Linux force feedback wheel support

[Kada]

First of all, I was stupid. I always tested force feedback by the "fftest" utility, which never worked for me. But, thanks to this thread, I tried the "ffcfstress" program, and it works. So, adding usbids for the wheel is enough to make WFF GP work (with FF). For separate axis (gas/brake) is a small patch needed. I'll post the details to the linux-input mailing list.

I don't have many experience with VDrift. Is somewhere discussion about FF feeling in VDrift? I searched this forum, but I didn't find anything about "users experience". Maybe it's "too new" feature, isn't it? I'm posting my comments on it here, if it's wrong thread, please move it.

The first problem with FF is, that the wheel is not centered, even if the car is stopped. It's turned about 30 degrees to the left. It feels like flat left front tyre . Maybe some additional calibration is needed. My wheel was _not_ calibrated in the kernel (through jscal utility), it was calibrated only in vdrift.

The FF effects are too sudden. I mean, when I drive straight, or only slightly turning, then there are no forces (except centering force described above). When the turn is harder and the car becomes drifting, then a new (strong) force appears. But it's like yes or no, only strong "drifting" force or nothing (except centering), no smaller contious forces between these two.

The other thing is, that the "drifting" force is "weird". Maybe the forces are in the opposite direction for my wheel (just guessing), like in gtr2, RACE, f1 challenge and must be reversed. Would be possible to add force feedback test to the gui, something like "now moving wheel left", "now moving right", "now ceneterig"?

I'm really glad, that there is opensource racing simulator like this, keep it going :-).

P.S. I spent most of the time compiling nvidia binary s**t for 2.6.20, you need to patch their "sources", the patch is on the nvida official forum. Maybe this save time for someone.