My theory on how GT5's AI may work ~~~Long Read Ahead~~~

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Furinkazen

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This is originally from another topic but the post appeared completely ignored. Its my explanation of how GT5 AI reacts and why it does so...











I got my own theory on GT5 AI.

I have an age-old PC sim NASCAR Racing 2003 Season, and for each track you can edit AI just by changing their settings via simple numbers in the file for each track (drag, fuel use, etc..), but a couple things made me think.

There is a file called "AI_line_modifier" and this affects how AI react. At 1.0 they drive the line that they are primarily programmed to and generally race pretty clean and neat without incident. However if you raise the number they become more aggressive, hunting for line's and basically becoming a lot more aggressive. However this require more grip and they often make more mistakes and crash a lot more because of it.

On the flip side if you turn it down to something like 0.9, they become more conservative, they hold their line and rarely move, even when coming up on traffic 30mph slower. Deleting this line entirely does a bit of both, as they are free to pick where to go and this strikes a good balance.

This makes me think that GT's AI almost has a similar principle. In A-Spec, where AI has not been tweaked much, and the Seasonals, AI is heavily scripted, like it is running a regular conservative line (much like the 0.9 value I mentioned above). This is why it can be so zombie-like at times with regards to where they are, they are so focused on holding their line, they are reluctant to let it go or end up in trouble, hence the conservative approach.

The opposite can be said of Arcade mode, with aggression 10, it's still on rails but it's definitely turned up, AI will try and run around you, but only if they can't hold their line. Basically the AI in GT5 appears almost set to be on their own race and track, oblivious to the player.

The major question is, does GT with its complex physics engine have it in it to have more dynamic AI, like when I mentioned my AI on my NR2003 sim without a modifier? Could it withstand AI freely able to make their own calculations and decisions? The answer is partially yes and no.

Yes in that B-Spec, drivers are more dynamic with pace changes and overtaking, but that is expected by GT5's engine. When you give a B-Spec driver the command "Speed up" that gives the driver AI a set parameter to speed up to. Whereas with the player in A-Spec, the AI does not know what the player will do and cannot adjust accordingly, hence the simplified AI structure. After all, a human player cannot have it actions predicted by a computer program, which has its set limitations.

(Now, did that make any sense?)
 
Yes, it does makes sense... i've seen some other PC games that work on the same principle. A game that I used to mod in the past (SLRR) had 2 parameters, one for how close the AI follow the path line thru the track (the best racing line) and other parameter that defines the agressiveness.

I've been doing some A-Spec races again and some feel better now after those updates, La Festa Cavallino and the Gallardo Race are 2 good examples, if you use stock cars like the AI or light tuned ones. I like to do the Schwarzwald Liga B (the one with powerful german cars), even if it always have 1 or 2 rabbits (usually E60 M5, Merc SLS and Audi R8) try doing it with a tuned BMW 135i and you'll have a good fun.

If you keep your car tuned in the same level (sports tires, etc) you'll have a pretty enjoyable race.

Before the usual people come around saying that it's crap, I tell you to pick a stock F430 or a stock Gallardo and do the races I'm talking about.

The thing is, as A-Spec is a somewhat boring experience, people simply forget about it after completing the events. OFC it's small and it's a shame it's not the size of GT4 A-spec but you can still have some fun.

Now the seasonals, its weird: Some races can be a bit of a challenge, some others are just the same easy and boring thing. Again, I'm talking about my experience using cars tuned according with the cars used by the AI. If you use your 800hp Nissan GT-R with racing slicks, it'll be too easy.

And what is really annoying is the fact that a simple tuning on the A-spec races limitations could transform the average/bad experience into a better one. If you had strict tire and power restrictions and the PDA built into them it would be a different story. I bet the Sunday Cup in a 120hp FF car with Comfort Softs would be a greater experience. It's so simple: the game should make the restrictions, not us.

Those restrictions, with the Arcade mode level 10 AI would be great.

Another thing I've noticed is some mistakes the AI do after the last updates that messed around with it. I did a race on the MR Challenge @ La Sarthe and a McLaren F1 just had a beautiful accident, rear tires on the grass and had an awesome spin. I even took pics of it, will post them here later. This confirms what you said about them being more agressive and having some accidents in the later more "difficult" races.
 
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Hard to really know

If GT's AI could be programmed to be more aggressive, the human drivers might get irritated after getting dive bombed a couple of times. Maybe PD thinks we would rather race against predictable passive AI instead of aggressive AI that blocks and dive bombs you
 
Hard to really know

If GT's AI could be programmed to be more aggressive, the human drivers might get irritated after getting dive bombed a couple of times. Maybe PD thinks we would rather race against predictable passive AI instead of aggressive AI that blocks and dive bombs you

The B-spec Bob's behave a little bit like this. Some other day I was testing if normal AI could get irritated but couldn't find this. :(

http://[domain blocked due to malware]/instances/400x/23014985.jpg
 
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Furinkazen
This is originally from another topic but the post appeared completely ignored. Its my explanation of how GT5 AI reacts and why it does so...

I got my own theory on GT5 AI.

I have an age-old PC sim NASCAR Racing 2003 Season, and for each track you can edit AI just by changing their settings via simple numbers in the file for each track (drag, fuel use, etc..), but a couple things made me think.

There is a file called "AI_line_modifier" and this affects how AI react. At 1.0 they drive the line that they are primarily programmed to and generally race pretty clean and neat without incident. However if you raise the number they become more aggressive, hunting for line's and basically becoming a lot more aggressive. However this require more grip and they often make more mistakes and crash a lot more because of it.

On the flip side if you turn it down to something like 0.9, they become more conservative, they hold their line and rarely move, even when coming up on traffic 30mph slower. Deleting this line entirely does a bit of both, as they are free to pick where to go and this strikes a good balance.

This makes me think that GT's AI almost has a similar principle. In A-Spec, where AI has not been tweaked much, and the Seasonals, AI is heavily scripted, like it is running a regular conservative line (much like the 0.9 value I mentioned above). This is why it can be so zombie-like at times with regards to where they are, they are so focused on holding their line, they are reluctant to let it go or end up in trouble, hence the conservative approach.

The opposite can be said of Arcade mode, with aggression 10, it's still on rails but it's definitely turned up, AI will try and run around you, but only if they can't hold their line. Basically the AI in GT5 appears almost set to be on their own race and track, oblivious to the player.

The major question is, does GT with its complex physics engine have it in it to have more dynamic AI, like when I mentioned my AI on my NR2003 sim without a modifier? Could it withstand AI freely able to make their own calculations and decisions? The answer is partially yes and no.

Yes in that B-Spec, drivers are more dynamic with pace changes and overtaking, but that is expected by GT5's engine. When you give a B-Spec driver the command "Speed up" that gives the driver AI a set parameter to speed up to. Whereas with the player in A-Spec, the AI does not know what the player will do and cannot adjust accordingly, hence the simplified AI structure. After all, a human player cannot have it actions predicted by a computer program, which has its set limitations.

(Now, did that make any sense?)

:bowdown:
 
Imho the a.i are acutely aware of your position relative to them regardless of settings or game mode. All that changes is their reaction to your presence.

In a-spec and seasonal events, the a.i will concede a position in a ridiculous fashion if you so much as look like you might try to pass. Lifting completely and basically just not accelerating until you're well past.

In arcade mode they are much more reluctant to do that, but they still adjust their position when they have to.

For me their awareness is nowhere near as big a problem as their basic lack of speed, odd line irregularities, and poor judgment of positive road camber.
 
PD needs to adjust something..Cause racing in GT5 is more boring than sitting at work. Yes, i have more fun doing my job than racing in GT5.
 
GT6 must have completely rewritten AI otherwise the sense of competition will be as agonisngly absent as it currently is. I feel I am in a procession as opposed to a race. I have said before that GT could learn from NFS Shift 2 Unleashed in this respect. It has an impression of battling for positions that GT has never possessed.

I reiterate what I said several times which is that I would pick an overhauled AI model before an overhauled circuit creator.
 
.... In A-Spec, where AI has not been tweaked much, and the Seasonals, AI is heavily scripted, like it is running a regular conservative line (much like the 0.9 value I mentioned above). This is why it can be so zombie-like at times with regards to where they are, they are so focused on holding their line, they are reluctant to let it go or end up in trouble, hence the conservative approach.

I'm not even sure we can use the word 'conservative' when describing the line these guys run. "Amateur" or "first day behind the wheel" is probably more appropriate. In these modes they can sometimes suprise you with a move that makes it clear that they know you're there, but most of the time they will just come all the way across the trackwidth and slam into your side, as if you have disrespected their family- but you haven't. They are just clueless and a bit pathetic. The worst part about the A.I. in A-spec is the parking. I just had a Ferrari F10 let completely off the throttle before a turn when I was about 3 carlengths behind, he stayed completely off the throttle through the turn as I breezed by, and then remained off throttle until I was about 5 carlengths ahead on the straight. This is not an exaggeration- I am being nice with that description and may be giving him a carlength each way. This is appalling.


.. The opposite can be said of Arcade mode, with aggression 10, it's still on rails but it's definitely turned up, AI will try and run around you, but only if they can't hold their line. Basically the AI in GT5 appears almost set to be on their own race and track, oblivious to the player.

I don't agree that Arcade mode set to 10 aggression is the opposite of A-spec. It is a good bit different, for sure. But the A.I. are still taking amateur lines, hitting the brakes way too early, not getting on the throttle early enough, not smooth with their inputs, and making identical mistakes, one by one, as they plod around the track. Certain corners on nearly every track will be taken painfully slowly (Eau Rouge, anyone?) every lap without deviation! They may have much better awareness of you, and also will make a few racy moves to pass, but major problems remain. We as players looking for a challenge must find that perfect detune that allows us to be fairly even on straights, and then choose slippery tires that will make us more even with them in the corners. Even then, on those certain corners where they have been programmed by a donkey named eeyore to be extra sad... we're gonna have an advantage that just can't be detuned away.

:indiff:


The major question is, does GT with its complex physics engine have it in it to have more dynamic AI .. ?

I believe a much more important question exists: Why, in the credits of GT5, does there only exist TWO A.I. programmers?

Atsushi Hayashi and Yutaka Ito. These two guys need some freakin HELP, man. 'Car Modeling' shows about 50 people in the credits. Now, cmon!

👎
 
The B-spec Bob's behave a little bit like this. Some other day I was testing if normal AI could get irritated but couldn't find this. :(

That's literally the funniest meme I've seen in my entire life. I'm dying of laughter. :D
 
Hi
Your explanation makes sense.
I would prefer that PD spent more time on the AI then on the graphics for GT6.
Having raced online the offline experience is now dull.It is just a procession, no matter how much you reduce your settings to.There is not the feel of real racing, the AI rarely race/overtake each other let alone you.So it feels like a time trial rather then a race. can you overtake all the cars before the end.

Here's hoping they can improve the AI for GT6.

P.S. TOCA on PS1 and PS2 "felt" like real racing.
 
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