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I know perfectly well that the development of the game is somewhat stalled (a pity, because I love the game), but I would like to include a game option that varies the physics to make them a little more real. I know that the game is called V-Drift, and that consists as its name says (among other things) in drifting, but it would be nice to choose between a Drift mode and a simulation mode. In simulation mode cars could enter a little faster into curves without drift.

What's your opinion?
Despite being called VDrift there is no special drift code in the game.

From my Vdrift coding and experiments realism is a complicated topic.

1. Is the model itself realistic?
To me this starts with the tires (the only thing that keeps you on the road), followed by
suspension, driveline and rigid body dynamics.
VDrift is using a quasi-static tire model. This means tire parameters have been recorded at a certain fixed velocity (like 50km/h) for a range of loads and slip (angles). We essentially assume that they remain the same, which technically is not correct. I've implemented a "physical" tire model that tries to do a bit more, just to understand tire behavior a bit better. It is still a quay-static model, but it has a velocity dependency and uses physical parameters. It is something that could be enabled. But I am not sure how it would affect the AI. Haven't really had the motivation to find out, lol.
I've recently worked on the suspension. Trying to get camber changing with wheel travel depending on suspension geometry. VDrift is still applying tire forces at the wheel axis. This is also something I'd love to address. I've got some ideas, not sure how well they'll work out though.
There are a number of other things that are not particularly realistic. The engine is a simple static torque map for example. I believe tires and suspension have the most effect on realism though.

2. Are the model parameters realistic?
A realistic model is not worth much if your tire, suspension, driveline, canter of mass, inertia parameters etc are not realistic.

3. How do you translate player inputs to make it feel realistic?
Image someone tried to control a real car using a keyboard or gamepad at high speeds. That would not end well.
One particular issue I struggle with in VDrift is steering. When you drive a real car you seldom use the whole steering range, mostly just when parking. In VDrift you'll tend to steer too much which feels weird. I've added a "Steering assist" to limit that, but it is more a band aid than anything else.

p.s.
You know what would be awesome? If we could somehow get some really detailed telemetry and parameters from a real car. All of the inputs, the state of each wheel, engine, velocities etc, just as much data as possible, to see if I can be replicated in VDrift.
(04-11-2019, 12:33 PM)NaN Wrote: [ -> ]Despite being called VDrift there is no special drift code in the game.

From my Vdrift coding and experiments realism is a complicated topic.

1. Is the model itself realistic?
To me this starts with the tires (the only thing that keeps you on the road), followed by
suspension, driveline and rigid body dynamics.
VDrift is using a quasi-static tire model. This means tire parameters have been recorded at a certain fixed velocity (like 50km/h) for a range of loads and slip (angles). We essentially assume that they remain the same, which technically is not correct. I've implemented a "physical" tire model that tries to do a bit more, just to understand tire behavior a bit better. It is still a quay-static model, but it has a velocity dependency and uses physical parameters. It is something that could be enabled. But I am not sure how it would affect the AI. Haven't really had the motivation to find out, lol.
I've recently worked on the suspension. Trying to get camber changing with wheel travel depending on suspension geometry. VDrift is still applying tire forces at the wheel axis. This is also something I'd love to address. I've got some ideas, not sure how well they'll work out though.
There are a number of other things that are not particularly realistic. The engine is a simple static torque map for example. I believe tires and suspension have the most effect on realism though.

2. Are the model parameters realistic?
A realistic model is not worth much if your tire, suspension, driveline, canter of mass, inertia parameters etc are not realistic.

3. How do you translate player inputs to make it feel realistic?
Image someone tried to control a real car using a keyboard or gamepad at high speeds. That would not end well.
One particular issue I struggle with in VDrift is steering. When you drive a real car you seldom use the whole steering range, mostly just when parking. In VDrift you'll tend to steer too much which feels weird. I've added a "Steering assist" to limit that, but it is more a band aid than anything else.

p.s.
You know what would be awesome? If we could somehow get some really detailed telemetry and parameters from a real car. All of the inputs, the state of each wheel, engine, velocities etc, just as much data as possible, to see if I can be replicated in VDrift.

This talk is too technical for me. I am a simple gamer. Although, more or less, I understand what you're talking about, I have no idea how it could be implemented. But from your words I deduce that it is something tremendously complicated, so I appreciate all your efforts.
As I said, what I mean in a simple way is that I notice that I have to enter the curves much more slowly than in other games because the car is very simple to skid. Yesterday, for example, I was trying to drive the Ferrari Miura and it was practically impossible, even using a steering wheel. About what you say about the range of the steering wheel, in Linux I lower it from 900 (by default) to about half. For that I use the Oversteer application created by a member of our community, you can found it on  https://github.com/berarma/oversteer . About physics perhaps you could see how they do in Speed Dreams (https://sourceforge.net/p/speed-dreams/wiki/Home/), another Open Source driving game.

Cheers!
I've gone through the SV parameters (SV.car file): implemented double wishbone suspension, balanced weight to 44/56%, stiffened front suspension, reduced brake pressure a bit.

Front rear grip balance should be good now. Brake balance is not there yet I think.

It is super easy to lose the tail if you are not careful with the throttle/brakes (at least when driving with keyboard). I'll give it a try with the steering wheel/pedals and see if I can improve the handling a bit more.
(04-13-2019, 09:07 AM)NaN Wrote: [ -> ]I've gone through the SV parameters (SV.car file): implemented double wishbone suspension, balanced weight to 44/56%, stiffened front suspension, reduced brake pressure a bit.

Front rear grip balance should be good now. Brake balance is not there yet I think.

It is super easy to lose the tail if you are not careful with the throttle/brakes (at least when driving with keyboard). I'll give it a try with the steering wheel/pedals and see if I can improve the handling a bit more.

Thanks a lot!

I see you updated the .car file ( https://sourceforge.net/p/vdrift/code/1425/ ) and now the Miura is a little bit more stable when you press the brakes.
I was playing today with Ferrari F40 and with this car I feel a more realistic reactions in car. When you press the brake softly, the rear of the car does not lose control so easily. I also try Ferrari 360 Modena (360 in game) , and is very, very difficult to control  when you press brake. With Ferrari Enzo (EF in game) ,the previous effect is not so pronounced, in addition the car takes a lot of time to brake. I recorded a video where you can see the reactions of the F40 in Monza:




From my ignorant point of view (I'm just a player), I think this kind of car reactions should be checked. It is true that there are cars that are much more unstable and difficult to drive than others, but I think that in some cases they are too exaggerated (like Lamborghini Miura SV).  A good starting point can be the Ferrari F40
It's true that the instability of some designs feels a little bit exaggerated, nothing terrible, but it still feels over the top. Or is it justified? Because, after all, the most powerful car I've ever driven has something like the fourth of the horsepower of the game's ones, so I may just have never experienced that IRL.
Driving the same models in another car simulators it's more easy. I think that the cars needs more grip