The online racing simulator
Quote from Niels Heusinkveld :Yes there is an improvement over the previous version. However, over the years LFS has gone from 'some really huge problems' to 'some pretty huge problems'...

You've got to be kidding..... S1 was like.... stupid compared to S2. I wouldn't even compare what S1 was presenting us, because that was almost an entirely different feel. S2 is what we should be focusing on, since it is the focus for the physics. Would be nice if we could just get the S2 Final a solid tire code that feels great, rather than saying it hasn't even improved over S1, that is just absurd. Doesn't let the game evolve at all if you think S1 was somehow better.
Language barrier I suppose I mean it DID get better from s1 to s2 to yesterdays patch. But it was 'far off' and still is 'far off'.. just less far off..
I totally agree with Niels. Its exactly what he sais. Problems are still there in some way, but its harder to see them. Now you have to push harder to get there ...
My LSD'd Polo suffered from lift-off understeer illepall So long as you kept the power on it would pull hard round the corner, but if you suddenly let off it would drift straight on LOL. Then again Mk3 Polo suspension sucks.
Isn't part of the problem that people are actively seeking out and performing tests they know will show the weaknesses of the tire physics? It seems hardly an objective approach.You can find flaws in anything with that mindset.

When that is said, your criticisms may be totally correct, I haven't the first clue about tire physics.But I am not questioning that of course, merely suggesting that preconcieved notions of the physics -or perhaps the game itself- may cause some people to go out of their way to find flaws, and be overly critical (this goes both ways of course).

Would love to see some more threads that focus on both what is good and bad.It would also reduce the risk of people running to the trenches as the discussion gets underway.

Hope someone gets my meaning.

Now please, carry on
#56 - col
Quote from BWX232 :...

It is funny to me to hear people here bash rFactor and call it arcade and whatnot, when some aspects of rF are actually more accurate than LFS.. rF's implementation of the physics engine is not as good, and the FF you get is no where near is good.. but in some ways it is still more accurate. Strange....


A clock that loses 1 second per day only shows the correct time every 236 years - a clock that has stopped completely shows the correct time every day.

col.
Yes true.. Look at the different opinions on current sims. Simracing is very subjective.. some points:

1) Skill level varies a lot: someone doing a 2 minute lap isn't really driving the same as someone who does a 1:55..

2) What is skill? You can learn the limits of the sim but does that mean you're applying real driving skill? Are you stomping on 3 pedals at the same time with overly stiff / oversteery setups that noone would ever use in real life? Even two people who do a 1:55 (lets say thats a near WR time somewhere) will do this in quite different ways. It seems like you drive your 'style' and form an opinion on how the sim reacts to your style...

3) Style is overrated, 95% of simracers suck! (me included!) A LOT of simracers with their opinions have the relative skill level of ending up somewhere mid/backfield in a national celebrity Citroen Saxo race.

4) Computer limitations.. Some points here.. a 'flat' 3D image, some sound.. thats it.. Sims using a different FOV or use more 'head shaking' will make people conclude they 'feel different' even before you get to the physics.

5) Controller limitations. If 95% of simracers are poor (again me included), 98% probably use horrible controls. Standard off the highstreet store shelve pedals are very poor, and my recent trials with a Logitech DFP made me quite sad! Horrible! It made me understand part of the subjective differences. FF settings vary from person to person, totally changing the virtual drivers capability of judging the simulation. Its obvious that FF is flawed with the affordable wheels. Everytime a sim comes out people discuss the FF.. It shouldn't be a point of discussion. A good wheel with a good sim simply 'does' FF, yet the incredibly compromised Logitech designs are causing more grief than giving you feedback. So, sadly, mass produced wheels and pedals are more of a gimmick than good.

High quality pedals are often poor when it comes to brake sensitivity (I ranted about that in AutoSimSport jan/feb issue page 47 if you're interested). Thankfully the high end wheels don't have FF so in that respect they don't add another subjective parameter to the equation.

Then what is happening! We use office chairs and often race in fairly uncomfortable positions, mostly pressing and turning Logitech toys. A squashball makes the brake 'feel nice' (whilst screwing up its sensitivity).. the FF 'is great' while having little relation on the actual steering torque calculated by the sim....

Auch! What can I conclude? We call it simracing but in most cases this is certainly not true looking at the hardware we use. It seems that people look for the immersion and 'thrill'.. This is fine, but hampers your ability to objectively judge something. I can fall for it too! GTR with the canned FF effects and shaking view and sampled sounds has the 'wow' factor. It should however have nothing to do with judging its realism as far as physics go.

7) sims? I think Stefano (Netkar) said that sims are getting more and more alike and that this was a 'good thing' as it showed that basically 'we're getting there'. I disagree. First of all sims are worlds apart, and that is using proper pedals and for the sake of there not being good FF, a non FF smooth wheel. Sims are not all alike, and even if they would be, it might well be that they all would be making the same mistakes..

I always wanted to believe that sims came a 'fair way' since GPL in 1998 but I honestly don't think so. Yes we now have multilink suspensions, brake fade, semi complex aero... but thats no use if the tyre model and/or the data that feeds them is far off. Or if weight transfer is wrong..

Sims aren't good enough yet. Now I can't code more than a multiple choice QuickBasic questionaire so its a stellar achievement that these small programming teams come up with physics and graphics engines at all, but from a pure realism point of view, sims are not truly sims yet.

8)games? I think in 2006 racing sims are not professional and there are few people actually interested in ultimate realism. For some rF does great, for some LFS, for some NKpro, for some N2003. The general maturity of the players shows a lot too.. "I want this car in the game" "I want special drift tyres" "The reversed weight bias Porsche mod is GREAT" etc..

Am I a moaning old man? Well.. yes.. I demand a lot and can't be satisfied when all sims on my harddrive are so different. What if THE real sim showed up tomorrow? I think peoples opinions would still vary a lot because of their poor controls, poor interpretation skills and poor demand for realism.

There is light on the horizon with Todd Wasson's new ideas about tyre modelling, Eero's new sim, and good ol Kaemmer apparantly working on something. I can't wait to try these as its about damn time the bar gets raised! I just hope there are more than 3 people out there who actually care about it.
Quote from RIP2004 :The FWD car on street tyres (GTI) accelerates best when pushing the petal to the metal.

Depends on the tire compound. Some tires lose very little grip when slipping. A bit off topic here, but because of the slipping grip limitations of clutches in most RWD cars, magazine testers just find the sweet spot rpm, drop the clutch and let the tires spin for acceleration measurements. The slipping tires provide more grip than slipping clutches in most cars. I think that stock clutches are designed like this on purpose to keep from breaking transmissions.

Quote :The RWD cars are better now, but still FZ50 without TC or RA are much more dangerous and difficult to drive than comparable cars in RL (like Porsche e.g.)

Porche sets up their modern cars to have a significant amount of understeer. With all that mass at the back end, you don't want oversteer. Try drving a race prepped 911 and it will be a lot more sensitve.

Quote :I also noticed, that it is very hard to get your car drifting by suddenly take away throttle. Not because weight was transfered away from the back.

Weight transfer is normally the smallest factor with lift throttle oversteer. In a rear wheel drive car, lifting the throttle applies a braking torque to the rear wheels only, so they have less grip available for cornering. The differential setup can exaggerate lift throttle oversteer reaction. Except for low speed, low gear corners where there's a lot of engine braking torque, the weight transfer from lifting on the throttle isn't much, as the braking torque at the rear wheels is small in higher gears.

(Repeating myself, but how many here are finding it hard to believe I'm defending LFS's tire physics now?).
Quote from Niels Heusinkveld :Yes true.. Look at the different opinions on current sims. Simracing is very subjective.. some points:

blah blah blah

That is an extremely negative view, clearly you're a glass half empty person. First of all, do you actually have any real world racing experience?

What exactly are you expecting anyways? We have limited machines with limited hardware, and like it's some kind of divine revelation you draw the conclusion that the sim experience is limited on a PC... Excellent research

Whatever problems remain, I would bet that Scawen is far more aware of it than any of us. He's stated earlier that he's created test "software" to test the LFS tires under different conditions. Personally, I think he probably knows what he's doing. And if I was in his position, there is no reason to get involved in this discussion - he knows how LFS works and where it's weaknesses are already, and if his knowledge happens to contradict someone's opinion on this forum then all it generates is bad feelings. We already have had people telling them why their busniness model is poor. Should Scawen care? Obviously not.

In fact, based on your redundant essay above, we might as well not have opinions about LFS, since it's subjective. Guess what, opinions are by nature subjective, and so is experience. Since you cannot generate reality out of a PC, it will always be this way no matter what.

Here's the point:

Even if someone plopped on our hard drive today, a sim that was 100.0% perfect in every way conceivable, there would still be the RIP2004s and others that would be on the applicable forum, "explaining" why it was not right. All your essay proves is the fundamental human problem of perception within the limited tools we have to recreate a massive experience within tiny confines. In truth, of course it's not really possible. Excellent work discovering that!

Hopefully you don't think I am being rude, I'm just trying to get a point across. No matter what happens with any sim, people will always complain no matter what, period.

Edit: I am not trying to say LFS is perfect, but it's far more perfect than it was two days ago.
one more note concerning laptimes pre- and post s-patch:

could it be that the roadcars/streettires in general are slower now, whereas the racingcars/slicks in general are faster? I haven't tested it, but my impression from reading several posts about laptimes is just that. Anybody know more about this?

edit: oops, this post should actually have gone to the "first impressions" thread (damn tabbed browsing ). I guess I can't move it, can I?
Quote from JeffR :Depends on the tire compound. Some tires lose very little grip when slipping. A bit off topic here, but because of the slipping grip limitations of clutches in most RWD cars, magazine testers just find the sweet spot rpm, drop the clutch and let the tires spin for acceleration measurements. The slipping tires provide more grip than slipping clutches in most cars. I think that stock clutches are designed like this on purpose to keep from breaking transmissions.

That's correct. They find the sweet spot. If it was LFS, they would just floor the throttle and drop the clutch and it would be perfect. You need a certain amount of wheelspin but not that much.
The only car to start perfectly with this method is a AWD car ...

Note also that in race series there is a huge difference between starters. If it was LFS all would start equally with full throttle ...

It is a very old weakness, which is still there ... and most important it is tyre physics, which was one of the main topics of this update ... hope he will improve it again with next update
LFS *can* rule though, thats obvious. With normal front tyres, trying to do scandinavian flicks in the Fz50 is such a joy / challenge. It really doesn't want to just throw the back around, you have to do some serious provoking. This replay shows some non expert but still cool action imho.

Another very interesting thing might be TC. Now that you can have it on the Fz50, its kind of 'strange'. With an understeery setup and normal front tyres, you can provoke understeer: i.e. the car more or less goes straight. However, if you do that with TC enabled and your gas pedal to the floor, throttle will drop to 0% by the TC! So you're more or less going straight with loads of understeer, yet TC thinks there is 4% slip and cuts throttle? If TC on the Fz50 is cutting the throttle when rear wheelspin is >xx% then I'm not sure why front tyre understeer would lead to enough rear wheelspin to make the throttle stop completely... Who can explain that?

Of course if TC on the car acts when any of the wheels, driven or not driven, slip this is easy to explain..

Anyway even though I'm not that good yet this replay shows off the best side of LFS imo.
Attached files
Niels Heusinkveld_KY3_FZ5_5.spr - 96.9 KB - 255 views
Quote from Niels Heusinkveld :LFS *can* rule though, thats obvious. With normal front tyres, trying to do scandinavian flicks in the Fz50 is such a joy / challenge. It really doesn't want to just throw the back around, you have to do some serious provoking. This replay shows some non expert but still cool action imho.

Another very interesting thing might be TC. Now that you can have it on the Fz50, its kind of 'strange'. With an understeery setup and normal front tyres, you can provoke understeer: i.e. the car more or less goes straight. However, if you do that with TC enabled and your gas pedal to the floor, throttle will drop to 0% by the TC! So you're more or less going straight with loads of understeer, yet TC thinks there is 4% slip and cuts throttle? If TC on the Fz50 is cutting the throttle when rear wheelspin is >xx% then I'm not sure why front tyre understeer would lead to enough rear wheelspin to make the throttle stop completely... Who can explain that?

Of course if TC on the car acts when any of the wheels, driven or not driven, slip this is easy to explain..

Anyway even though I'm not that good yet this replay shows off the best side of LFS imo.

Do the front wheels turn more slowly under heavy understeer? If they do and the difference between the front and back wheel speed is what triggers the TC, then that could explain it.
Hmm yes that is probably it.
Quote from Niels Heusinkveld :But all seems to indicate that the actual tyre MODEL hasn't really changed! Only the parameters that feed it have gotten a bit better.

I feel quite strongly that this is not the case, actually. After having written several tire models for my own simulator and then driving and really analyzing the reactions on not just the seat of the pants, but also the numerical level, it feels very much to me as though Scawen has made a large leap forward in the model itself, specifically in regards to lateral/longitudinal force combination. I.e., when you're sitting at some slip angle and then change throttle/brake, the lateral force changes too.

Before this patch I really thought it was not right at all and was the cause of all these tire problems. However, to me it really appears to have been drastically improved. I've run my own models with and without these combination errors (took a very long time to figure out a way to do it properly) and the difference is really very similar as to what we see in the change with this new patch.

I haven't tested things too much yet, but after a few minutes playing around in the car park with some of the cars it's pretty obvious this part of the model has been changed, and in a very good way. Good job, Scawen

A lot of the discussion in this thread about handling quirks and so forth I think really can for the most part be attributed to the setup. You can engineer a real car to have lift-off oversteer or not, and so forth. That's what the setup is for and why suspension systems are adjustable. It's to allow you to adjust these under/oversteer tendencies in different situations. It's perfectly possible to build a real car that drives horribly, spins or doesn't spin when you hit the throttle, loses the back end or not on constant radius corners, and so on. That's chassis engineering and a great number of people make their livings at sorting that out with a real physics model (nature!)


Quote from Niels Heusinkveld :
I don't think you can say its 'high speed' or 'low speed'. This has often been mentioned in sims, and its true that most have different low speed physics.. but that is near 0 speed. Above 10km/h most sims will use their pacejkas or whatever model they run. Problems might be more apparant at certain speeds. At low speeds the car can change direction a bit faster, perhaps highlighting some issues with that. At high speed the car carries a lot of momentum which might cause different symptoms to show.

Yes, you're right about the high/low speed models. I don't know how it's handled in LFS and personally don't really care as the only time I drive that slow is after I inadvertantly punt someone off the track and wind up in the dirt next to him

Quote from Niels Heusinkveld :
How has he debugged LFS physics? How much situations has he put in the sim to calculate later by hand to see if weight transfer etc is 'close'? We all think its the tyres, and that is quite likely, but perhaps thats not the only thing..

Stuff like weight transfer and so on comes straight out of general rigid body dynamics calculations and you really can't get that wrong. As a result of the forces from the springs and so forth the weight transfer will just "happen correctly." I.e., there's no guessing or anything to check there.
Quote from Tyrion :Isn't part of the problem that people are actively seeking out and performing tests they know will show the weaknesses of the tire physics? It seems hardly an objective approach.You can find flaws in anything with that mindset.


No it is that people play the game and notice these things.
Quote from col :A clock that loses 1 second per day only shows the correct time every 236 years - a clock that has stopped completely shows the correct time every day.

col.

Ok, that's great, but I would rather have accurate look-up tables than incorrect real time calculations. edit- not implying either sim has any of those qualities.
Todd-

Thank you for the post, that was what we needed here... Someone with the arithmatic background and ability to analyse the recent updates to LFS. I could not agree more about the fact that setups affect what many self-appointed experts claim to be infallible evidence more than they realise.
Quote from jtw62074 :A lot of the discussion in this thread about handling quirks and so forth I think really can for the most part be attributed to the setup. You can engineer a real car to have lift-off oversteer or not, and so forth. That's what the setup is for and why suspension systems are adjustable. It's to allow you to adjust these under/oversteer tendencies in different situations. It's perfectly possible to build a real car that drives horribly, spins or doesn't spin when you hit the throttle, loses the back end or not on constant radius corners, and so on. That's chassis engineering and a great number of people make their livings at sorting that out with a real physics model (nature!)

Perfectly said!
Quote from Michael Denham :
Quote from jtw62074 :
A lot of the discussion in this thread about handling quirks and so forth I think really can for the most part be attributed to the setup. You can engineer a real car to have lift-off oversteer or not, and so forth. That's what the setup is for and why suspension systems are adjustable. It's to allow you to adjust these under/oversteer tendencies in different situations. It's perfectly possible to build a real car that drives horribly, spins or doesn't spin when you hit the throttle, loses the back end or not on constant radius corners, and so on. That's chassis engineering and a great number of people make their livings at sorting that out with a real physics model (nature!)

Perfectly said!

i did a lot of testing changing setups in every way even with extreme values, before speaking...to me seems that the handling problems arose here are related to this http://www.lfsforum.net/showthread.php?p=111845#post111845
#71 - axus
I think we need to see chassis flex modelled before we can asses the tyres much further - I think it might help the issue. There's been some pretty fine tuning going on with tyres and while the problem still exists under certain conditions it is close to being abolished. It has not merely been a case of changing a curve or two - as you see the tyre deformation has changed a lot so they must have looked at the roots of the problem. While LFS is still not perfect the problem is now quite easy to ignore because it doesn't appear under most driving scenarios that occur in proper racing. If you try to provoke it you will still get to it though.
Quote from axus :the problem is now quite easy to ignore because it doesn't appear under most driving scenarios that occur in proper racing. If you try to provoke it you will still get to it though.

actually is the contrary: it always show up too evidently in normal conditions, that's why i'm spending so much words, everyone is caught by the "BF1 fever" and nobody is testing the slower cars...the few glitches in tire phisics are ruining this patch wich is at 90% a huge improvement
Quote from Niels Heusinkveld :
Anyway even though I'm not that good yet this replay shows off the best side of LFS imo.

Exactly! It feels soo good to watch this kind of replays and admire this brutall physics engine..
#74 - axus
Quote from Honey :actually is the contrary: it always show up too evidently in normal conditions, that's why i'm spending so much words, everyone is caught by the "BF1 fever" and nobody is testing the slower cars...the few glitches in tire phisics are ruining this patch wich is at 90% a huge improvement

I find it happens on a far more rare ocassion now, before it had gotten to the stage that the problem was predictable. Now because you don't know the conditions which bring the same problem about, you don't know when to expect it so it seems like not much has changed but a lot has.
Quote from axus :I find it happens on a far more rare ocassion now, before it had gotten to the stage that the problem was predictable. Now because you don't know the conditions which bring the same problem about, you don't know when to expect it so it seems like not much has changed but a lot has.

i'm not sure i understood well what you say, but as i said in the other thread: take xfg put 2.2 bar and 3.5 camber (in RL you would never do such much) and drive around BL or SO at 50 kmh with F9 info and tell me if it is absurd or not

FGED GREDG RDFGDR GSFDG