People have expressed interest in Gran Turismo as a simulator, and some
have indicated that the AI cars are reasonably good. I suggested that,
at lower levels, it is not so good because the cars try so hard to let
you win. I thought people might be interested in more detailed
qualifications.
First off, Gran Turismo has "Arcade Mode", and "Simulation Mode".
Forget about Arcade Mode; it's useful for learning the general layout
of some tracks, but not details (all bumps are exaggerated in Arcade
Mode). And the races are all two-laps, and the AI is of the pesky
and bothersome variety.
Now, in simulation mode, Gran Turismo makes you do a lot of work before
you can race the races a simulator aficionado will consider "good".
You must earn three "licenses"; B, A and IA, by passing a set of 8
tests for each. The IA tests actually take over a minute for each
trial, because you must complete a whole lap, in an untuned car no
less. In addition, you must earn money (Credits) to be able to
afford to buy cars and tune them. You start with Cr10,000 which
lets you buy used cars only. A '93 Civic 3dr si is a good initial
choice. You then race the dreadful Sunday Cup a few times to get
cash to improve it so you can win the Clubman or GT cup, and buy
something better to enter other races where you can make real money.
The series with the best remuneration is the "Normal" series, which
simulator aficionados may hate because you can use only "untuned"
cars in it. A Dodge Viper does well here, but it's an hour or so's
worth of well timed exaggerated slides to earn up to Cr400,000--about
enough to build up a car good enough to enter the good races.
Another approach it to take a really fast tuned car (or cheat and take
a racing-model) to the fifteen-minute "MegaSpeed Challenge", and get
close to Cr100,000 for fifteen minutes work.
If you have a GameShark PlayStation, ahem, "enhancer", GameShark web
sites will show you how to patch around all that, but an easier
solution would be to obtain the Winter 1998 Playstation Underground
Jampack CD which has a memory card download which gives you all three
licenses, a garage full of interesting cars, and about Cr2,000,000,000
of simulation money. That turns the game from a sort of "role-playing
driving game" into more of a pick-and-choose simulator. The CD
packaging for the Underground Jampack CD does not explicitly indicate
the presence of the particular download. If you have a friend who
already has downloaded the CD, you can copy his memory card. There
might be a copy DexDrived to the Web somewhere, but I can't find it
off-hand.
The Gran Turismo Manual gives the following ratings for its various series:
From the Manual (but from memory) facts my semi-editorial comments
|--------------| | | V V V V
Sunday Cup - beginner (3 2-lap races; granny's Pinto could win)
Clubman Cup - intermediate (3 2-lap races, good cars, or light tune)
GT Cup - intermediate (4 3-lap races, hard-tuned cars)
GT World Cup - advanced (6 3-lap races, featuring racing models)
FF Series - intermediate (3 2-lap races, front-wheel drive only)
FR Series - intermediate (3 2-lap races, rear-wheel drive only)
4WD Series - intermediate (3 2-lap races, four-wheel drive only)
Lightweight Series - intermediate (3 2-lap races, "lightweight" cars only)
USvsJP - advanced (5 3-lap races, featuring racing models)
UKvsJP - advanced (5 3-lap races, ")
UKvsUS - advanced (5 3-lap races, ")
Megaspeed - advanced (3 3-lap races, for really fast tuned cars)
Normal - professional (5 5-lap races, no modifications allowed)
Tuned - professional (5 5-lap races, no racing models allowed)
Grand Valley 300km - professional (1 60-lap race, with tire wear)
All-Night I - professional (1 30-lap race, with tire wear)
All-Night II - professional (1 30-lap race, with tire wear)
But, even with my semi-editorial comments, that doesn't give the whole
story. Competition in the GT-World Cup is noticeably "stiffer" than in
the USvsJP(etc) series, and individual races in each series exhibit
different competition characteristics. E.g. USvsJP AI seems to start
strong and end a bit weak, while UKvsUS starts a little weaker and ends
a bit stronger. Many series allow you to cheat an enter a racing-model
which generally totally dominates.
Essentially, any but the "professional" races seem to have a noticeable
"handicap" algorithm which causes the AI cars to wait for you. This is
very encouraging when you first begin. 8-) The algorithm is such that
it gives more help to powerful cars with good acceleration. This at
least allows you to set challenges by gradually using weaker and weaker
cars in those series. But, in general, it gets annoying after you've
mastered it.
In any but the "professional" races there seem to be two speed
thresholds for each race. Achieve one speed, and no car will attempt to
pass you, but they will stay right behind you. There is another
threshold you must achieve in order to start leaving the cars behind.
This has the unfortunate effect that if you are driving between the
thresholds, discretion is really the better part of valour because,
unless you are trying to set a personal best, you are better to take a
tricky corner slowly and safely rather than take a little risk to go
faster; unless you pass the second threshold, that same car is still
going stay the same time behind you. And, as I indicated earlier,
if the cars get ahead of you, they slow down noticeably to wait for
you. Study the GT or GT-I Cup demos in the "Replay Theatre" and
you can see this effect. Also notice how, to make a good demo, the
Viper driver in the GT demo deliberately scrubs off speed on every
corner so as to avoid leaving the AI cars behind).
Anyway, I've not seen a lot of other examples of AI cars, so in some
sense I'm talking abstractly. But I can see a lot of good things in
the AI cars in Gran Turismo. They really do seem to be governed by
the same physics model you are (but of course AI finds some things
you find difficult to be easy, and vice versa). That is very good.
Contrary to game reviews based on perfunctory playing of the game,
the AI cars do make mistakes, both small and large. This makes things
very exciting at times. Perhaps the two best races in the game are
the penultimate races in the "Normal" and "Tuned" series; at
"Deep Forest Racing Way ii (reverse)" in Normal, and "Autumn Ring ii"
in Tuned. In the Normal Series, an AI Honda/Acura NSX usually
dominates, especially at Deep Forest, but at turn 4 (assuming the
preceding high speed bend is turn 3), just before the first tunnel, it
often enters too fast and loses control and time as it slides wide. It
will do this in a reckless bid to pass you, and also when it is ahead.
So you cannot take your driving cues from him; you must drive your own
race and hope to take advantage of a mistake like this. (Once I bumped
the NSX off-course on the very first turn, and it got stuck behind the
other star, a Toyota TRD3000GT, and finished an unusual 3rd. I watched
the whole replay, and, sure enough, the NSX had tried to pass the TRD
at that corner, but flubbed it).
In other places, the AI cars make mistakes in fine details of their
line, usually when exiting slow corners. In contrast, they dominate
most fast corners since their AI allows them to explicitly calculate
the optimal speed to reduce slippage. Exceptions are corners where a
drift works really well, and, also a particular fast corner after them
main straight of the two reverse "Grand Valley" courses. This corner
does not suit heavy drifting, but they seem to generally take it even
slower than is reasonable for driving--this might have been done
deliberately since, even so, early in my playing I found it very
daunting how deeply they did go into this corner before braking.
I made it a bit of a mission to learn that corner intimately, actually,
so maybe that's why my "I" is now better than their "AI". 8-)
The only time the AI driving seems unrealistic is when some "alarm"
seems to go off and they decide it is time to pass you. On some
corners this is done nicely. At turn 4 (assuming the first slight
esse is turns 1+2) at Autumn Ring ii, the cars will often nicely
go by you on the inside as you enter a little too late and wide.
But at other times they just sort of force their way around your
outside, often ignoring any contact with you unless you manage to
nudge them clearly off onto the sand or grass. That is somewhat
aggravating. Before my skill developed, or when I tried slow cars,
I had seen this happen at all levels of racing.
So, both the Normal and Tuned series provide quite a nice challenge,
and also the GT World Cup (abbreviated GT-I). While the Normal Series
is dominated by one car, forcing you to win almost all races in order
to win, the Tuned Series is not so dominated, and this allows you the
challenge of holding things together in one race to gain second instead
of falling to fourth, so that you can win the series with 30 of a
possible 45 points. (In contrast, in the Normal Series, you can really
only afford to lose one race, so need to risk more to chance first--but,
in general, the Normal seems "easier" than the "Tuned"). All three
series end with the challenging but silly "Special Stage Route 11"
course--a night time maze of twisty passages, made doubly silly by the
fact that you, as a human, can cheat your way far ahead of the AI cars
once you learn that you can get far far ahead of the AI cars by making
severe use of walls. Slide gently into them and accelerate while
pulling off them--much faster than taking the corners properly.
Similar techniques can be applied at the two All-Night 30
...
read more »
> Oh well, I seem to have rambled on and given an idea of the flavour of
> Gran Turismo, describing things I perceive a racing simulator
> enthusiast would like to know, but did not really stick to my stated
> topic of discussing the Gran Turismo AI.
Now you went and made me dust off the Negcon. Grand Valley here I come (I
have to admit I only did GV300 once).
--
Anssi Lehtinen
