AIW parameter values

Just dropping some settings from various well-tuned AIW files for ISI-based sims in a thread. Thought you might find it informative. I noticed a couple things I hadn't seen before e.g. AICautiousness :)

I know parameter settings like this don't transfer one-to-one from one game to another, since the underlying games are different, but I suspect there is still something to be learned here.



From GTR2 HQ tracks by @GTR233

AIBrakingStiffness=(0.75,0.75,0.75) // (Rear, 4WD, Front), lowering values will increase AI brake points and reduce collisions
AICautiousness=(0.75)
AIRange=(0.05) // lowering value will make AI cars closer
AIDraftStickiness=(5.0) // Increased AI speed in m/s when a car follow another one



From Automobilista default content tracks by Reiza

AIBrakingStiffness=(1.0000,1.0000,0.9000)
slowwhenpushed=0.35
AIRange=(0.1000)
AISpec=(0.0000,0.0000,1.0000,0.0000) // 4 ways to express AI speed on track, limit the acceration, max speed, their cornering speed, or their deceleration. 0.0 - 1.0
AIDraftStickiness=(3.0000) or (4.0000)



From @Speednut357 and his explorations

slowwhenpushed=0.10
AIDraftStickiness=(0.9600)



NOTE: for GTR2 and RACE 07, there are also the RaceRatio and QualRatio values controlling relative speed in the race and quali, respectively. But these are not "globally" set for basically all tracks in the whole game, but must be tuned case-by-case.
 
I use to solve the incorrect braking points (too much braking force) with AI Brake Power Usage="0.74000" but I noticed another issue.
Brake lights "flikering" while braking. Showing terrible USE of the brakes and not realistic. Can be seen at the end of a straight. Is like they are not hard braking and pushing to their real grip limit, and only having too much braking force.
This really affects driving and how they come out of a turn.

Well.. AIBrakingStiffness=(0.74,0.74,0.74) and AI Brake Power Usage="1.00000" solves it for me.

That means the other USAGE values (AI Brake/Corner Grip Usage) need to be also ="1.0" so the AI drives 100% on its capabilities, to be able to mimic a real race driver pushing the on the limits of his tire peak slip angle.

Now.. if AI Brake/Corner Grip Usage="1.0", then this shows that there is also too much grip at Brake/Corner but not at Traction, meaning AIDryGrip=0.74 can not be used for this. Because affects traction also.

If there is not a setting to do this only on the AI tires then: AI Brake/Corner Grip Usage="0.74" might be the best option.

@Speednut357 come here man.
 
Brake lights "flikering" while braking. Showing terrible USE of the brakes and not realistic. Can be seen at the end of a straight. Is like they are not hard braking and pushing to their real grip limit, and only having too much braking force.
This really affects driving and how they come out of a turn.
[...]
That means the other USAGE values (AI Brake/Corner Grip Usage) need to be also ="1.0" so the AI drives 100% on its capabilities, to be able to mimic a real race driver pushing the on the limits of his tire peak slip angle.
Interesting! I have two thoughts:
  1. I think I've read that these settings like Brake Power Usage often have to be calibrated from mod to mod – for instance, what works for modern GT3 wouldn't work for stock GTR2, and neither would work for Power and Glory. What sorts of cars are you racing?
  2. Recall that the AI run on simplified physics compared to the player. Meaning that you don't necessarily want the AI pushing to their "peak" capabilities, because they'd be capable of doing things (especially at higher AI percentages) that you fundamentally are not capable of as the player... which would, in general, be quite frustrating. Perhaps high values near 1.0 are a good idea for some cars... but I doubt it's a good idea always and everywhere.
 
I use to solve the incorrect braking points (too much braking force) with AI Brake Power Usage="0.74000" but I noticed another issue.
Brake lights "flikering" while braking. Showing terrible USE of the brakes and not realistic. Can be seen at the end of a straight. Is like they are not hard braking and pushing to their real grip limit, and only having too much braking force.
This really affects driving and how they come out of a turn.

Well.. AIBrakingStiffness=(0.74,0.74,0.74) and AI Brake Power Usage="1.00000" solves it for me.

That means the other USAGE values (AI Brake/Corner Grip Usage) need to be also ="1.0" so the AI drives 100% on its capabilities, to be able to mimic a real race driver pushing the on the limits of his tire peak slip angle.

Now.. if AI Brake/Corner Grip Usage="1.0", then this shows that there is also too much grip at Brake/Corner but not at Traction, meaning AIDryGrip=0.74 can not be used for this. Because affects traction also.

If there is not a setting to do this only on the AI tires then: AI Brake/Corner Grip Usage="0.74" might be the best option.

@Speednut357 come here man.
It is tough to give you an exact answer of "change this setting to (some value) and said symptom will change."
Most of my experiments are based on Race 07, which has the added difficulty of resetting its PLR file settings every time you start the game. Still, I will try to explain what I have found, and hopefully, we can get some understanding of all our findings.
I originally started to experiment with AI Breaking stiffness in the hopes of reducing how many times the AI would slam into the back of me. Although Initially, it did make a difference, I eventually found that a combination of settings worked much better. The idea I could set the AI breaking point earlier with this setting was a false idea.
The game is trying to calculate the corner speed of the AI, and as you point out, if the calculation is poor, the AI keeps touching the brakes off and on. They are even hitting the accelerator too off and on like a Yoyo. So I think the idea is to make subtle changes to several settings to get better output from whatever the algorithm is calculating. I wish somehow we knew precisely what the algorithm was and what values it uses, but we don't, so we are forced to experiment.
I like a softer ai who doesn't hit me so I can do long races, so my settings tend to be safer. Bear this in mind. Here are some settings I have found to help.

PLR

AI Driver Strength= 90 (In Race07, this must be 90 or AI has limited accelerator)
AI Brake power Usage = 1
AI Brake Grip Usage = 1
AI Corner Grip usage = 0.93
AI Max Load = 32000
AI Min Radius = 0.10
AI to AI Collision Rate= 18
AI Realism = 2

AIW
slowwhenpushed = 0.10
AIDraftStickiness = 1
AI Range = 1
AI Breaking Stiffness = 1.0,1.0,0.9
RaceQualRatio = 1.0005

GDB

AIDryGrip = 1.0 (use this setting to adjust AI speed specifically in corners)

HDC

AIMinPassesPerTick=5

I could go on at length about this setting. The short version is. If you have too many cars in the race and have this setting high, the game will take shortcuts when calculating AI. I think it is some feature to prevent the CPU from taking too long to calculate AI paths. Putting this setting to the max of seven doesn't help much, and if you hit the CPU limit, game over.

You then have all the suspension settings, which do affect what we are talking about. Good mods don't need adjusting in this area. Watch out for good mods and take note of what they put here.

And then the Talent file, which I am still working on, but those settings, believe it or not, also make a big difference. to what you are talking about.

And finally, The AIW path makes a massive difference, and some of us are spending far too much time experimenting with adjustments to the AI lines to improve AI performance.

Yes, I know this is getting very long and complicated. In my mind, It is.


Hopefully, my Rant brings about more discussion. It will take many minds to solve this.
 
One caveat - these are global settings, when you tweak them you are optimizing for the particular car/mod you are using at the time. What works fine for a GT mod may be completely inappropriate for an F1 mod; in fact what works well for GT1 cars may not be optimum for GT3 cars.
I recommend (backup default settings of course), optimizing these settings for the one car/mod, note the new settings, reinstate defaults, interpolate the tweaked settings to modify the car/mod physics. Easier said than done, but now all cars/mods are tuned to a common game setting, rather than constantly tweaking the game to new mods.
 
It's amazing how the impact of AIW settings depends very much simultaneously on other parameters elsewhere in the game.

And then the Talent file, which I am still working on, but those settings, believe it or not, also make a big difference. to what you are talking about.
Yes! Like the Composure values Shovas was tweaking recently.

AI Driver Strength= 90 (In Race07, this must be 90 or AI has limited accelerator)
Is it 90% in RACE 07 where the AI put down full throttle? Not 95%, like some of the PLR file comments say in ISI-based sims? Or does this vary from game to game?

One caveat - these are global settings, when you tweak them you are optimizing for the particular car/mod you are using at the time. What works fine for a GT mod may be completely inappropriate for an F1 mod; in fact what works well for GT1 cars may not be optimum for GT3 cars.
This is true, and sometimes the game engine helps us to optimize things car by car. For example, in rF1, I found this setting in the HDV files for V8 Factor Unleashed:

AIPerfUsage=(1.00, 1.00, 1.00) // PLR file overrides for (brake power usage, brake grip usage, corner grip usage) used by AI to estimate performance - only positive values will override, see PLR for defaults

So the PLR file 'usage' tweaks can seemingly be overridden by these values! Something maybe to keep in mind when tweaking AI. Maybe would be better than tweaking global settings in the PLR?
 
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As with any hierarchy, never go further up the ladder than necessary to achieve your goal.

With AI it is talent>setup>track/physics>plr, any change you make at any level affects all levels below it. Not saying the plr files are sacrosanct, only that we must assume they are/were a good compromise for the default cars, and should be the base for creating mods. You may find fault with a mod when the issue is that it was created with different plr settings than you are using, and your settings were changed because they work better with another mod you are using (and only the mod creators know what plr settings they had when creating their mods; it is rare for a mod to recommend plr changes to match). But it is often simpler to make a quick plr edit than to decipher what to change in a mod for the same effect ...hence I keep the pertinent default plr lines backed up.
 
and should be the base
I totally understand. Once the best PLR settings are found (wich I think I just did), it should be as you said: same for all.
Is it 90% in RACE 07 where the AI put down full throttle?
On GTR2.. Im getting full throttle. Even at kerbs.
AIPerfUsage=(1.00, 1.00, 1.00)
Well something to consider as you said. Not needed I think.
often have to be calibrated from mod to mod
Nothing should change on the "PLR" from mod to mod. Nothing.
Recall that the AI run on simplified physics
I always considered "AI simplified physics" just in case. That is why I try to have everything on AI equal to player. That means a lot of AI values have gone to ="0" or just deleted.
you don't necessarily want the AI pushing to their "peak" capabilities
I believe you can MAKE the AI "push" at a given "peak slip angle". You just dont know were it is.

But Yes, I have noticed the AI can "find more grip" than the player. But it can only be "faster" when it actually "has more grip".
Meaning if at some turns it is (5-10Km/h) faster but at some others it is slower, I would call that a balance, specially considering the AIW files not been the best. But if the difference is like 2.5 secs. faster than me.. he has something more. (under tha hood)
but I doubt it's a good idea always and everywhere.
Again, whatever value I found proper in the "PLR" (with my car/tires/terrain/talent files) it should be go always and everywhere. And it basically will let you know when those "other things" are wrong. But that just me.

@Speednut357
You are almost right with - AI Corner Grip usage =0.93. But =0.9 I found more proper, as I expected.

I knew the original physics were porly done, so it turns out.. yes the AI it is actually "overgripped" at CORNER/BRAKE (but not TRACTIOn) compared with Player.
And this USAGE values seem the only way of decrease that back. Maybe that is why they are there. (Because they knew they were messing things up?).

I use Half Rate="0" and Tire Sampling="1".

My hole car and tyres are not problem right now. Both very polished. But not full.

My talent file is ready to fight but.. there is something hardcoded or.. I have 2 more values to test (actually) and be shure (Crash/Recovery).

The value AIDraftStickiness = 99, 0 or any, does nothing to my non steam-GTR2. Same with AI Breaking Stiffness = (0.01,0.01,0.01) it does nothing. Maybe a syntax error?

So right now my AI is basicly flying and will pass you clean, but he still has some fear of crashing your rear bumper when close. And if he hits a rear bumper he lifts throttle instead of fastly recover.
 

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