Flaws of the tyre model simulation

Discussion in 'Gran Turismo Sport' started by Lord Protector, Feb 3, 2018.

  1. zzz_pt

    zzz_pt

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    Or they're not using the default, road variant, tires. It looks like they use either Sport Soft or Racing tires.
     
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  2. Lord Protector

    Lord Protector

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    They do not use stock tyres, these are obviously racing tyres.
     
  3. xBSxChadSpeed

    xBSxChadSpeed

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    I also noticed less rev limiter bouncing than before. Most of the lower powered cars now just hang near redline if you launch full throttle instead of just rapid firing off the limiter. Feels a bit more realistic. It’s still hard to get a realistic launch, I run sport soft tires on N cars. The beasts like the hellcat still are impossible to launch well.
     
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  4. Lancer_R

    Lancer_R

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    Arent all the tyre and bop suppose to be fixed before June 8th Manufactuers as the lancer evo gr3 feels held back. It feels to attached to the track and understeers then slides if anyone knows what i mean?
     
  5. mariodiniz21

    mariodiniz21

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    This physics problem is so annoying in GTS, I don't understand how they ****ed up they physics so badly. The game is playable and enjoyable only until you pass the limits of grip. Every time I try to drift and the car shoots the other direction without a reason I just want to turn off the PS4 and never touch GT again, because it is SO unrealistic, it's also almost impossible to hold a drift during a long corner because the car just loses all the grip and almost stops. GT4 and GT5 were not like this! I could drift for hours in GT5, it was realistic and fun. It's annoying that they had it right and ruined it completely, and I don't see it getting better. I have more than 10 years of experience in drifting and racing in real life, and I've played Gran Turismo since it's original release, and it makes me so mad that after so many years of development PD can make the physics of this game worse and worse, I would normally be super hyped about GT7, but with the physics model they are using at the moment, unfortunately I'm not.
     
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  6. Deadpool

    Deadpool

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    What wheel are you using? I have ZERO issues with controlling oversteer/drifts.
     
  7. Ryan Sandall

    Ryan Sandall

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    I wouldn't suggest this game for drifting tbh,
    Tbf fundamentally for racing I think this game is pretty good it's got all the basics and you can really learn to not overstep the mark, use the grip you get decent feed back as to what's happening

    I'm on T500rs just for reference
     
  8. Jump_Ace

    Jump_Ace Staff Emeritus

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    After playing ACC for a while now, I can see the flaws in the GT tire model. They drop off too fast and you lose too much grip. It feels like the tire model is more of a wide spike rather than an arc of increased and decreased tire traction.


    Jerome
     
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  9. mariodiniz21

    mariodiniz21

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    Hi, I'm playing with the Logitech G29. Don't you notice that the way you have to "recover" the wheel after a drift is so unrealistic? You have to fight the wheel constantly, when I bring the steering wheel back to the center to straight the car, it grips and shoots the other direction, which forces me to correct the wheel the other way, it's not like in real life where you can put the car back straight in a smooth way, without correcting steering the other way. Up until GT5 this did not happen, I noticed this strange behavior started in GT6, where straightway I felt the physics beyond the limit of grip changed for much worse in GT. I believe not everybody will not notice this, and will noot be this picky about this matter, but for someone who's used to drifting it's very noticeable and for me ruins the experience. It was huge fun to drive rwd cars beyond the limit in GT5, it really carried over into real life, but not anymore.

    I want to say though that this is not a GT only problem, some other current games have this too. Like Assetto Corsa, iRacing and Forza (when playing with simulation steering (it's much more realistic with "normal steering")), so maybe it has something to do with a generic tyre/physics model that most games are using right now? Old games like LFS and GT5 had much more realistic physics for example, that carried over to driving over the limit in real life, I learned to drift irl in LFS with a G25.
     
  10. Deadpool

    Deadpool

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    Must be a issue with the Logitech. I don’t have any of these issues with my Fanatec CSL. Oversteer/under are very natural and easy to control.

    Honestly, GT Sport is hands down the best physics in a GT game, it’s not even close. I can balance cars on the limit all day long.

    What force/sensitivity settings are you using.

    EDIT: Another question. Race tires or street tires? Race tires, you can still catch a slide, BUT when they lose grip it’s a cliff. This is like real track tires. You have to be very fast/precise with corrections on race tires.
     
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  11. mariodiniz21

    mariodiniz21

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    I totally agree, GT will teach how to drive fast on a track, it's realistic as it ever was up until you go over the limits of grip and try to drift. And for most people that's totally fine. What bothers me is that it was better in the past, I could drive fast and focus lap times only, but I could also drive over the limit and learn to control and practice/learn about a rwd oversteering, not anymore. in GTS I can still control the car mid drift, but what I have to do with the steering to correct the drift doesn't apply to real life anymore, and that's what annoys me.
     
  12. mariodiniz21

    mariodiniz21

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    I've never tried another wheel so I can't comment, but to me it feels like a physics issue, with the controller it has the same problem. This problem started in GT6, and I played both GT5 and GT6 with my old G25, in GT5 it was great, in GT6 it was not, but only when the car started drifting, up until that both games feel nice and similar, GTS imo uses the same "tire physics base model" as the GT6.

    I've tried a lot of different settings, yesterday I turned force and sensitivity down, makes no difference.

    About the tires question, I usually play with hard sport tires to make the street cars feel more realistic. I know with slick tires the car behavior is less progressive.

    Thank you for your inputs.
     
  13. Deadpool

    Deadpool

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    So odd. It’s literally the exact opposite for me. Must be the wheel/settings you guys are using.

    Id leave force higher 5+ and sensitivity at 10. I can’t speak to the G29, but the fact that it isn’t a issue on the Fanatec setups makes me think it’s wheel/settings.

    It could also be that the Fanatec wheels give us a LOT more customization which works well with the new physics engine. You only can adjust torque/sensitivity right? You want to leave torque prolly higher than 5 on a G29 considering it has half the force of Fanatec. The max Nm on the G29 is around 3Nm I believe, which is significantly lower than what a street/sports car puts out.
     
  14. Groundfish

    Groundfish Premium

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    Tbh GTS does an excellent job of replicating the self centering force felt through the steering rack in cases of oversteer, or also exiting turns letting steering open up.
    When the game was released it wasn’t that way tho. Imo now it works as it should. Very intuitive imo.
     
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  15. Lord Protector

    Lord Protector

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    It’s not an issue with his wheel. It doesn’t matter what wheel you use, physics stay same.

    The truth of the matter is, people with no background in real life racing, even karting at least, these people won’t know what’s wrong with the tire simulations in these games. I don’t want to offend you, but you’re probably one of them if you’re serious with your posts.

    @mariodiniz21 described it perfectly, players should be able to straighten a car from the drift, without sharp in forced inputs, just like it can be done irl. This is not possible in GTS, and I too recall this being possible in GT5.

    btw, the excessive loss of grip is still present in GTS, check 0-60mph times. Still totally off.
     
    Last edited: Jul 2, 2020
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  16. Deadpool

    Deadpool

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    Exact opposite. I have track experience, and the physics while not perfect, are fine. The issues you guys are mentioning, others and myself do not have these issues.

    So it’s either user error, settings/wheel.l, or combo of the two.

    It 100% matters what wheel you use. Sorry but claiming otherwise is ignorance in this regard. With a better wheel you get more information, which allows you to adjust to finer details, just like a real car. With a lower end wheel you lose these details. This is why everyone raves about DD wheels “it’s easier to control oversteer!” being the most common first impression people have. Trying to judge a physics engine on a low end wheel is silly.

    Explain why myself and others have zero issues controlling oversteer or straightening out from a drift. The fact that the rest of us don’t have the issue is proof it’s not the physics engine that’s the problem with this issue they are having. Again, not claiming the physics engine is perfect, but the claims of a inability to straighten out or smoothly control oversteer on limit is grossly exaggerated. It’s not perfect, but for those who can’t control it......it’s not the game.

    Talking about 0-60 proves to me you don’t know what you’re talking about in this regard. 0-60mph in sims is cherry picking and subject to many variables not taken into account. You could take a top sim and have it be perfect in nearly all regards, but 0-60 are not accurate, this doesn’t mean the physics engine is broken. 0-60 is not indicative of a physics engine as a whole simply due to the fact that in the real world we have hundreds and hundreds of different tire compounds, sizes etc. The tire model isn’t perfect, we’re not claiming that by any means. But this specific convo is in regards to controlling oversteer on/at/over the limit, and in that specific regard GTS is wayyyyyy better than any GT that came before it and it’s decently close to the real thing. Actual drifting (the sport) I don’t find realistic yet, but on the limit oversteer is a pretty good and anyone capable of controlling it in real life should have zero issues controlling it in GTS.

    I find a big issue that most have, is not understanding the speed they are going relative to the speeds they are doing in real life. For example if you are used to oversteer at lower speeds, you can’t compare that to significantly higher speeds in game. The two are simply not comparable. Other issue to consider, is drivetrain. FR/MR/RR handle oversteer IRL completely differently. MR is sharper inputs IRL, FR is far smoother.

    Hopefully GT7, with the extra power of the PS5, can devote more resources to the physics engine. The FFB while much improved, still has a ways to go with catching up to say ACC/Rfactor etc.

    The twitchy on limit feel I found to be a far bigger issue in prior GT’s and not as smooth/natural as it is now (still not perfect).

    No issues with real life oversteer on track here. Old 73RS replica, lovely lil thing.
     
    Last edited: Jul 2, 2020
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  17. Galverstoney

    Galverstoney

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    If im understanding it right, the grip falls off excessively in this game? What is the tl:dr?

    It's not realistic because the cars slide too much?
     
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  18. Groundfish

    Groundfish Premium

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    This.
    I’m looking forward to what the new hardware will bring in terms of physics/ffb, but that’s not to say that GTS is not basically sound in these areas.
     
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  19. Deadpool

    Deadpool

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    Agreed, it’s not “broken”, but it does need some polish. And different wheels will respond very differently to a physics engine, I find the Logitech etc lack the subtle feel, which you need. Without it you’re just responding to visual cues, which is too late and can result in the twitchy feel some mention.
     
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  20. mariodiniz21

    mariodiniz21

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    where the drifting feels more realistic to me is on dirt (low grip) tracks, that's where the oversteer feels totally natural.

    on tarmac (high grip) the tire model is flawed
     
  21. VBR

    VBR Premium

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    I don't have many gripes with the tyre model nowadays. My main issue is with the different steering ratios between cars, & the understeer vibration effect (both of which are sadly game killers for me personally). I think the improvements in tyre physics over the years has left them in a better state than at launch & the same goes for the FFB, though neither are ideal or on the level of something like AC.
     
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  22. Moon_k

    Moon_k

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    I don't have lots of problem with the tire model, I've had some other sims where the car stalls out of the blue for exceeding the tires grip for a short moment as if the tire just didnt didnt gripped anymore. On GT-S you can exceed the limit for a moment and the car won't suddenly stall and you wont lose alot of time for doing that and feels more natural that way for me.
     
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  23. Sharpie

    Sharpie

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    I would use fiat 500 in that situation :)
     
  24. ShiftingGears

    ShiftingGears

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    I'm sure others can explain it but it feels like the issue to me is not so much the tyre model but that theres no proper weightiness to the cars - for cars with softer suspension it doesnt feel organic.
     
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  25. meekrab

    meekrab

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    The G29 wheel is also significantly smaller than any real sports car steering wheel, so the lesser motor torque balances out against the lower leverage the driver has. I know it's capable of giving a lot more resistance than my '06 GTO ever did, for instance.
     
  26. Granadier

    Granadier Premium

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    The tire model suffers from a fundamental inability to simulate multiple zones of grip within the tire itself. GTS simulates the tire as a whole unit, and based on experience the grip that is applied to the tire is calculated based on a the lowest grip value that the tire collider is in contact with. (I believe iRacing does it the same way whereas ACC has a much more sophisticated grip calculation)

    This means that when grip is lost anywhere on the tire contact patch it is lost entirely across the surface of the tire. There is no in-between. This is most apparent when a tire touches a spot of low grip such as grass, sand, or curbing. Even a single pixel of contact will cause the entire tire to drop all grip levels when in reality a car would only be marginally affected until the tire has lost contact with the road enough to cause a large enough loss of grip.

    You can see this when cornering and touching a bit of grass. Or when you hit one of the many "phantom" curb glitches on tracks like RBR and Catalunya where the curb disappears and the tires traction vanishes.

    Hopefully this is rectified in GT7.
     
  27. Deadpool

    Deadpool

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    The smaller size also amplifies movements which could cause people to over correct vs what they are used to in a street car. I have this issue with my F1 wheel in the rain with street cars, it’s a lot twitcher than a round wheel.

    When I said sports cars I was referring to higher levels. GT3’s, Vettes etc. But you can prolly boost the strength to be higher for basic steering input which is too strong and unrealistic. You want the higher force in the curbing/bumps. Getting a good feel for turn in is tricky. I’m starting to test drift settings up to -2. I dislike the lack of response it gives in transitions, but for say the F1500 OT feels great. Some cars I’m liking -1, or Porsche’s I like Off. But off in say the F1500 is rather dead at turn in. Very vague.
     
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  28. Groundfish

    Groundfish Premium

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    I finished top twenty or some such in that car under bop at Brands.
    The big issue I found was braking late enough and timing that such that the stiff suspension was loaded on turn in, plus once you start winding steering to apex the slightest unsmooth movement unsettles it.
    I spent all week on that car that race. I found it very tough to get the timing right...brake too early...cars suspension not loaded...no turn in. I really had a hard time with it. I’m sure I couldn’t do very well right now without 3-4 hours practice.
    Stiff car, not much travel, plus overslow it and kiss downforce goodbye.
    That’s a tough car to drive well. One of the few I don’t use tcs. Weak abs was also better.
    Tons of people complained about that car that week but I went OCD out strungout like a research monkey every night lmao.
    I haven’t tried dri negative in a long long time but now you’ve got me curious since the games evolved over time and updates...
    LeMans next week c race!
     
  29. Deadpool

    Deadpool

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    It’s def a tricky car. I’m in a small league which uses penalties, ive accrued a 65% penalty lol. I think my weight was 138% and power at 72%. Made it easier for corner exit but also pushed more. Tuned the hell out of it though. Its a fun balance of aero and mechanical grip.

    I wasn’t expecting to like -1/-2 drift but in some cases it’s pretty nice. The best would be the ability to combine -2 and off. Give us -2 for initial turn in weight, but off for transitions. For the Lewis challenge I’m running -1 on the Merc at Suzuka. Slight delay going through the S’es. I’m still on the fence. Might go back and forth with testing.