Jump to content
DIRT 5 - Chat about the game and get support here. Read more... ×
Christmas Period - Codemasters Staff and Support Read more... ×

Archived

This topic is now archived and is closed to further replies.

[DiRT 4] Constructive feedback on the subject of car-feel and physics: The Ultimate Thread

Recommended Posts

Slowish said:
Dirt-handling issues aside for a moment, the tarmac handling is where the physics really don't hold up when compared to Road-racing Sim's; those titles just feel far more precise and detailed in their behavior and far more informative regarding FFB self-aligning torque, threshold of grip, buildup of steering resistance prior to grip-loss, torque-steer, etc. Some of those can be very subtle effects but, can be amplified when using a direct-drive wheel so their presence (or lack of) becomes far more obvious to the player.

Still, I'm not as bothered by the tarmac handling because I play Dirt titles primarily for the Dirt-racing aspect but, of course - it would be great to have things working at a high level across all modes - especially in career mode. Those same subtleties I mentioned above are also absent from RallyX tarmac but, I should mix in more of the game FFB to better understand how the FFB algorithm may affect the tarmac feel overall.

None the less, the game FFB and telemetry-based FFB should not differ by that much regarding those effects felt through the wheel - unless, they involve "canned" FFB effects, not those derived directly from the game physics.  I'm not saying that is the case here but, it's something that I want to test further to find the right formula for tarmac because, it doesn't feel great as it is now.
RIGHT ON!

Share this post


Link to post
Share on other sites
i would love Codies to come out and tell us what they do different from Racerroom ,AC , Automobilista etc? Whats the big secrecy if its calculated,lets hear about it 

Share this post


Link to post
Share on other sites
battfinkz said:
Fab, ive said all long i believe it ro be some sort of assists bug or aid that's glitched. The actual  physics feel fantastic, i dont believe for one second it has anything to do with them.
@battfinkz Believe me, we're on the same page here (literally :D). But how can you be certain about the physics, when there actually are assists on, that interfere with the handling like you said ;)?

Share this post


Link to post
Share on other sites
Because that's what assists do. If they restrict difficulty by increasing grip, or reducing power (traction control) then they are interfering with the grip levels or physics engine. When your flat out in this game with all assists off in fearless its an absolute blast, but certain cars on certain tracks ate definitely off, just cant quite put my finger on what the issue is stemming from

Share this post


Link to post
Share on other sites
battfinkz said:
Because that's what assists do. If they restrict difficulty by increasing grip, or reducing power (traction control) then they are interfering with the grip levels or physics engine. When your flat out in this game with all assists off in fearless its an absolute blast, but certain cars on certain tracks ate definitely off, just cant quite put my finger on what the issue is stemming from
I agree that there are some oddities that seem to affect certain car / stage combinations in one session and then, may be difficult or impossible to reproduce in another; just as it is for us, it may be the case for developers. This is one aspect that I suspect may pertain to aids / assist's somehow being applied when they shouldn't be but, I haven't been able to reproduce it consistently either.

Share this post


Link to post
Share on other sites
@battfinkz But a low moment of inertia may cause the same things (being affected by seemingly more grip). I'm not saying you're wrong, but you can't say it isn't the weight distribution without giving any evidence to proof it wrong. Besides, this only comes into play when you rotate the car. Under full throttle or braking in a straight line, apart from some lessened pitch angle, it wouldn't change much, because the absolute weight and the COG stays the same.

Share this post


Link to post
Share on other sites
Slowish said:
Dirt-handling issues aside for a moment, the tarmac handling is where the physics really don't hold up when compared to Road-racing Sim's; those titles just feel far more precise and detailed in their behavior and far more informative regarding FFB self-aligning torque, threshold of grip, buildup of steering resistance prior to grip-loss, torque-steer, etc. Some of those can be very subtle effects but, can be amplified when using a direct-drive wheel so their presence (or lack of) becomes far more obvious to the player.

Still, I'm not as bothered by the tarmac handling because I play Dirt titles primarily for the Dirt-racing aspect but, of course - it would be great to have things working at a high level across all modes - especially in career mode. Those same subtleties I mentioned above are also absent from RallyX tarmac but, I should mix in more of the game FFB to better understand how the FFB algorithm may affect the tarmac feel overall.

None the less, the game FFB and telemetry-based FFB should not differ by that much regarding those effects felt through the wheel - unless, they involve "canned" FFB effects, not those derived directly from the game physics.  I'm not saying that is the case here but, it's something that I want to test further to find the right formula for tarmac because, it doesn't feel great as it is now.
Since they have to simulate multiple surfaces I fully undestand if the tarmac won't be as refined as in the tarmac only sims.

Share this post


Link to post
Share on other sites
I wouldnt say it was a fundamental issue with parameters affecting inertia either FAB, as some cars feel perfectly fine on all surfaces. Also, im yet to experience a car feel 'wrong' under braking? Some cars in d4 have some mind boggling default setups, why i dont know but a little tinkering fixes any braking issues i had with certain cars. Fully agree it seems to be worse under throttle though, and i have even noticed throttle drop off at times? Surely that points to some sort of traction control glitch?

Personally, again i believe its an aid of some sort, as when i mean a car feels wrong, i mean it snaps back to grip incorrectly, and what should be opposite lock when powering out of a slide can intact be turning in lock with rear bias torque, and even some rwd cars. 

I dont believe its a grip issue as i can get passed the lateral grip levels with ease to initiate a slide (not that you would deliberately do that), but its almost as if the game controls this when it detects you're doing it. Very weird

I think the best way i could demonstrate what im trying to get across is by finding a michigan track with a massive straight and hairpin at the end, i can be bombing it at 100mph plus, see the hairpin, start braking, initiate a scandanavian flick, lock the front up just for a second, swing the front end into the corner, feel the back fly around, and have one seriously massive smile on my mug as it feels superb, then, as i power out of the corner sideways, im turning into the bend, when i should be at oppisite lock, and the smile turns to a major pout  :D :/  lol.

All of this, too me, tells me that the physics, grip levels and inertia are spot on, but then some stupid assist/aid glitch ruins my fun. Cant explain it but im not giving up on my 'research'. Lol

Share this post


Link to post
Share on other sites
The things you described @battfinkz, are exactly the same experiences I got. So from my point of view this could well be an aid or assist issue or it's some parameters of the cars, including that rotational inertia thing I described. Until we get any data or info on this or somebody has an idea or way to disproof this, this will just be another theory. But still, I believe all ideas are welcome if they help ruling things out ;).

EDIT: It is still possible that cars can have a fitting moment of inertia, if the car is build very balanced. Thats what I think is the reason this doesn't affect modern cars that much, or other specific cars. So think of it like a setup-parameter depending on the car, because every car has a different weight distribution.

Share this post


Link to post
Share on other sites
Not sure man. The reason im shying away from the claim its inertia is because i have been reading comments in this post for a while now and certain tests and discussions point to something else.

About a week ago people were discussing the 2001 impreza and how difficult (well, impossible) it is to initiate a doughnut in the car, try it in dirtfish. This doesnt point to an inertia issue imo, to me its some sort of traction aid, or weird diff glitch?

I dont know, i just hope they fix it without changing the core engine, that will most likely not happen anyway as they would have to rework the whole core mechanics and that would take a rediculous amount of time 

Share this post


Link to post
Share on other sites
fab1701 said:
The things you described @battfinkz, are exactly the same experiences I got. So from my point of view this could well be an aid or assist issue or it's some parameters of the cars, including that rotational inertia thing I described. Until we get any data or info on this or somebody has an idea or way to disproof this, this will just be another theory. But still, I believe all ideas are welcome if they help ruling things out ;).

EDIT: It is still possible that cars can have a fitting moment of inertia, if the car is build very balanced. Thats what I think is the reason this doesn't affect modern cars that much, or other specific cars. So think of it like a setup-parameter depending on the car, because every car has a different weight distribution.
We already had one user posting great video showing ingame telemetry. Take a look at brake distances. The same user posted a G meter results that cars go through in D4. Not realistic at all.

Share this post


Link to post
Share on other sites
Rotational inertia doesn't really affect braking (except for a minor change in pitch angle), but longitudinal inertia does. I Didn't talked about that, but sure, maybe there is something else going on.

Btw. I got that subaru impreza to doughnut recently, but you have to make some seriously awkward setup changes: Make all of the front suspension settings as soft as possible, including roll bar and all of the rear suspension settings as firm as possible, including roll bar. Lower the front to min and highten the rear to max. Then lower the front dampening values to minimum and set the rear dampening values to max. Without any other setup changes, the Impreza 2001 will doughnut ;). But it doesn't make any sense that way imho. EDIT: sure that hints to some traction issues, but doesn't invalidate inertia.
EDIT2: Now that I think about it, maybe some weight shifted to the rear would actually help with the impreza, as it helps with oversteer to keep the rear going and loose traction easier. But then again, some weight needs to be shifted appropriately to the front to keep the COG balanced. Of course only if this is realistic and equals the imprezas real characteristics.

Share this post


Link to post
Share on other sites
bogani said:
Since they have to simulate multiple surfaces I fully undestand if the tarmac won't be as refined as in the tarmac only sims.
To some extent perhaps but, aside from loose material instability, the underlying physics should not be that different either. Consider what Reiza did with their RallyX cars using an outdated P-motor (ISI) that was not intended for loose surfaces at all.  There are also RX mods for Assetto Corsa that work pretty well considering mod'ers not having access to the underlying code.

PCars2 is reaching into such territory as well and it will be interesting to see how that plays out. iRacing is also adding RallyX later this year IIRC, and they already have the Dirt ovals working so it's completely doable for CM - not easy though.

Share this post


Link to post
Share on other sites
This game is frustratingly inconsistent. I took the Fiesta R5 to the daily Australian stage that had the atrocious Evo VI, and I've found a really great setup for it. Driving this stage with the R5 just feels great. The car moves around pretty much exactly like I want it to. If the lateral/longitudal grip was much less it would feel pretty bad.

Btw, this was the BEST Australian stage I've driven so far. Not much repeating of tiles. It was really great.

https://youtu.be/DGPcYCfZFlU

Share this post


Link to post
Share on other sites
SamRWD. did he use abs for the braking distance test?. If not, how did he regulate maximum braking force without locking the wheels up? Or did he just 100% brake?

Share this post


Link to post
Share on other sites
battfinkz said:
SamRWD. did he use abs for the braking distance test?. If not, how did he regulate maximum braking force without locking the wheels up? Or did he just 100% brake?
AFAIK sim, all assists off. you can make that test yourself (I did many pages back, I even posted a video here somewhere). He tested on a gamepad and wheel. No need to worry about locking the wheels- it is not this kind of game apparently:

https://youtu.be/pCW6WVLY1uw

https://www.youtube.com/watch?v=V3dV4CuR04g

bogani said:
This game is frustratingly inconsistent. I took the Fiesta R5 to the daily Australian stage that had the atrocious Evo VI, and I've found a really great setup for it. Driving this stage with the R5 just feels great. The car moves around pretty much exactly like I want it to. If the lateral/longitudal grip was much less it would feel pretty bad.

Btw, this was the BEST Australian stage I've driven so far. Not much repeating of tiles. It was really great.

https://youtu.be/DGPcYCfZFlU
Would you mind sharing your Fiesta R5 setup? I gave up on that car because I couldn't make it drive the way I like.

Share this post


Link to post
Share on other sites
SamRWD said:
fab1701 said:
The things you described @battfinkz, are exactly the same experiences I got. So from my point of view this could well be an aid or assist issue or it's some parameters of the cars, including that rotational inertia thing I described. Until we get any data or info on this or somebody has an idea or way to disproof this, this will just be another theory. But still, I believe all ideas are welcome if they help ruling things out ;).

EDIT: It is still possible that cars can have a fitting moment of inertia, if the car is build very balanced. Thats what I think is the reason this doesn't affect modern cars that much, or other specific cars. So think of it like a setup-parameter depending on the car, because every car has a different weight distribution.
We already had one user posting great video showing ingame telemetry. Take a look at brake distances. The same user posted a G meter results that cars go through in D4. Not realistic at all.
You mean the user who doesn't understand physics and car dynamics and who posted videos showing realistic g forces in the game, both lateral and longitudinal?

Is this the same user who said that it was impossible for a car to exceed 1g on any surface without serious downforce and who was replied to with a video of an old Audi Quattro pulling 2.5 g on gravel into a square left?

Is this the same user who posted videos of cars with g metres to prove that no car can exceed 1g and yet his videos clearly showed the cars peaking at 1.5 g?

My question is this: When are you guys going to stop describing realistic car behaviours and showing videos showing realistic car behaviour and telling each other that the behaviour is somehow wrong? I mean really, you've been told many times why certain behaviours happen, you've been proven wrong on multiple occasions by actual footage and telemetry data, and yet you persist in your fault finding quest. It really is getting to a point where you're posting the same unsubstantiated nonsense again and again ad nauseum, which is borderline spam. 

At this point it is pretty clear that many of you did not come here seeking after the truth. You've come come here seeking confirmation for your erroneous and unsusbstantiated feelings and opinions.


Share this post


Link to post
Share on other sites
I know for a fact you have to worry about locking the wheels, I've done it too many damn times already.

Share this post


Link to post
Share on other sites
dsiOne said:
I know for a fact you have to worry about locking the wheels, I've done it too many damn times already.
Me too, I've even had to reduce brake force down on some cars to try and prevent it.

Share this post


Link to post
Share on other sites
dsiOne said:
I know for a fact you have to worry about locking the wheels, I've done it too many damn times already.
I don't know, on tarmac I try to avoid locking wheels, but on gravel I usually brake modulating brakes (with a tiny bit of throttle if I need to manage weight transfer). Generally on gravel braking with abs, so not locking wheels at all is not practical. It actually makes braking distance longer.

Anyways I try to enjoy driving this game using real world techniques, even if that makes me slower.

EDIT: I don't know if we undersood each other- braking wheels can be done in D4, but it is not a problem because braking distance with wheels fully locked takes two seconds to stop from 100 kmh to 0. No matter if it's tarmac or gravel.

Share this post


Link to post
Share on other sites
bogani said:
This game is frustratingly inconsistent. I took the Fiesta R5 to the daily Australian stage that had the atrocious Evo VI, and I've found a really great setup for it. Driving this stage with the R5 just feels great. The car moves around pretty much exactly like I want it to. If the lateral/longitudal grip was much less it would feel pretty bad.

Btw, this was the BEST Australian stage I've driven so far. Not much repeating of tiles. It was really great.

https://youtu.be/DGPcYCfZFlU
What setup you use !?default !?

Share this post


Link to post
Share on other sites
dsiOne said:
I know for a fact you have to worry about locking the wheels, I've done it too many damn times already.
It's actually very easy to underrotate and even completely lock up now. ( this is the cause of understeer in many cases) In fact, it's very easy to destabilise the car completely under braking and spin it. It's very easy to oversteer as well. Ive lost  count of  all the times that I had an undriveable car because I overdid the setup slightly towards oversteer and I was just getting monumental snap oversteer resulting in spins with the slightest brake and steering input. 

I really don't understand how some people can say that there is too much grip and how there is a hand of God holding the car. It's as if they're playing a different game to the one I'm playing. 

Share this post


Link to post
Share on other sites
SamRWD said:
dsiOne said:
I know for a fact you have to worry about locking the wheels, I've done it too many damn times already.

EDIT: I don't know if we undersood each other- braking wheels can be done in D4, but it is not a problem because braking distance with wheels fully locked takes two seconds to stop from 100 kmh to 0. No matter if it's tarmac or gravel.

That's not unrealistc. Plus it doesn't take the same on Tarmac and gravel. In fact in the D4 videos with telemetry that were posted by the Hawku0, you can clearly see that it takes longer to stop on Tarmac than it does on the heavy gravel. He's consistently pulling 1.6 g on the heavy gravel and 1.4g on the slippery worn out Tarmac. Plus it takes less time to stop uphill and into compressions, just as you would expect. Doesn't seem particularly unrealistic to me, so once again I don't know what you're whining about.

Share this post


Link to post
Share on other sites
https://youtu.be/qpO5iWg5DB0

E N J O Y. I hope Codemasters will in the future make a true simulator for the simulation fans...

Share this post


Link to post
Share on other sites
Bert637 said:
https://youtu.be/qpO5iWg5DB0

E N J O Y. I hope Codemasters will in the future make a true simulator for the simulation fans...
Did AC finally get a codriver and proper surface division (grass had the same surface properties as the road last time I tried rally stages mods)? Also it shows what quality mods can do to improve a game.

Share this post


Link to post
Share on other sites

×