GPL: Weird AI problem

Last night I was running a 68 lap race on Monza against the AI. After a couple of laps I wondered what happened to Hill. Mostly I'm driving with Hill and Clark at the front, but now Clark was in front of me and Gurney behind me. I hit f2 and went to Hill's car. He was driving really slow, he did about 2:30 about a lap. I thought he had car trouble and would go to the pits on his next lap. But he drove on. For 43 laps he still drove on, holding up most of the AI drivers. I was very scary to have such a slow car on the track. Numerous times a barely could avoid him. On lap 44, I just overtook Clark, Hill entered the parabolica at a ridiculous slow speed. I had to slow down early to avoid him. Clark rammed me from behind, and all three of us were taken out of the race. This seems to be a bug of the AI. When I went back to the main screen, I saw that Hill was 18 laps behind. Anyone else ever had this experience? Andre

Yes, I have seen something similar, can't remember the details now. I assumed at the time that it is a case of the AI car randomly suffering engine damage. Unfortunately there is no routine in the code to allow for AI cars to decide to pit if the car performance is hopelessly uncompetitive. After all, GPL AI drivers are legendary for there stoicism and persistence, even when they loop their cars, provided they land upright they seem to find first gear and are back on the track without pausing for breath! -- Mark Croasdale ICQ 21549408

<snip> Yes, once at a Grand Prix at Watkins Glen. Think it was Hill there as well. I guess it simulates Hill getting a problem which causes him to go slow, but isn't enough to make him retire. Perhaps a bent susp? /Martin Sent via Deja.com http://www.deja.com/ Before you buy.

: Last night I was running a 68 lap race on Monza against the AI. After : a couple of laps I wondered what happened to Hill. Mostly I'm driving : with Hill and Clark at the front, but now Clark was in front of me and : Gurney behind me. : I hit f2 and went to Hill's car. He was driving really slow, he did : about 2:30 about a lap. I thought he had car trouble and would go to : the pits on his next lap. But he drove on. For 43 laps he still drove : on, holding up most of the AI drivers. : This seems to be a bug of the AI. When I went back to the main screen, : I saw that Hill was 18 laps behind. : Anyone else ever had this experience? Sure - it's no AI bug - the cars in GPL can all suffer failures even the AI cars. Presumably Hill had lost top end revs or had some kind of engine problem. -- Richard G. Clegg Only the mind is waving Networks and Non-Linear Dynamics Group Dept. of Mathematics, Uni. of York www: http://manor.york.ac.uk/top.html

I consider that as a major AI bug: If he's 18 laps behind, being an enourmous hazzard for other drivers, he should really quit. I can't imagine that something like that ever happened during a real race. Andre

I had that experience with RS2? Must be just something that happens

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>Last night I was running a 68 lap race on Monza against the AI. After >a couple of laps I wondered what happened to Hill. Mostly I'm driving >with Hill and Clark at the front, but now Clark was in front of me and >Gurney behind me. >I hit f2 and went to Hill's car. He was driving really slow, he did >about 2:30 about a lap. I thought he had car trouble and would go to >the pits on his next lap. But he drove on. For 43 laps he still drove >on, holding up most of the AI drivers. >I was very scary to have such a slow car on the track. Numerous times >a barely could avoid him. On lap 44, I just overtook Clark, Hill >entered the parabolica at a ridiculous slow speed. I had to slow down >early to avoid him. Clark rammed me from behind, and all three of us >were taken out of the race. >This seems to be a bug of the AI. When I went back to the main screen, >I saw that Hill was 18 laps behind. >Anyone else ever had this experience? >Andre

Are we talking about Graham or Damon now? ;) MRSisson

Edit the gpl_ai.ini file under the [ mechanical ] header. It's in the *:\sierra\gpl folder. mechanical_failure_chance = 0.000000 ; chance in 10000 (!!) per ACTIVE AI car for induced problem/failure each interval Set the value to 0.00000 and this will prevent any of the Ai from dropping out or having a mechanical failure that will drop them from the race or leave them on the track going very slow. I want to pass them because I'm faster, not because they had a problem. DBH P.S. Plan way ahead!!

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> Last night I was running a 68 lap race on Monza against the AI. After > a couple of laps I wondered what happened to Hill. Mostly I'm driving > with Hill and Clark at the front, but now Clark was in front of me and > Gurney behind me. > I hit f2 and went to Hill's car. He was driving really slow, he did > about 2:30 about a lap. I thought he had car trouble and would go to > the pits on his next lap. But he drove on. For 43 laps he still drove > on, holding up most of the AI drivers. > I was very scary to have such a slow car on the track. Numerous times > a barely could avoid him. On lap 44, I just overtook Clark, Hill > entered the parabolica at a ridiculous slow speed. I had to slow down > early to avoid him. Clark rammed me from behind, and all three of us > were taken out of the race. > This seems to be a bug of the AI. When I went back to the main screen, > I saw that Hill was 18 laps behind. > Anyone else ever had this experience? > Andre

Hmm, I think Graham, because if it was Damon, it won't be a bug, but a feature ;))) *gdarvvf* Bye! Crash MRSisson schrieb:

Perfect tip, thanks! Andre On Mon, 25 Oct 1999 10:39:39 -0500, "David B. Harrison"

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>Edit the gpl_ai.ini file under the [ mechanical ] header. It's in the >*:\sierra\gpl folder. >mechanical_failure_chance = 0.000000 ; chance in 10000 (!!) per >ACTIVE AI car for induced problem/failure each interval >Set the value to 0.00000 and this will prevent any of the Ai from >dropping out or having a mechanical failure that will drop them from the >race or leave them on the track going very slow. >I want to pass them because I'm faster, not because they had a problem. >DBH >P.S. Plan way ahead!!

I noticed another weird problem with the AI a few days ago, that is when I'm going down the straight towards the Masta Kink at Spa I just reach the 199mph mark in the Honda, but the good AI (Clark, Hill,Amon etc) reach 199mph about half way towards the Masta and stay at this speed along the whole straight. The annoying thing other than the fact they creep up on me is that when there is a massive chain of AI cars nose to tail behind eachother, they still stay at 199mph, you would think slipstreaming would boost their speed but they stay right on 199mph down the whole straight and their cars aren't even in the redline. This creates boring racing for the fact there are none of those lovely slipstreaming battles that Spa is renouned for. Anyone experienced problems like this before? Is there a fix? Does GPL simulate slipstreaming between AI cars? Just wondering Dan

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> I noticed another weird problem with the AI a few days ago, that is when I'm > going down the straight towards the Masta Kink at Spa I just reach the > 199mph mark in the Honda, but the good AI (Clark, Hill,Amon etc) reach > 199mph about half way towards the Masta and stay at this speed along the > whole straight. > The annoying thing other than the fact they creep up on me is that when > there is a massive chain of AI cars nose to tail behind eachother, they > still stay at 199mph, you would think slipstreaming would boost their speed > but they stay right on 199mph down the whole straight and their cars aren't > even in the redline. This creates boring racing for the fact there are none > of those lovely slipstreaming battles that Spa is renouned for. > Anyone experienced problems like this before? Is there a fix?

Yes, and yes there's a fairly easy fix. Open the gpl_ai.ini file and find the line: rolling_drag_amt (it's towards the bottom under the [physics] header This is a drag coefficient value, and by default it's 0.040. With this low drag all cars reach 199mph, and most do it well before the end of the straight. If you increase it a value of about 0.065 to 0.070, the ai cars will have more drag. The Lotus and Eagles will still reach the limit of 199mph, but further down the straight, while the slower cars won't reach 199 at all. You can also change the limit of 199mph to a higher value so that the Eagles and Lotuses might go even faster than 199mph (particularly if they're slipstreaming). To do this open the track.ini file in the tracks\spa directory, and find the line: dlong_speed_maximum which is under the [GP] header. The value following is the speedlimit of AI cars. It's given as meters per tick with a tick being 1/36 sec. Knowing this you can set the speedlimit to any speed you want, as it's fairly easy to calculate! Oh and please note: this ONLY changes the speed of AI cars, it has no effect on human controlled cars! -- Arne Martin

Not quite the same but a similar disconcerting thing that happened to me when I was trailing well behind almost all the AI in a race at Watkins Glen (I came late to GPL and am slowly improving but am still at the point where 12th or 13th place is a good result :-). Coming round the last lap felt secure in my position so was backing off a bit to avoid a stupid spin when suddenly a green Lotus appeared on my tail trying pretty hard to get past me - I managed to hold it off as I went round the last corners when suddenly I saw it pull down the pit lane. Clearly the AI drivers do not ease off after the chequered flag to coast into the pits! BTW on another AI/race related issue - sometimes in the race results I find I'm classified ahead of some driver who is marked as "suspended" - what is this - did they get black flagged for some infraction? Sent via Deja.com http://www.deja.com/ Before you buy.

<snip> Does it definitely say "suspended"? Or is it something like "susp." which may indicate suspension failure? regards Ian Hill

Aha, of course, it was "Susp" which I interpreted as suspended but now that you mention it suspension failure is the more likely explanation! DeS Sent via Deja.com http://www.deja.com/ Before you buy.

In a race at Mexico against 10 AI, I was on pole and got a reasonable start and led into the first corner with the 2 Loti following. Then, coming out of the left-hand kink exit to that first corner I noticed that the screen update was a bit jumpy - a sure sign of an accident. When I looked at the replay it showed that the 4th car, an Eagle if I recall (I saved the replay it was so bad, but am doing this from memory), had started to slow through the first part of the corner (obviously some kind of early mechanical failure) and it eventually ground to a halt out on the track. However, the car behind and other following cars, had no clue as to what to do and just ended up grinding to a halt also, with various cars just going into the backs of other cars. Then, in order to get moving, some would try and drive in a straight line in a pitiful attempt to drive through the car(s) in front, whilst others ended up at a ninety degree angle to the track and going nowhere. Eventually, some 20 to 30 seconds later, not only was the Eagle out but 2 other cars also. Sad. In many years gone by, on my old Atari ST, I had a go at changing various aspects of the original Microprose Grand Prix, and one thing that I discovered about overtaking on corners was that a pretty simple formula would work. That was, if the car behind felt that the car in front was going 20mph too slow through the current corner and the car behind was in a position to do so then try to overtake. This worked in both slow and fast corners as a starting reference and with some simple tweaking for whether the car ahead was accelerating, braking and some added randomness/weighting it was pretty realistic. Certainly never got the in corner pile-ups that occur in GPL. And in case some people who had the original Atari version are thinking to themselves that it didn't have cars slowing out on the track so this would never have occurred. Well, in mine it did because I had incorporated that feature as well. :-) -- Peter Ives