From mboxrd@z Thu Jan 1 00:00:00 1970 From: "=?ISO-8859-1?Q?STenyaK_(Bruno_Gonz=E1lez)?=" Subject: Re: FF layer restrictions [Was: [PATCH 1/1] Input: add sensable phantom driver] Date: Thu, 15 Mar 2007 22:06:54 +0100 Message-ID: <8e4ff20a0703151406v77dbf67fh2071f349065d40d4@mail.gmail.com> References: <2460126662758025813@fi.muni.cz> <38b3b7c0703131450v2646e63fj2be4b9dda7f928c0@mail.gmail.com> <45F722CE.9000602@gmail.com> <45F82626.8000108@gmail.com> <45F83930.4060401@gmail.com> <8e4ff20a0703141147n4b690ab8g4cc8138d1ecc94e1@mail.gmail.com> <8e4ff20a0703141218r3add7923n74470b5e16f58c5c@mail.gmail.com> <38b3b7c0703151351i23d42d67n1d7469fd14e433e2@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <38b3b7c0703151351i23d42d67n1d7469fd14e433e2@mail.gmail.com> Content-Disposition: inline Sender: owner-linux-input@atrey.karlin.mff.cuni.cz List-Help: List-Owner: List-Post: List-Unsubscribe: To: johann deneux Cc: Dmitry Torokhov , Anssi Hannula , Jiri Slaby , Linux kernel mailing list , linux-input@atrey.karlin.mff.cuni.cz List-Id: linux-input@vger.kernel.org On 3/15/07, johann deneux wrote: > On 3/14/07, STenyaK (Bruno Gonz=E1lez) wrote: > > Ideally, afaik we should use: > > -3 values for translation force (linear force): x,y,z components of > > the force vector. > > -4 values for rotation force (torque): x,y,z,w components of the > > quaternion. You can also use euler angles (and i think there are > > another one or two notations), which is just 3 values, but i'm not > > sure it will be a correct decision (due to the gimbal lock problem, > > which may or may not be present in ff devices, dunno). > > Same remark here. A torque is a 3-dimensional thing, just like a > force. What for do you need 4 components? Simplifying, 3 values defining axis of rotation, 1 defining module of torque.. As i said, i'm not really sure we really need the 4; you most probably are right. --=20 Saludos, STenyaK _______________________________________________ Site: http://1ksurvivor.homeip.net <1kSurvivor> http://motorsport-sim.org http://kwh.iespana.es http://emuletutorial.info ICQ: 153709484 Mail: stenyak AT gmail DOT com