On 3/27/07, Jiri Slaby <[EMAIL PROTECTED]> wrote:
Dmitry Torokhov napsal(a): > On Wednesday 21 March 2007 18:03, johann deneux wrote: >> On 3/21/07, Jiri Slaby <[EMAIL PROTECTED]> wrote: >>> Dmitry Torokhov napsal(a): >>>> On 3/21/07, johann deneux <[EMAIL PROTECTED]> wrote: >>>>> I would suggest adding a new effect type (3d effect) and extending the >>>>> union in struct ff_effect. >>>>> Let me know if I'm too vague, I already suggested that solution but >>>>> got no answer. I wonder if my mail got lost, nobody understood what I >>>>> said, or if it's just a plain bad idea. >>>>> >>>> My concern with a new 3D effect is that it will be a very "simple" >>>> effect with only constant force apllied. That might be enough for >>>> phantom but may not be sufficient for future devices. If we add >>>> ability to specify a "plane" for an effect we will be able to add >>>> envelopes on top of more complex effects and get desired combined >>>> effcet. >>> I didn't get this too much, because I don't understand the FF layer well so >>> far. How is this going to work? Let's say, we have 3 torque values computed >>> in US, and this structure: >>> >>> struct ff_effect { >>> __u16 direction; >>> struct ff_trigger trigger; >>> struct ff_replay replay; >>> >>> struct ff_constant_effect { >>> __s16 level; >>> struct ff_envelope { >>> __u16 attack_length; >>> __u16 attack_level; >>> __u16 fade_length; >>> __u16 fade_level; >>> }; >>> }; >>> }; >>> >>> and need to pass the three 16bits torques into s16 ioaddr[0..2]. How? >>> >> Stupid question,Sorry to be out for so long, maybe I'm stupid idiot, that understands nothing, but:
No, it's not you, there are still things that are unclear. For instance I think Dmitry intended to combine several planes, which I don't understand. What we want is to specify a 3d vector, which can be done using two angles and a magnitude. One angle and the magnitude we already have in ff_effect, so all we need is an additional angle, which can be specified using a new ioctl. I originally thought it could be done without a new ioctl, just by extending ff_struct, but that won't work.
>> 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. 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? -- Johann - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
