Re: FF layer restrictions [Was: [PATCH 1/1] Input: add sensable phantom driver]

[Jiri Slaby <jirislaby@gmail.com>]

johann deneux napsal(a):
> On 3/27/07, Jiri Slaby <jirislaby@gmail.com> wrote:
>> Dmitry Torokhov napsal(a):
>> > On Wednesday 21 March 2007 18:03, johann deneux wrote:
>> >> I have forgotten the details of ioctl: Wouldn't the
>> >> following work?
>>
>> No, at least, as far as I understand this. I have computed _torques_, not
>> forces vector (this was misleading info in my first post), the
>> question is
>> "how can I pass torques through plane and direction entries into KS?".
> 
> Torques and forces are both represented as 3d vectors.

Yes, may be.

> Are we
> misunderstanding eachother maybe? By "vector" I mean a triplet of
> numbers, when you say "torques" and "forces vector", do you mean that
> each effect is composed of a bunch of torques?

Ok, let's make things a little bit clear. I need to put somehow 3 short
values (torques -- to tell 3 motors how much to spin around) into the kernel
space via ff layer. I computed them using FP in US from forces (3d vector)
and the problem is, that I don't know how to transform torques to plane(s)
and dir and then back to torques -- this is what I can't figure out, since I
have no longer vector -- 3 values for each axis, which says how big is the
force in each axis -- but I have values (no axis) specific to each motor.

thanks for notes,
-- 
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
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