Physics thread

Discussion in 'Project CARS 1' started by LVracerGT, Feb 28, 2014.

  1. Animera

    Animera

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    It's really hard to know what's happening in the video's without knowing how you've set up the car.
    All of those seem to me that you've gone in just too hot, or you're running very low rear downforce.

    Something I had to learn very quickly with PCARS was that all the 'go faster' techniques I had learned in GT didn't work in PCARS. Whether that's realistic or not I don't know, as I have no real life racing experience.

    Like any racing game, once you learn it's particular 'quirks', these things happen way less and become predictable.

    When I started playing PCARS I was also spinning and struggling to catch the car when mishaps happened, but now I can throw cars around, induce and catch slides, while knowing what the car is doing.
     
  2. Saidur_Ali

    Saidur_Ali

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    Looks like driver error to me. All four look predictable and saveable. It looks to me you are putting in too much steering input and haven't got a good read on what the cars doing so reacting too late to oversteer situations and exacerbating through your application of throttle, braking and steering. What might help you is reduce front downforce and lower brake pressure in setup but it would be better to understand why the car is out of control and react better. Maybe something in steering wheel settings could help improve feeling?

    Personally I've always found pCARS really easy to drive and to understand what is happening with default FFB on G27. You can attack the kerbs a lot and get away with it. Here is a lap in a GT3 car with stock setup on Monza track:

     
  3. Speedster911

    Speedster911

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    That's pretty much spot on. I have given the game many tries, experimenting with a WHOLE variety of controller settings after checking several forums... but the game's physics are wrong once your car goes into a spin - it's as if there's a giant hand pressing down hard on the car that doesn't let you recover... as you and the other fella pointed out, the front end just goes numb and cars do not react going over curbs the way they should.

    I haven't played the game since and very desperate to sell it off!

    IMO, Forza 5 and 6 have a much more direct and predictable feel. You definitely feel connected to the tarmac and weight transfer is done well, as is off/on throttle response, including car behavior over curbs.
     
  4. Wolfe

    Wolfe Premium

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    The physics engine definitely gets sketchy sometimes when you go up on two wheels or become airborne, so I avoid tall bumps like those at Monza. Just today I pulled a stoppie in the Ruf CTR over Quiddelbacher Höhe on the Nordschleife, which probably shouldn't have happened the way it did.

    Wicked snap oversteer sounds like what I encountered when locking the brakes in some cars. I wasn't satisfied with how well I could modulate the brakes without ABS on the DS4, so I opted for ABS. I was pleased to find that it prevents that sudden bite yet doesn't completely eliminate braking oversteer (like entering the first corner of Ruapuna ass first in the CTR, for example :) ). Trail braking is also possible.

    What I've found with oversteer recovery is that cars lose too much speed from skidding sideways, which contributes to curve you toward the inside wall without enough velocity to recover. Adjusting the steering ratio has helped me when I need more or less steering lock to catch oversteer or tame a tendency to overcorrect.

    I can empathize about the rough edges to this game, like the occasionally unpredictable curbs, or especially the way cars stick to each other and quit steering when they collide. The game does itself no favors with its default controller/FFB settings, default setups, and unhelpful menus to sort it all out. But overall I'm impressed to count it as a proper sim, with its own imperfections like any other. The fundamental dynamics of understeer and oversteer aren't quite right, but to me it's in the ballpark. Somewhere between Enthusia and Forza, with more gritty details than EPR.
     
  5. Scaff

    Scaff Staff Emeritus

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    I would agree that the physics can get interesting when up on two wheels (the AI in particular)...





    ...however in regard to riding curbs and not being able to catch oversteer I still believe this is more of an input issue than a physics issue.

    A couple of old videos to illustrate what I mean. The first is from a five lap hotlap challenge I did with a few friends a while ago, set the quickest clean lap (by PCars standards - I wouldn't call them clean) with no aids used at all and with cold tyre on 'real' wear.



    Lots of curbs ridden and attacked heavily with no more issues than I would expect.

    Now catching slides is arguably less accurate, but race tyres are snappy so that does need to be taken into account, however its still possible.



     
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  6. Wolfe

    Wolfe Premium

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    Curbs are seldom a problem for me, but I have had instances of a curb kicking me sideways without warning, and not because I spun up a driven wheel or made any sudden moves with steering. One time I was in the Audi R8 GT3 at Spa, and a flat curb suddenly snagged and spun me 90 degrees in a split second. It seemed like a glancing collision with the curb, like how those Formula Rookies collide with the track surface once they get up on two wheels.

    As for catching oversteer, some racecars just don't offer enough steering lock for wide slides, even with the tightest steering ratio, as I found last night while experimenting with the E30 M3. By contrast, the Radbul MX-5 proves the physics engine will let you catch and hold very high angles with enough steering lock (as the ultimate test for my latest DS4 settings, I found I can just about drift that thing). Roadcars like the 1M or CTR are driftable with a controller, more easily than I had expected.
     
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  7. Earth

    Earth

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    Well I have to come back here and eat crow, sort of

    I gave the game one last chance and took the advice to boost the rear downforce with a R18 @ Lemans. I also raised the ride height, and got rid of all the camber and toe looking to produce a neutral handling car.

    Im now able to correct oversteer. The transition from oversteer to understeer and vice versa feels far less abrupt and much more predictable. I can feel the edge and when I cross it and crash it feels like I simply went over the edge instead of a bug or glitch doing me in. In other words crashes now actually feel like human error on my part. Its easy for me to look back and identify what I did wrong.

    So I got to experience the most satisfying and realistic physics in my experience with sims at Lemans. It was alot of fun.

    I still feel the issues I've experienced earlier are in effect bugs but you can get around them with a better setup
     
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  8. Wolfe

    Wolfe Premium

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    @Earth -- I'm glad you were able to sort it out. The PCARS Setup Database is a good resource to keep handy; it has provided me with new "default" setups for several cars that needed a total overhaul. I know how to tweak a car when it needs a little of this or that, but I'm not inclined to spend the time deconstructing some of these messes SMS left us with. The database has helped me a lot.

    For the Ruf CTR, Jussi's OEM-spec setup plus my own tweak to the tire pressures was enough to pretty much completely tame the car and allow it to handle more believably. Accurate factory values, what a concept! What's notable is that the author, Jussi Karjalainen, has apparently been recruited by SMS as a Handling QA Lead for PCARS2. That gives me some hope for the sequel with respect to car setups. :tup:
     
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  9. Speedster911

    Speedster911

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    I can't drift to save my life in PCARS! Even though in the Forza games on sim steering, it's easy to learn and get accustomed to. Looks like I'll follow through with the link you provided in your next post and experiment with car setups... if I ever get around to reinstalling CARS that is!
     
  10. Wolfe

    Wolfe Premium

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    I've been driving the 1M with its default setup. I know every person who shares their controller settings says, "zomg this fixed everything!" but I'll share mine if you want to try them. I've also saved this as a reference for what exactly the settings do (as best as I could figure out):
    Input Mode: 3
    Assists: ABS ON
    Code:
    Steering Sensitivity:   25
    Throttle Sensitivity:   45
    Brake Sensitivity:      45
    These sensitivities control analog linearity.
    0-49 is slower near the center/low end and faster at the end of the axis.
    51-100 is faster near the center/low end and slower at the end of the axis.

    Code:
    Speed Sensitivity:      50
    Filtering Sensitivity:  50
    Speed Sensitivity controls the maximum steering lock based on your velocity.
    Higher = less steering lock at high speeds.

    Filtering Sensitivity controls the maximum rate (speed) of steering.
    0 is fastest, 100 is slowest.

    Code:
    Advanced:                  ON
    Soft Steering Dampening:   ON
    Visual Filtering:         OFF
    Opposite Lock Help:       OFF
    Soft Steering Dampening helps soften sudden inputs, like a flick of the analog stick.

    Visual Filtering affects the cockpit wheel/driver animation, making it smoother and more "realistic". When turned off, it reflects your actual steering position in real time, like in telemetry.

    Opposite Lock Help boosts countersteer input to catch oversteer more quickly, but it does not prevent you from overcorrecting.

    The last changes I made were to bump up the steering sensitivity from 0 to 25 and reduce speed sensitivity from 65 to 50, then turn off opposite lock help and increase filtering sensitivity from 30 to 50.

    Adding linearity to the steering axis allowed more precise control of larger steering inputs, which meant I could loosen the speed sensitivity limit and access more countersteer, which allowed me to turn off opposite lock help and slow down the steering rate, making everything smoother.
     
  11. Speedster911

    Speedster911

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    This helps.. appreciate the input! :tup:

    Next objective: muster up the motivation to reinstall CARS :cool:
     
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  12. Matej

    Matej Premium

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    How would you compare PCARS to Enthusia Professional Racing? Every time I look at one of PCARS replays, cars act strangely when they're supposed to oversteer.
     
  13. Wolfe

    Wolfe Premium

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    @Matej -- Refer to this post for an early impression and direct answer to your question, and this post after I spent more time with the game. :cheers:

    Oversteer is a weakness in PCARS1, but the manner in which you can initiate it and control it -- or fail to recover -- is better than what you get out of most other sims, in my opinion (physics-wise, independent of the somewhat crude analog stick steering). For me, the inaccuracy is not so much of a hindrance to enjoying the game compared to other sims.

    I can't perceive the car's mass or center of gravity like you can in Enthusia, and it all feels somewhat "artificial" like a Forza game (or any ISImotor-derived game, which PCARS basically is) when compared to Enthusia or Live for Speed. However, in broad strokes, cars mostly react the way I expect them to. You can steer well-balanced RWD cars with the throttle, and FWDs can kick sideways when provoked or on cold tires. The few AWD cars behave very strangely, though; they're impossibly easy to manhandle around a circuit thanks to the odd flypaper-like behavior at high slip angles.

    It will be interesting to see how much PCARS2 can improve upon this, and just a bit ago I found an excerpt of an interview that explains a bit of the work SMS has done to address oversteer simulation.
     
    Last edited: Feb 9, 2017
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  14. Matej

    Matej Premium

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    Thank you @Wolfe for thoroughly answering this, it explains everything. :tup:
     
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  15. Wolfe

    Wolfe Premium

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    On the same subject but regarding PCARS2, here's something from the Q&A going on now:
    With PCARS1 as a starting point, if oversteer is more controllable -- especially snap oversteer, which is welcome but harsh as it is now -- and scrubs speed more accurately to allow for full-length drifts, I see no reason to believe PCARS2 will be anything less than very satisfying to drive. I say that with the tempered expectation that it won't definitively steal the #1 crown in handling dynamics...but it should be a lot of fun. :)
     
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  16. IanBell

    IanBell Premium

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    It will.
     
  17. Wolfe

    Wolfe Premium

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    It will be a lot of fun, or it will be #1 as well? :p

    No disrespect intended; after twelve years of sims with roadcar handling dynamics that have never quite measured up to Enthusia Professional Racing or Live for Speed by my estimation, it has been too long since a new sim raised the bar. It's fortunate that you're in a position to avoid getting slaughtered by the press for the game being "too hard" like EPR, and your team works at light speed compared to the humble LFS team.
     
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  18. super_gt

    super_gt

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    And Live For Speed will most likely get new tyre physics this year which will make it even better.

    Hello @IanBell
    Another problem with Project CARS 1 is that the cars have too much grip on the grass,here is an example:
    Will it be corrected in Project CARS 2?
     
    Last edited: Feb 10, 2017
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  19. Rotorist

    Rotorist

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    I am on the trial of the Pagani version on steam which is free and recently got the full game (not the dlc) but during the trial, I can see that snap oversteer and a tendency of sudden movement of the cars in the Pagani version seem to be the plaque that make the game tough to get into it and invest time and effort to learn the cars and the physics better. Any suggestions from the more experienced fellows of GTP forum?
     
  20. Speedster911

    Speedster911

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    I've actually seen a vid of some Euro guy on YT running a comparison between AC and CARS; he pointed out as well how the cars remain stable stepping into grass or getting one of the tires off-track.
     
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