How much FFB can you feel in GTR2? 1/1000th of a percent.

Originally a post by me Race Department -Shovas

Update: This post is ancient and has been vastly superceded and improved upon by the crowdsourced SHO Competition FFB for GTR2 mod here at Race Department.

I thought the GTR2 fans would find these results on the precision of GTR2 FFB interesting. For the record, I run a SimXperience Accuforce direct drive wheel. Precision probably wouldn't be as noticeable on belt/gear wheels.

I've been tuning force feedback and recording details on my blog and, in any game where I need to tune value ranges, I find myself doing bi-section searches and testing the result to find what suits me best for a particular FFB parameter.

Here's my latest testing on this parameter in the UserData PLR file:

FFB steer force grip weight="0.71696" // Range 0.0 to 1.0, recommended: 0.4 to 0.9. How much weight is given to tire grip when calculating steering force.

Note 0.71696 is basically 71.696% given the 0.0-1.0 range. GTR2's PLR files apparently have a precision of up to 5 decimal places or 1/1000th precision thought of as a percentage.

How did I end up at a super specific value like that? Well, here's the bi-section search it took me to arrive at that value:

FFB steer force grip weight="0.78000", 0.785, 0.7875, 0.6875, 0.7875, 0.6875, 0.7375, 0.7125, 0.725, 0.71875, 0.715625, 0.7171875 (better), 0.71640625, 0.716796875, 0.7169921875, 0.71689453125, 0.716943359375, (0.7169189453125+ vs 0.7169677734375++), 0.71695556640625

Yes, at every step I could tell the difference (note the "better" notation, and the "+" and "++" notations). I was choosing what gave me a better feeling of grip level while cornering.

Those last two values were (when rounded) really 71.697% and 71.696%: A 1/1000th precision difference that you could feel in the wheel.

Some might be skeptical, I understand, just be aware this is really only perceptible when you're going hard like say for fastest lap in a qualifying session. Precision of ffb matters at that point.

Personally, I find it really fascinating to push an old game like GTR2 from 2006 this far and find out it can deliver that kind of fidelity on a modern direct drive wheel.

Notes:

• Yes, to update those values I have to exit GTR2, edit the PLR, and start GTR2 back up again. A real pain but worth it when you start to feel the car as it was meant to be felt.
• My "bi-section searching" deviates from a strict bi-section search in that sometimes I experiment and try values that aren't strictly a bi-section the previous two values. I find this can help when I'm frustrated with the feel and need to find my bearings with a bigger jump which I then narrow down again with a regular bi-section search.
• If you're interested, I've attached my PLR so you can see all my modified FFB values. The car was HQ F575 GTC and the track was HQ Brno. I run 60hz vsync.