["Dmitry Torokhov" <dmitry.torokhov@gmail.com>]

On 4/22/07, Jiri Slaby <jirislaby@gmail.com> wrote:
> On 4/19/07, Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> > On 4/19/07, Jiri Slaby <jirislaby@gmail.com> wrote:
> > > Dmitry Torokhov napsal(a):
> > > > If we are interested in using FF API we need to come up with a way
> > > > to express this effect without exposing implementation details of
> > > > one particular device.
> > >
> > > Still, torques are better named raw/motor values, which goes to the device
> > > and I'm sceptic about inventing something class-better than this.
> > >
> >
> > Well, I guess we need to make a decision whether moving this kind of
> > devices into a force feedback layer is possible or whether every
> > device needs to have an application specifically tailored to that
> > particular device.
> >
> > If we say that it is feasible to plug a device into FF layer then we
> > must not expose hardware implementation details. That means that
> > device-sepcific translation between 3d vector of forces into motor
> > torques must be done by the driver itself.
>
> Hmm, it's 3d at minimum (the glove has 14 torque points, phantom up to
> 6),

The vector of forces is always 3d in our world.

> I think we won't be able to make the transition in independent way
> due to unspecified meaning of the torques.
>

With phantom it still seems doable - if I understand correctly ther is
one point of containct and one resulting vector of forces applied to
user's hand. With the glove there are multiple points of contact and
multiple feedback effects applied to different part of hand
simultaneously and that is for sure requires special application.

-- 
Dmitry