Project cars 2 bug report Q&A

  • Thread starter TDZdave
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Drove 2 races today Nordschleife in combination with the GP-circuit.

1st 9 rounds, GTE+GT3+GT4+GroupA. CPUs made one pit stop all the race.

2nd run. 12 rounds else same conditions. Each round, GTE and GT3 cars were in the pit until I exit the game in round 4.

Things I changed from the first to second race:
- 12 instead of 9 rounds
- Aston Martin GTE for Ferrari GTE
- Weather slots (clear to random random....instead clear, clear, clear)

I will do some trys now and I hope I can figure out if the problem occurs in any certain combination to "fix" this by my own in avoding it as far as possible.
 
There's a annoying physics bug on rear mass movement, grip levels on rear tires are going fine until slip angle hits some weird hard coded value which triggers rear movement to accelerate even there's no such force effecting on rear, just magical push from side starts to happen and push more speed on slide and over rotates car body.

Edit: investigated bit more, feels like roll resistance of front wheels are getting unrealistic values comparing mass movement force vector versus rear movement force vector. Like stalling front and adding it inertia to rear moment and going over.

Edit 2: more testing, this starts from simplicity of grip/mass values handled by front wheels, or should I say problem of one wheel handling mass and grip, game physics engine makes always front outer wheel dominant to carry load and grip, meaning at even stand still car and 1° turn on wheel eliminates nearly totally "inside" front wheel, same happens during braking, if your wheel points to one direction it will pretend at most of braking is on "outer" wheel, even it's not outer, only pointing inward.
Now I understand why it felt sometimes like front was single wheeled and car as trike.
But this shouldn't be a hard change on engine, even going under fence and just adding faded values to other side and make sure at dominant wheel is decided from mass travel force versus ground, not just driving wheel.



And please don't even start to try explain at it's normal, I have bad habit on winter times to spin E class merc on 10m x 10m spot and doing donuts and 8-figures inside that area for 30 mins on row without stopping spin even a second, surface is plain ice covered with snow and car with friction winter tires. So if this kind of super boost sideway acceleration is real I would have encouraged it already.
 
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OdeFinn
There's a annoying physics bug on rear mass movement, grip levels on rear tires are going fine until slip angle hits some weird hard coded value which triggers rear movement to accelerate even there's no such force effecting on rear, just magical push from side starts to happen and push more speed on slide and over rotates car body.

Edit: investigated bit more, feels like roll resistance of front wheels are getting unrealistic values comparing mass movement force vector versus rear movement force vector. Like stalling front and adding it inertia to rear moment and going over.

Edit 2: more testing, this starts from simplicity of grip/mass values handled by front wheels, or should I say problem of one wheel handling mass and grip, game physics engine makes always front outer wheel dominant to carry load and grip, meaning at even stand still car and 1° turn on wheel eliminates nearly totally "inside" front wheel, same happens during braking, if your wheel points to one direction it will pretend at most of braking is on "outer" wheel, even it's not outer, only pointing inward.
Now I understand why it felt sometimes like front was single wheeled and car as trike.
But this shouldn't be a hard change on engine, even going under fence and just adding faded values to other side and make sure at dominant wheel is decided from mass travel force versus ground, not just driving wheel.



And please don't even start to try explain at it's normal, I have bad habit on winter times to spin E class merc on 10m x 10m spot and doing donuts and 8-figures inside that area for 30 mins on row without stopping spin even a second, surface is plain ice covered with snow and car with friction winter tires. So if this kind of super boost sideway acceleration is real I would have encouraged it already.
Click to expand...

So you make a video and don't include the telemetry,brilliant, You actually drive around in circles for 30 minutes with your car,that explains pretty much everything to me.
 
OdeFinn
There's a annoying physics bug on rear mass movement, grip levels on rear tires are going fine until slip angle hits some weird hard coded value which triggers rear movement to accelerate even there's no such force effecting on rear, just magical push from side starts to happen and push more speed on slide and over rotates car body.

Edit: investigated bit more, feels like roll resistance of front wheels are getting unrealistic values comparing mass movement force vector versus rear movement force vector. Like stalling front and adding it inertia to rear moment and going over.

Edit 2: more testing, this starts from simplicity of grip/mass values handled by front wheels, or should I say problem of one wheel handling mass and grip, game physics engine makes always front outer wheel dominant to carry load and grip, meaning at even stand still car and 1° turn on wheel eliminates nearly totally "inside" front wheel, same happens during braking, if your wheel points to one direction it will pretend at most of braking is on "outer" wheel, even it's not outer, only pointing inward.
Now I understand why it felt sometimes like front was single wheeled and car as trike.
But this shouldn't be a hard change on engine, even going under fence and just adding faded values to other side and make sure at dominant wheel is decided from mass travel force versus ground, not just driving wheel.



And please don't even start to try explain at it's normal, I have bad habit on winter times to spin E class merc on 10m x 10m spot and doing donuts and 8-figures inside that area for 30 mins on row without stopping spin even a second, surface is plain ice covered with snow and car with friction winter tires. So if this kind of super boost sideway acceleration is real I would have encouraged it already.
Click to expand...

You are better off posting this on the official forums, they are more “technical”.

It sounds like you know a lot more about software coding than me, but I get the same sensation from the physics. Especially on downshifts into low gears with the rear suddenly stepping out violently at a certain slip angle. Even when driving very slowly, going into 1st gear is usually risky. The car will do a weird rear end half slide like your ice video.

With the front end this is something I’ve recently come across and it’s driving me crazy. It seems no matter what I do the inside front will always lock on combined braking and cornering as soon as I turn the wheel even a tiny amount. Your 3 wheeler description makes since if that’s what’s happening and the game completely unloads the inside at small steering angles.
 
ozwheels
Especially on downshifts into low gears with the rear suddenly stepping out violently at a certain slip angle. Even when driving very slowly, going into 1st gear is usually risky. The car will do a weird rear end half slide like your ice video.
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Basically when you're downshifting mid-corner you're dumping a bunch of torque onto the LSD and causes the system to unlock. So much of this behavior can be cured/reduced via LSD tinkering (try reducing ACCEL lock). Some players like this as it allows for more aggressive exits but some players find that initially it can be too aggressive
 
The_American
Basically when you're downshifting mid-corner you're dumping a bunch of torque onto the LSD and causes the system to unlock. So much of this behavior can be cured/reduced via LSD tinkering (try reducing ACCEL lock). Some players like this as it allows for more aggressive exits but some players find that initially it can be too aggressive
Click to expand...
I’m not following you completely. If the vehicle is slowing down wouldn’t it be decel lock that needs to be increased (smaller ramp angle) or is it the rpm increase from the downshift causing the diff to act on the acceleration side?

What about downshifting in a straight line in a heavy braking zone, let’s say 3rd and 2nd gear at Monza turn 1.
 
killerjimbag
So you make a video and don't include the telemetry,brilliant, You actually drive around in circles for 30 minutes with your car,that explains pretty much everything to me.
Click to expand...
Telemetry, if you mean that HUD choice it was on purpose, due your earlier approach I'm not showing good FFB settings for Logitech wheels in public, but might post telemetry video later if I get some blur on there.

And anyone can test those mentioned and showed in video fails.

IF physics are working THEN it should rise revs when that swing acceleration starts, but no it's not doing it (but again mass doesn't accelerate itself). Plus forces from front aren't directly transferable to rear as current physics engine does, there's body lenght lever between and so on.. But I'm not on SMS payroll to solve this more, they should figure problem from this, probably already knowing it, or there's problem on company inside information transfer.
 
OdeFinn
Telemetry, if you mean that HUD choice it was on purpose, due your earlier approach I'm not showing good FFB settings for Logitech wheels in public, but might post telemetry video later if I get some blur on there.

And anyone can test those mentioned and showed in video fails.

IF physics are working THEN it should rise revs when that swing acceleration starts, but no it's not doing it (but again mass doesn't accelerate itself). Plus forces from front aren't directly transferable to rear as current physics engine does, there's body lenght lever between and so on.. But I'm not on SMS payroll to solve this more, they should figure problem from this, probably already knowing it, or there's problem on company inside information transfer.
Click to expand...
🤬 are you going on about now. Put on the telemetry in your video.It has nothing to do with whatever device your using. If you can prove physics are not working,then please prove it! If not then we have another set of posts that seem to ramble on about nothing that is factual. Having seen this over the years is tiresome to say the least.👎
 
killerjimbag
🤬 are you going on about now. Put on the telemetry in your video.It has nothing to do with whatever device your using. If you can prove physics are not working,then please prove it! If not then we have another set of posts that seem to ramble on about nothing that is factual. Having seen this over the years is tiresome to say the least.👎
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Happy New Year you too!
 
Happy New Year all!!

giphy.gif


:sly:
 
ozwheels
I’m not following you completely. If the vehicle is slowing down wouldn’t it be decel lock that needs to be increased (smaller ramp angle) or is it the rpm increase from the downshift causing the diff to act on the acceleration side?

What about downshifting in a straight line in a heavy braking zone, let’s say 3rd and 2nd gear at Monza turn 1.
Click to expand...
My mistake, you are correct. Increase the decel lock (by lowering the appropriate ramp angle). This should also help with heavy braking straight line stability. I would also reduce brake pressure as the ABS system modeled in the game is a bit too binary
 
The_American
Basically when you're downshifting mid-corner you're dumping a bunch of torque onto the LSD and causes the system to unlock. So much of this behavior can be cured/reduced via LSD tinkering (try reducing ACCEL lock). Some players like this as it allows for more aggressive exits but some players find that initially it can be too aggressive
Click to expand...
I think the differential settings are highly undervalued and misunderstood. The folks that understand how to tune differentials are going to have much better handling vehicles. I was so excited to see this tuning option added to PCars 2. For anyone that's confused on how a differential, or LSD, works, there's a ton of information available with some googling. Real pit crews adjust differentials for every track, and we should too. It's really an amazing addition to the game.
 
Just did an online race, i was in 3rd, the guy in first got disconnected or something, now i'm in 2nd and being told to give back to position to the guy in 3rd who was behind me the whole time. Hoping it would go away i kept going, and got a drive-thru penalty, wtf?
 
StefanMac
Just did an online race, i was in 3rd, the guy in first got disconnected or something, now i'm in 2nd and being told to give back to position to the guy in 3rd who was behind me the whole time. Hoping it would go away i kept going, and got a drive-thru penalty, wtf?
Click to expand...
Yeah that's a known bug. Has happened to me twice in the last couple of months.
 
OdeFinn
There's a annoying physics bug on rear mass movement, grip levels on rear tires are going fine until slip angle hits some weird hard coded value which triggers rear movement to accelerate even there's no such force effecting on rear, just magical push from side starts to happen and push more speed on slide and over rotates car body.

Edit: investigated bit more, feels like roll resistance of front wheels are getting unrealistic values comparing mass movement force vector versus rear movement force vector. Like stalling front and adding it inertia to rear moment and going over.

Edit 2: more testing, this starts from simplicity of grip/mass values handled by front wheels, or should I say problem of one wheel handling mass and grip, game physics engine makes always front outer wheel dominant to carry load and grip, meaning at even stand still car and 1° turn on wheel eliminates nearly totally "inside" front wheel, same happens during braking, if your wheel points to one direction it will pretend at most of braking is on "outer" wheel, even it's not outer, only pointing inward.
Now I understand why it felt sometimes like front was single wheeled and car as trike.
But this shouldn't be a hard change on engine, even going under fence and just adding faded values to other side and make sure at dominant wheel is decided from mass travel force versus ground, not just driving wheel.



And please don't even start to try explain at it's normal, I have bad habit on winter times to spin E class merc on 10m x 10m spot and doing donuts and 8-figures inside that area for 30 mins on row without stopping spin even a second, surface is plain ice covered with snow and car with friction winter tires. So if this kind of super boost sideway acceleration is real I would have encouraged it already.
Click to expand...


That's very intersting finding. Usualy I spin like this when I go off track, cars suddenly start feeling like they're on ice and spinn around their own vertical axis. Check my video below, similar situation, in addition after spinning, physics broke completely, so I could'n continue driving.



It feels like there's some massive weight transfer happening, making car go doing 360's. Or like LOTS of torque on one of the rear wheels spinning lightweight car out, despite it's not necessary lightweight car.
 
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andryush
That's very intersting finding. Usualy I spin like this when I go off track, cars suddenly start feeling like they're on ice and spinn around their own vertical axis. Check my video below, similar situation, in addition after spinning, physics broke completely, so I could'n continue driving.



It feels like there's some massive weight transfer happening, making car go doing 360's. Or like LOTS of torque on one of the rear wheels spinning lightweight car out, despite it's not necessary lightweight car.
Click to expand...

The lack of grip off road is mostly agreed to be wrong. I wouldn’t say that’s a physics flaw.
 
ozwheels
The lack of grip off road is mostly agreed to be wrong. I wouldn’t say that’s a physics flaw.
Click to expand...
Lack of grip in off track situations is not very important, but if you watch my video, you can see really weird behavior with weight transfer, as car is pulled back by some unknown forces connected to forces that made car spin out. It must be physics flaw, because later the physics engine completely freaked out and lifted my car off the ground.

Some cars tend to act similar to this (spinning excessively after loosing traction) on factory "Loose" tuning setups, for example Vantage GT3, AMG GT GT3. I think it has something to do with physics-things user @OdeFinn talked about earlier.

BTW, telemetry HUD is broken in PS4 version, it doesn't show tire load circles when player is controlling the car. (when ai drives out of pit lane for example, tire load circles are normally displayed, then when player takes control over the vehicle, they disappear)
 
The fix I care the most about right now is the weather desync issue for players in the same server regardless it's p2p or dedicated, because yes, happens on normal p2p lobbies as well.

We have best weather system ever seen in a racing game, but it's completely useless to be enjoyed with others online..., wtf

This is without doubt priority fix number1, and I'm starting to worry whether or not they will be able to fix it in any of forthcoming patches.
 
Having two problems at the moment. One is PC2 won't always recognize my T 500 (have to quit and restart the game to fix). Two is if I'm running say a 5 lap race I am disqualified after crossing the finish line after lap 4. Very frustrating because you don't know it will happen until it happens. Anybody have any ideas? Uninstalled and reinstalled the game to no avail.
 
Is anyone else experiences game freezes after exiting Time Trial on PS4? Every time I end it game is not responding and only way I can continue is to shut down game completely and run it again. It is completely game breaking because I don't have my times saved, and launching game on PS4 is very time consuming.
 
AI needs work
Pan European Championship
Sakkito national
Car Nissan Skyline r32
24 or 27 Laps

My position was 7 at 6 laps to the end
The AI is behind the last and does not try to overtake , allowing me to quickly approach the first place.
They all behind AI as a convoy and I use to overcome them all
It should not be like this because the first one should pass the last one and not walk about six laps behind him
 
VetteZR1
Having two problems at the moment. One is PC2 won't always recognize my T 500 (have to quit and restart the game to fix). Two is if I'm running say a 5 lap race I am disqualified after crossing the finish line after lap 4. Very frustrating because you don't know it will happen until it happens. Anybody have any ideas? Uninstalled and reinstalled the game to no avail.
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Online? If so it could me missing a mandatory pitstop.
 
Was watching replay, when changing too different cars, rewinding a little. Sometimes comes up with a fault message and closes the game. Having to start game again, I'm on PS4, anyone had this?
 
diesel97
Any game will do this if you push 20 buttons in 10 seconds. Slow down and give it time to process
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Where was it mentioned he pushed 20 buttons in 10 secs and also why do you think this would be a problem.....I just typed this in about 4 seconds.
 

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