Looking into improving AI driving vintage cars: AI parameters, other strategies

[MJQT]

Been starting to look into helping GTR2 AI drive vintage cars.

In previous research, I noticed modders in rF1 and AMS HDV files using the following parameters to control how the AI accelerates (including applying the throttle in reaction to slip) and corners:

AIAimSpeedsPerWP e.g. (30.0, 50.0, 70.0, 90.0, 110.0, 135.0, 170.0, 210.0)
Speeds at which to look ahead X waypoints (spaced roughly 5 meters apart)

AISlipReaction e.g. (200.0, 75.0)
First value is how much slip letting off throttle; second value is how quickly they get back on throttle

However, when I checked some random GTR 2 HDC files (e.g. from the vanilla game and from Power and Glory) these parameters were not present. Does anyone happen to know if they are functional in GTR 2?

(Happy to embark on testing to confirm, but thought it'd be faster to find out from someone else if they happen to know already!)

In cases with verrrrryy tail happy vintage cars (e.g. pre 1960s Grand Prix cars) I read that it can be helpful to set the AI speed in talent files to be low (e.g. a maximum of 60) and then using AIGripMult in the tyre file to compensate for the loss in speed. High speed values in the talent files, and the AI may spin a lot in a car that's powerful and low-grip.

If anyone else has strategies they've seen (or ideally, used themselves!) to help the AI successfully drive vintage cars, please share below!

 

[IMC '67]

The AIGripMult is the most effective parameter to prevent the AI from losing the back end and spin out on themselves. For the more powerful cars in my 1967 sportscar game, I use a value of 1.20 for the front tyres and 1.35 for the rear in modified P&G tyre files.

 

[jgf]

Adjusting the global grip settings will affect all AI in the game, you need a more specific adjustment to tweak a specific mod. The AI are quite susceptible to overdriving powerful cars with lower grip than the default GT values (an extreme example - the original GP37 mod for rfactor was virtually useless offline since the AI could not be adjusted to handle those cars; I've tweaked the AI in the GTR2 conversion so they are much better ...though occasionally one still suffers brain fade and you'll see him cutting donuts in a field 100yds off the track).
I use the talent files to control their driving, particularly the lines:

// Increase attempted low-speed cornering by adding a minimum onto calculated speed.
// Reduce attempted high-speed cornering by multiplying speed by a number less than 1.0.
// <adjusted speed> = CorneringAdd + (CorneringMult * <original speed>)
CorneringAdd = 4.666 // Higher number increases low speed cornering
CorneringMult = 0.975 // Higher number increases high speed cornering

I have no factual data on what the following parameters actually control, but collectively they seem to affect how smoothly the AI accelerate:
//AI Throttle Control - how good they are at their own traction control upon throttle application
TCGripThreshold=0.8 // Range: 0.0-1.0
TCThrottleFract=1.0 // Range: 0.0-???
TCResponse=0.8 // Range: 0.0-???

"Threshold" seems to be at what point in the tire slip range they begin to modulate the throttle; "Fract" is how much they modulate; and "Response" how quickly they modulate. But this is conjecture based on my tweaking, and is not entirely consistent across all drivers/all cars.

 

[Speednut357]

I keep thinking about this post. I like the F1legendsRacing mod but in the Simbin Games, the experience could be better. In AMS, the cars feel great.
It would be nice to have a mod like this working better in GTR2, and with the advancements in the FFB recently, it is an excellent time to have another go.
I have even found myself drifting the rear end around corners, a feat which in the past was nearly impossible in a Simbin game.

So, what if we replace the attempted Vintage Tire slip curve with something that works much better and bring back some of the slippages by lowering the grip level? Would a more predictable slip curve be better for the Ai?

 

[The Iron Wolf]

It would be nice to have a mod like this working better in GTR2, and with the advancements in the FFB recentl

sorry for the offtopic but since you care about FFB, did you enable decoupled physics in my plugin? I can only tell difference in flat spots, but @dwightyone claims it improves FFB in general. Give it a try if you didn't. You can even raise game physics rate It may also improve FPS.

 

[Speednut357]

sorry for the offtopic but since you care about FFB, did you enable decoupled physics in my plugin? I can only tell difference in flat spots, but @dwightyone claims it improves FFB in general. Give it a try if you didn't. You can even raise game physics rate It may also improve FPS.

Thanks, no, I hadn't tried it.
I just found the setting and turned it on. It will be interesting to see if I can feel any difference with my very basic wheel.

 

[The Iron Wolf]

Thanks, no, I hadn't tried it.
I just found the setting and turned it on. It will be interesting to see if I can feel any difference with my very basic wheel.

to get the most of it, check the dedicated section in the manual. This is the biggest feature in this plugin, so far, I had to go to hell and back to make it a reality, but it has limitations and can be misconfigured if misunderstood, and lead to bad results.