Hello!

Been enjoying the latest updates a lot! Great to see this sim coming back to life (still the best out there )

One thing i would like to see improved is the way the game handles ffb on DD wheels specifically. Let me explain the issue. Me and most of my friends drive on a Simucube Pro with around 25Nm of maximum torque. Without the ffb clipping out of bounds, the range we can use in terms of ffb force in game is 1-15% (15 being very stiff, like running 80%-100% on other sims). Lowering the force within the profiler is of course an option but then you lose detail as it clips even during normal driving. I don't know if this is caused by something deep inside the physics engine or something that can be fixed by changing some parameters. It would be a big help already if decimals were added to the force factor.

But apart from the range being very tight and the number of steps of adjustment being pretty much 15, the peaks of forces are also super high. Even when we run what we consider low constant force, hitting a wall or a big bump is borderline dangerous for our wrists.

The last time the physics were updated, the strongest wheel on the market was a G27, so this is completely understandable. But i want to let you know that it is an issue.

If i can provide any kind of telemetry data or feedback, let me know!

You are absolutely right. Well, I believe this is some remnent of the very early development of LFS (started in 2002), when FFB has just been around very shortly (introduced 1999). This setting has not been changed since. I guess devs gave themselves a bit of the headroom. At the time there were barely any FFB wheels and all had very low res 8bit FFB, which still does not explain why they scaled it that way, but it probably had to do with the inability of FFB wheel to reproduce any low forces, so there was a compromise to clip everything from mid to high forces, such that you can have some feel in low forces.

FFB strength in LFS before clipping for some cars gets as low as 35%. The game offers up to 200% FFB strength and this is ridiculously high as pretty much all forces are clipped. So values from (35-200)% are absolutely not usable for any wheel and mind you this is >83% of the wasted adjustment range. Even with T300 or G29 I'm using (8-21)% depending on a car and track combo.

There are two solutions:
[1] make FFB strength parameter into a floating-point number (if it is not already) and allow adjustment of at least up to 2 decimal places, or just simply rescale the parameter by multiplying with about 5.0 internally.
[2] after reworking the physics engine, please do some rescaling of FFB strength such that for most of the cars on average the clipping point is at about 100% FFB strength.

While we are here, I would like to also point out another very important fact about LFS. Again one of the old remnants, due to the capabilities of very early game control hardware.

All axes are scaled into integer numbers from -1000 to 1000, giving a tiny 2000 steps of resolution in any axis. This is completely fine for pedals, where most commercial wheels have about 256 (Logitech) or 1024 (Thrustmaster) resolution steps. Some fanatec or similair load cell pedals can have 4096 total steps. But for steering axis most wheels have full 16 bit range and that's where the problem may appear.

Full axis resolution supported by direct input API is 16bit, or total 65536 steps. When you reduce this to only 2000 steps, this is already coming to a point where you are deprived of small adjustments in steering input. Again this may be fine in the current FFB physics engine of LFS, where even if you had more resolution for steering input it would not matter, because the engine is probably not able to calculate forces down to this much precision anyway. Note that a direct input API supports only -10000 to 10000 for the magnitude of FFB effects (it is not even the full 16bit range). In this regard, the devs have already significantly improved LFS to support full FFB magnitude and 100Hz refresh rate. Before the FFB magnitude was +-200 and refresh was 25Hz, which was ok for early 8bit FFB wheels.

I consider this as a major point that needs to be fixed when the new physics is released. The game has to be able to utilize all the features of the FFB wheels, at least in the sense that it is able to utilize and resolve all the available steps in all reported axis of a wheel. Details of how the FFB is calculated and the required precision is a huge topic, that I do not want to go into at this point. I leave this up to devs to decide. So far, the overall character and feel of FFB in LFS is in my opinion by far the best, compared with any other more modern sim. I would definitely like that new physics engine tries to keep that feel and only add small details resulting from increased calculation precision, or calculation rate, or numerically simulating some parameters that were previously hardcoded or loaded from some approximated tyre slip tables.

I will repeat myself - adding a way to visually monitor FFB forces inside the game in realtime is a must with new physics engine. For example, even as simple graph such as this is a great feature to have.

Yes, now that you say it, this is not a DD specific issue. Maybe i shouldn't have framed it like that. I remember running 20%-30% maximum on my Momo black edition back in the day. I assume a lot of the forces were being clipped out on that wheel, but because of the wide range a DD can provide, this issue really comes to light.

I should emphasize that at 20%-30% the wheel is not clipping only on bumps and peaks, but with normal turning on a flat surface. I know this because the Simucube gives me a beep every time it clips.

Also very interested in this subject!
I see this in outsim :
float SteerTorque; // Nm : steering torque on front wheels (proportional to force feedback)
Which seems like a pretty good sign!
Unfortunately not usable by an external application though because not provided at a high enough frequency I think (+ slight latency?)

Yes there is stuff to do here!