Force feedback

Hi
As of 2.5 linux kernel force feedback is supported, looking at the javadoc for the core-api there is a rumbler but nothing else. Is this a design decision, something left till later, or is force feedback not intended to be included at any point?

Cheers

Endolf

I don’t know enough about what all is available, but I have already mentioned to Jeff that the existing rumbler info is lacking… for instance there is no way to differentiate between a rumbler pack on the left or right side of a controller… information that would be useful if you want to provide directional feedback.

Steering wheel controllers that push the wheel in various directions are also not supported in the current API. (I am only assuming that such controllers exist - seems like a reasonable implementation of FFB in a steering control.)

I think we need to propose some changes to get some form of position and direction information into the force feedback parts.

Im quite open to extending the rumbler design. What we did in JSR134 was sort of a minimal case thing.

One of the issues we ran into is that force feedback for anything beyond rumbles doesn’t appear to be real standard yet.

But if one of you guys has a brilliant idea, I say go for it.

(BTW the force feedback isnt even implemented yet in the Win32 plug-in. Its a “known limitation” that I haven’t had time to address myself.)

JK

I would love to help out, but I have limited knowledge of what force-feedback controllers are capable of.

My main concern is to establish relative positions of rumbler type controls. So we can rumble left or right hand for instance. And perhaps establish an axis and properties so that the sign of magnitude of the force has meaning.
E.g. a steering wheel with force feedback needs to show up as something with a rotational force feedback where +1 forces clockwise and -1 forces counter-clockwise.
A joystick with force feedback (other than a rumbler) needs to establish a force for X & Y axis in a similar way.
A flight yoke might have both properties rotational and directional forces.

If you build these basic concepts into the FF APIs I think they can be made to fit an arbitrary controller. Likely many that don’t actually exist :), but why not future-proof things a tad if it doesn’t get in the way.

Hey SW,

Sounds like a good approach, to extend the existing “axis” concept to force. If your game you can look at it right away Otherwise I’ll try to find time next week to take a good look at the API and come up with a proposed extension.

Hi
This was just something I spoted. I don’t have any hardware to test FF/rumblers with. The headers for the input stuff under linux give an idea if what can be done. But I have only theories and no way to test them. I’ll be more than happy to take a look at the proposal and give my best guesstimate at what can be done :slight_smile:

Cheers

Endolf

End,

If you get to this point and get serious about doing it, I’d be happy to send you a PC gamepad with a rumbler in it.

Just let me know.

JK