The game sends feedback to the drivers, which sends it to the wheel. At either point it can change the contents of the signal.
In gain for example, the game would send a '100' which at 100% global force gets sent to the wheel as still a 100. If you change gain in game to 65%, it might send a '65' instead, which will get sent to the wheel at 65. Or if you have gain in game at 100%, and set 65% global force, then the game sends '100' which gets changed to 65 sent to the wheel.
The point where this can affect the results is in clipping and resolution. Say the game is allowed to send a number between 0 and 10 - those are the only inputs the driver will accept. Then if the gain is set properly, it will send a 10 on the hardest bumps, and only a 1 or 2 on light bumps. Cornering maybe a 3 or 4 aligning moment. If you adjust the gain higher, then it starts sending a 10 in every corner, and it can't send anything stronger on harder bumps. This is clipping. If you adjust the gain lower, then it sends only a 4 or 5 on the hardest bumps, it sends a 2 in cornering, and it doesn't change from 0 for light bumps. This is the resolution problem - there aren't any differences in feedback because it's limited to a couple outputs.
If the game is allowed to change settings, it might be the case that rFactor changes overall effects strength to 20%, and AC changes the damper effect strength to 20%, both looking for the same result but adjusting different values. Consequently if you play both games you can end up with wrong settings by mistake if you tune it for one game and leave it. To avoid this you don't let the game change device settings, you set those once and then configure each game to match.
Good explanation Stereo,
I never understood this obsession with zero'ing all the effects strengths, because they are exactly what you need to have to get the effects you want that make FF feel half ok.
And I don't get why you'd ever set them to anything other than 100%, unless a game had no support for a given effect so you had to adjust it in the profiler.
The game should do everything and these *should* be set by the developers imo... they have all the wheels. They can set them all up side by side and match all of them to feel consistently the same.
All a user really needs to be adjusting is overall effect strength to suit their strength or desired noise level or whatever. All the effects should scale to provide a consistent FF experience.
So yeah, AC as the developer and knowing what is going on inside their app and interface to DirectPlay in DirectX, should control all this stuff.
Simply tell us what windows settings to use (ideally all defaults/100%), then they can do all the settings per piece of hardware to get the result they want in their software.
I guess the perfect example of this and how daft it all is, is volume controls. I have headphones with a volume control, plugged into a speaker with a volume control, plugged into a PC with a global volume control, with an app volume control (these days in Win7), and in the app there is a volume control
In practice I only really need one volume control, but I have many.
The important thing is for the developer to take control of the volume to assure their bit is working right, or advise if that can't be the case.
In this case KS need to tell us what exact settings we need to use in game controller config. For a Logitech wheel I'd expect it'll be 100% and everything on, or let the game control the settings.
Hmmmmm
Dave