The Stupidity of GT7 physics

  • Thread starter Tuono_GT
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Still no change... Race C earlier, the back end starts sliding and quicker than you can shake a stick I'm into the barrier with the nose of the car and no hope of extracting any time soon. Quite ridiculous PD!
If the back-end was stepping out why are you nose into the barrier?
 
If anyone wants to witness crazy crash physics drive the rotary swapped Capuccino at the 600pp race at Tokyo. After almost 10,000 miles in wet to drying conditions I have had exactly 1 spin where I didn't end up backwards (the only assist I use is abs). The drivetrain also seems to have a lot of rotating weight causing massive heavy flywheel effects, if you start to spin the tires it takes quite a long time for them to stop spinning after releasing the accelerator.
 
I'll try to remember to save the race and post.
You don't need to - the console records everything it sees; you just have to tell it what, of the last 59 minutes and 59 seconds, you want to save.
Now have a short clip from a screen recording but can't seem to upload the file. And can't find info on does/don'ts for uploading :confused:
To where are you trying to upload it?
 
you’re right, the physics of how a car reacts when hitting a barrier at a considerable angle (moreso than simple wall riding) is insanely unrealistic and almost always ends with the car perpendicular to the barrier, or facing backwards, counter to all known laws of physics. This is not how a real vehicle would react — it’s clearly hard-coded behavior, probably to prevent bouncing off of corners to gain an advantage, which was very possible in ancient iterations of the game.
I think video is needed to really assess the problem, but from this post the impact physics don't sound terribly wrong.

1677594413491.png


In this diagram you can see a car impacting a wall. The top image is pre impact. The bottom shows when the car hits the wall. The wall will deform and push back on the car. The total force is the blue arrow. The force components are orange. I've also marked the approximate center of gravity of the car. The vertical force component is very clearly trying to spin the car such that it goes backwards. Depending on the size of each component, which depends on the angle of impact, a spin seems reasonable.
 
I think video is needed to really assess the problem, but from this post the impact physics don't sound terribly wrong.

View attachment 1235309

In this diagram you can see a car impacting a wall. The top image is pre impact. The bottom shows when the car hits the wall. The wall will deform and push back on the car. The total force is the blue arrow. The force components are orange. I've also marked the approximate center of gravity of the car. The vertical force component is very clearly trying to spin the car such that it goes backwards. Depending on the size of each component, which depends on the angle of impact, a spin seems reasonable.
Nothing gets deformed in GT but looking at your diagram and the 45 degree angle, it still makes sense for the car to spin with how unyielding everything is.

The barriers do act weird sometimes, though. Often quite hooky with frontal collisions and as fastone said above, add a bit of wheel spin when you're facing one and you'll be facing backwards in no time at all.
 
Running off track and heading for the barrier just fills me with dread every time and to be frank, because it is so damned annoying and exceedingly frustrating that generally I just quit rather than waste time trying to get back on track, which in most cases is just a futile exercise. Approaching a barrier at an angle, in normal circumstances (and I have experience of this) will result in a deflection of certain degrees that will still enable one to travel forward in the racing direction, all be it slowly and with damage of sorts..
First of all, I agree with you.

I think they do it to penalize idiots but it's also penalizing those of us trying to race properly but make an honest mistake. Instead of figuring out how to improve the SR system, I assume it takes less effort for them to penalize poor behavior in this way.

The problem is, the people who are ruining the game in this manner don't care. They play with all the assists on, thus making it easier to terrorize the rest of us. So, they're operating without penalty and we're forced to suffer with inferior gameplay mechanics (if my assumption is true).
 
Nothing gets deformed in GT but looking at your diagram and the 45 degree angle, it still makes sense for the car to spin with how unyielding everything is.
The deformation doesn't have to be visible, it can be baked into the physics. I'd assume this is the case because modeling deformable barriers would take resources from the rest of the game and PD has historically been hesitant to even model damage to cars.

The truth is, contact forces pretty much only exist due to deformation in the real world, even if you can't see it. So any kind of collision modeling is accounting for deformation in the math in some way or another. It's just a matter of how sophisticated the modeling is.

In GT the wall likely pushes back according to the impact angle, so the situation would be the same as my image except that the wall doesn't bend at the impact point. The resulting forces would be the same and the car would spin with the right components, as you said.
The barriers do act weird sometimes, though. Often quite hooky with frontal collisions and as fastone said above, add a bit of wheel spin when you're facing one and you'll be facing backwards in no time at all.
I haven't played GT7 but I've seen similar things in older GT games. The kind of event I'm envision looks more like a bug or physics engine quirk. I'd be curious to see if it still happens in the latest games.
 
You don't need to - the console records everything it sees; you just have to tell it what, of the last 59 minutes and 59 seconds, you want to save.

To where are you trying to upload it?
Here in the thread...
 
you’re right, the physics of how a car reacts when hitting a barrier at a considerable angle (moreso than simple wall riding) is insanely unrealistic and almost always ends with the car perpendicular to the barrier, or facing backwards, counter to all known laws of physics. This is not how a real vehicle would react — it’s clearly hard-coded behavior, probably to prevent bouncing off of corners to gain an advantage, which was very possible in ancient iterations of the game.

On the one hand, if it were a real race, your car would be too damaged to continue the race (and in some cases totally obliterated), so no matter what the game does, it’s going to seem fake, since implementing a realistic damage model is apparently totally off the table.

Besides, ending the race there isn’t an outcome gamers would desire. So they’ve got to do something that punishes the driver, but still allows them to proceed. Someone somewhere decided a hard-coded “crash” that points your car the wrong way was a more immersive option than for example forcing you to drive 50mph for five seconds like in GT4. Terrible decision, in my opinion. The hard-coded crash is far more frustrating and unfair.

Related gripe: there should be a visual countdown on screen before the game resets your vehicle! Often I’m turning the wheel to try to get back on track, when the game suddenly and without warning plops me back on a straightaway at speed, which of course sends me crashing into the barrier since I had the wheel turned. Idiotic design.
Yeah so annoying when It puts you back on track without notice and u drive right back off its like F#$%
 
I don’t even know where to start when it comes to complaining about this game.

Penalty system:
PD have never been able to get this right. But lately it’s the worse I’ve ever seen. Nothing is more annoying then getting pushed into a barrier and then you getting the 1.5s penalty for colliding with such barrier. Even worse when the collision is intentional and the perpetrator gets away with no penalty what so ever. Bloody joke.

Physics:
I laugh watching time trial attacks and seeing guys downshift from 6th to 1st in an instant then to jump back up to 3rd or 4th as to not spin the tires under acceleration. This just doesn’t happen in real life.

Online:
Multiplayer is still in Undriveable with lag and stuttering.

Updates:
Dribs and drapes approach is getting old along with Kaz silhouettes.

Lately I find after one race I end up quiting from annoyance. Gladly I look for forward to buying a pc and never touching this game again.
 
I don’t even know where to start when it comes to complaining about this game.

Penalty system:
PD have never been able to get this right. But lately it’s the worse I’ve ever seen. Nothing is more annoying then getting pushed into a barrier and then you getting the 1.5s penalty for colliding with such barrier. Even worse when the collision is intentional and the perpetrator gets away with no penalty what so ever. Bloody joke.

Physics:
I laugh watching time trial attacks and seeing guys downshift from 6th to 1st in an instant then to jump back up to 3rd or 4th as to not spin the tires under acceleration. This just doesn’t happen in real life.

Online:
Multiplayer is still in Undriveable with lag and stuttering.

Updates:
Dribs and drapes approach is getting old along with Kaz silhouettes.

Lately I find after one race I end up quiting from annoyance. Gladly I look for forward to buying a pc and never touching this game again.
Thank you for announcing that you will be leaving in an irrelevant thread, see you never.
 
If anyone wants to witness crazy crash physics drive the rotary swapped Capuccino at the 600pp race at Tokyo. After almost 10,000 miles in wet to drying conditions I have had exactly 1 spin where I didn't end up backwards (the only assist I use is abs). The drivetrain also seems to have a lot of rotating weight causing massive heavy flywheel effects, if you start to spin the tires it takes quite a long time for them to stop spinning after releasing the accelerator.
They need to give us a working clutch and not require us to buy the stick shift. Tires spin, push clutch in, done! No more power to wheels. Save the slide. Just like driving in winter, you begin to feel it sliding, youcan let off the throttle completely but you’re better off to push the clutch in and gather it up. In fact sometimes in my truck (automatic) if I’m slipping coming to a stop I throw it in neutral, night and day difference in ability to stop when you totally remove power to the wheels.
 
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