When a wheel is broken (BUG)

[alanrotoi]

I called a bug like this. It's hard to explain but it happened a lot with INDY. After a jump or several jumps in power gear suddenly the car turns by itself to a side and you have to force it to the opposite way just to maintain the direction. Sometimes it fixes after a jump or a savage turn but sometimes not. Did it happened to you?

Also if you use F3 view you can see the front wheels in a different position than the normal (you can see the axis between the wheels over the car).

Stunts has only two states of the car: fine or crashed. There aren't broken parts of the car like other games of those times (i.e. Test Drive 2 you can broke some shifting and keep driving without it). Would be this bug a discarded attempt of introduce a complex broken car status? Or just a bug? I'm sure I had few replays in zaks with that bug but I can't remember witch.

[dreadnaut]

Oh yes, I've had the "my Indy drifts to one side" problem before. I usually rewind the replay, because I'm afraid it might make my replay non-replayable. But also because it's very difficult to go anywhere with a broken wheel

[Duplode]

Yup, I have seen this one a few times. It tends to happen upon landing from very aggressive air slides. One example from my ZakStunts replays is Z170 (that's a Jaguar lap, by the way, so it doesn't happen only with powergear cars).

[Cas]

Oh!  This is very interesting and hasn't happened to me or at least, I don't remember. I'd like to see if I can reproduce it. My guess is that it's just a bug, but the amazing thing is that Stunts has so many properties that can change during gameplay. It looks simple, but it is not. Just looking at how many things can be tweaked in car RES files gives you an idea, so I figure some variable related to one or more of these properties could reach a value that it wasn't expected to reach and then you're locked at the other end. I'll try to find that replay

[Ryoma]

I have got it when I push an opponent.

[Cas]

Well, one thing I do remember that I did on purpose many times was as follows:
- First, have the opponent crash his/her car
- Then, approach slowly until you make contact with the crashed car. Too quick and you'll crash too
- Once you make contact, there is a chance you'll crash anyway, but more often, you won't
- You'll get stuck and won't be able to move out. Continue to try moving to the sides while accelerating gently
- If you accelerate too much, you'll eventually crash. If you do everything well, you may still crash
- But, after a while, if you're lucky, your car is suddenly launched flying for no reason either making spirals or shooting high up into the sky!

[alanrotoi]

By the way... It happens that this "drift to one side" alwsys is a turn to the left. Maybe it is linked somehow with our turn left/right problem in other topic.

[CYBERYOGI -CO-Windler]

The "broken wheel syndrome" is likely not a bug at all but a feature intended as an implicit time penalty for skidding too far offroad at high velocity.

That is to say, the arcade versions of "Hard Drivin" and "Race Drivin" do the same! (I wrote much about them here.) When e.g. landing after a jump and drifting off the track, the car keeps spinning like mad and can not be properly steered unless you brake it to complete halt. I had thought this was a MAME emulation bug, because the arcade hardware has sophisticated force feedback steering with a 2nd rotation sensor behind a spring to detect the steering wheel torque separate from rotation angle. But to my surprise "Stunts" does it too, so the programmers likely just copied the behaviour from those arcade machines (no matter if this was physically realistic).

The only difference is that "Race Drivin" behaves more complex, i.e. when e.g. on the "Super Stunt Track" landing after the bigger (right) ramp without perfectly centered steering wheel(??), the car skids offroad and will vigorously rotate first in one direction and then in the other until it has come to almost complete halt, bouncing around like dancing on its 4 wheels. Possibly this attempts to simulate that first only the (still spinning?) left front wheel has contact with the ground (pulling it to the right), then tips over to the other edge and makes only the right front wheel getting contact and hence changes direction (pulling it to the left) like a tumbler gear. To me (I am neither physics professor nor stunt driver) this seems very unrealistic when driving on grass. The phenomenon is only triggered when skidding far enough off the road (e.g. leaving the map tile of that road segment?). "Stunts" imitates this behaviour in a simpler way, making the car constantly rotate in only one direction (like a stuck turned steering wheel) until the car is fully stopped. So this is no gradual phenomenon but seems to be a state machine that in certain conditions sets it into a special "excessive skidding" state (broken wheel syndrome) that gets only reset when reaching 0MPH.

[Daniel3D]

It could be. The physics mechanics are not fully understood yet.
Like we know that there is a difference in the computing of the left and right steering. But it's difficult to pinpoint that in the code.
If it is a feature, then it's not well defined in the code, and either not fully implemented or badly cut from the game.

[CYBERYOGI -CO-Windler]

I think "Stunts" tries to mimic the behaviour of those arcade games as a penalty for bad driving. That is to say, "Race Drivin" (at least on MAME with mouse control) is much more sensitive to driving mistakes. Its car (the default red one) is like a raw egg that shatters immediately when landing after a jump only slightly too fast, and it goes into "broken wheel" mode already when on grass I turn the steering wheel too far in one direction or rapidly steer alternatingly left and right (like the moose test maneuver) even without driving excessively fast. I first suspected that it simulates something like tyre wear by too much skidding or mud crusted smeary tyres (those need a while to clean themselves) but I doubt that the modelling is that complex.

The cars in "Stunts" are much more forgiving, but many of them are incapable to jump over the drawbridge at all, which here needs much higher velocity. In Hard-/Race Drivin it is something like 60 to max. 80 MPH (faster makes you crash), while Stunts needs 120 or such. (I don't remember exact details.)