The online racing simulator
Rfactor vs LFS
(1872 posts, started )
Quote from keiran :Don't think they do have the `rights` which is why they are not naming the real life tracks by there proper names. I still can't understand how they can get off with that

I'm also pretty curious about this. Nurburgring, Montreal, Barcelona and Monza are named after cities/towns but still the track is 1:1 with the real one. This have to have something to do with the Intel/BMW deal...
Quote from Blackout :no, wait...where's the catch?

its rfactor

Quote from axus :Can anyone who has it please upload the .tbc file here? Its only like 1 or 2kb and I don't want to download 160MB just to see it because I can't use it anyway.

from the bmw (the official one) ... every other tbc ive bothered to open looks the same

just posting the first few values but youll get the idea just by looking at the last one

[SLIPCURVE]
Name="LatSlip"
Step=0.009000 // Slip step
DropoffFunction=-0.10 // See explanation above
Data:
0.000000 0.174836 0.349483 0.518060 0.668882 0.790665 0.878928 0.936783 0.971287 0.989751
0.997978 1.000000 0.999632 0.998538 0.996690 0.994069 0.990622 0.986566 0.982162 0.977223
0.972191 0.967169 0.962158 0.957368 0.952395 0.947268 0.942100 0.937138 0.932347 0.927646
0.923216 0.918857 0.914620 0.909990 0.905347 0.900211 0.894754 0.888562 0.881919 0.874943
0.867751 0.860449 0.853111 0.845815 0.838611 0.831522 0.824611 0.817849 0.811257 0.804850
0.798539 0.792387 0.786377 0.780673 0.775277 0.770211 0.765415 0.760879 0.756604 0.752550
0.748670 0.744944 0.741404 0.737984 0.734717 0.731545 0.728464 0.725526 0.722667 0.719902
0.717246 0.714664 0.712174 0.709790 0.707439 0.705187 0.703003 0.700892 0.698841 0.696828
0.694901 0.693027 0.691223 0.689478 0.687770 0.686107 0.684496 0.682947 0.681417 0.679925
course it does, Intel/bmw use the ingame track at the actual track. im just not entirely sure whether the tracks are licensed or not.
Quote from Shotglass :values

Seen those. They're way off.

Way off as in more so than GTR2... probably in the region of 40%+ at points.

I wanted to see if that other mod's physics matched its graphics, but I'm not gonna get my hopes up.
Quote from axus :I wanted to see if that other mod's physics matched its graphics, but I'm not gonna get my hopes up.

ive only bothered to take a quick look at one of the tyre files and it falls off to 60-70% quickly as well
#406 - Woz
Quote from Sternendaal :Really,it does all I want from FFB. When driving in the grass,I feel every bump I drive over. At Lienz,driving over the cobblestones,I feel I am driving over that. I feel what the car does,that is all I want from FFB,right

The issue with ISI FFB is that it just triggers canned effects when a situation occurs in the car. This means something has to interpret the car state and decide which canned effect or combination of effects should be played at that moment.

LFS, RBR and NKP all transmit forces from the front tires up the steering column to create FFB. This is the reason for the strange ISI feeling that the FFB has turned off when you get understeer along with the other shortfalls in its FFB model.
Quote from Woz :LFS, RBR and NKP all transmit forces from the front tires up the steering column to create FFB. This is the reason for the strange ISI feeling that the FFB has turned off when you get understeer along with the other shortfalls in its FFB model.

DR (Driver's Republic) also uses steering column torque to create FF.
Quote from Shotglass :its rfactor

Haha, I know that but my point was that it does not look that special. And I guess its reguires a lot of harware to get it running like that, and if you lower the graphic settings so it maybe could run if it likes (until an another car shows up), it looks totally crap and I don't have a freking clue where is the track.

As you Sherlocks might guessed, yes I downloaded the demo (I gave it a second chance), forgive me mighty Blackwood Forestguru I never do it again. Only thing that I kinda liked were the extra noises the car made, all those bangs and whining was nice but the FF, it was horrible! It just doesn't feel right, I felt like I was floting in the air, and got no hints of oversteer, nothing. And it's just silly that people say "you need to do that, and that and edit it and plahplahplaa etc"to make it work nicely, that's not the way. I stick with LFS
Quote from Shotglass :ive only bothered to take a quick look at one of the tyre files and it falls off to 60-70% quickly as well

Here's a picture to give you a better idea. That's the lateral slip curve.

That is then scaled by the ISI engine according to this:
LatPeak=( 0.0827, 0.229, 15375.0)
so that the peak slip angle is at the value they want it to be.

What that means is that sin(peak slip angle) at 0N is 0.0827 - giving you a peak slip angle of 4.74 degrees. 0N is just a reference point - there is obviously no real peak slip angle at 0N because there is no side force. The other two values mean that sin(peak slip angle) at 15375N is 0.229. This comes down to a peak slip angle of 13.2 degrees at that load. The relationship between load and sin(peak slip angle) is linear in the ISI engine.

I hope that makes sense....
Attached images
rFactor BMW Slip curve.JPG
Quote from axus :I wanted to see if that other mod's physics matched its graphics, but I'm not gonna get my hopes up.

from the ctdp (the last two characters indicate the naughtyness of those curves) tyre files:

[SLIPCURVE]
Name="slip"
Step=0.009000 // Slip step
DropoffFunction=0.00 // See explanation above
Data:
0.000000 0.163355 0.343212 0.514209 0.662191 0.784381 0.873533 0.934627 0.970644 0.989714
0.997978 1.000000 0.999865 0.999478 0.998839 0.997952 0.996820 0.995447 0.993838 0.992000
0.989937 0.987659 0.985172 0.982486 0.979609 0.976552 0.973322 0.969932 0.966391 0.962709
0.958897 0.954965 0.950924 0.946785 0.942557 0.938251 0.933876 0.929442 0.924958 0.920432
0.915874 0.911292 0.906693 0.902084 0.897473 0.892866 0.888269 0.883688 0.879128 0.874595
0.870092 0.865624 0.861195 0.856808 0.852466 0.848173 0.843931 0.839741 0.835607 0.831529
0.827510 0.823550 0.819651 0.815813 0.812037 0.808324 0.804674 0.801087 0.797563 0.794103
0.790705 0.787371 0.784098 0.780888 0.777739 0.774651 0.771624 0.768656 0.765747 0.762895
0.760102 0.757364 0.754682 0.752055 0.749482 0.746961 0.744492 0.742074 0.739707 0.737388
0.735117 0.732894 0.730717 0.728585 0.726497 0.724453 0.722452 0.720492 0.718572 0.716693
0.714852 0.713050 0.711285 0.709556 0.707863 0.706205 0.704581 0.702990 0.701431 0.699904
0.698409 0.696943 0.695508 0.694101 0.692722 0.691371 0.690047 0.688750 0.687478 0.686231
0.685009 0.683811 0.682636 0.681484 0.680355 0.679247 0.678161 0.677095 0.676050 0.675025
0.674020 0.673033 0.672065 0.671115 0.670183 0.669268 0.668370 0.667489 0.666624 0.665775
0.664941 0.664123 0.663319 0.662530 0.661754 0.660993 0.660245 0.659511 0.658789 0.658080
Seems a few percent (read 3-6%) closer to reality than the ISI stuff but the LatPeak and LoadSens values are probably also off - they're easy to botch up and they vary more with the tyre and data about that is also hard to come by. Its effects on the feel are immense too. I've played around with those values a fair bit in GTR2 and the car can begin to feel like an underseering boat of a car, very unpredictable and unenjoyable to drive if they are off.

Just btw, if some of you are thinking "how do you know all this and claim that ISI don't" right now, my information comes from using the FTire trial to do some proper testing on tyres. That's a proper engineering model, simulating 1s of real time in about 20-30s of simulated time.
Quote from Blackout :And I guess its reguires a lot of harware to get it running like that, and if you lower the graphic settings so it maybe could run if it likes (until an another car shows up), it looks totally crap and I don't have a freking clue where is the track.

it looks just like the screenshots for me ingame. i can run at 1280x1024 2xAA and 8xAF with Adaptive anti-aliasing and still get an average of 50fps. and my pc is slightly below midrange...

Athlon XP 3000+ @ 2.2ghz
ATi Radeon X800gto (flashed to x800 XL and oc'ed about 10%)
768mb DDR ram (clocked somewhere between 2700 and 3200 speeds)
10 gigs of space left on hard drive.

with that mediocre setup i can run rfactor at very high settings.
Quote from axus :Seems a few percent (read 3-6%) closer to reality than the ISI stuff

doent help anyway ... such a dropoff amkes the cars completely uncatchable

if im not mistaken on how tyres act the only reason why lfs was driftable and catchable with the old "pronounced peak" curves is because they were completely flat past peak
I just cannot understand for the life of me why you need to edit text files to make a simulator feel more realistic. Think about it, logically that just doesnt make sense illepall
the people who made the game should already have everything optimized i agree... at least when it comes to physics..
Many racing tires, especially bias ply slicks reach a plateau instead of falling off when past peak slip angle. Here's one link with a generic graph of bias ply slicks versus a street radial:

http://www.sascosports.com/products/tire_info.htm

Modern radial slicks are becoming more forgiving. Hoosier Tire just recently released a radial slick racing tire optional replacement for their bias ply slicks.

I've seen other real data that doesn't show a lot of fall off in lateral grip versus slip angle until the load factor (downforce on the tire) gets high. Will see if I can find the graphs for this again.
Quote :This is the reason for the strange ISI feeling that the FFB has turned off when you get understeer along with the other shortfalls in its FFB model.

I had the impression that this was an assist to help a player know when the fronts where at the limit. I don't have the impression that this is trying to model reality, but just to make the cars more drivable at the limits, using a fudged FFB to compensate for the lack of feel. There may be a bit of reality to this effect, the reduction in torque at the wheel when slip angle is at or past the limits, but I don't think it's as extreme as it is in GTR.
Quote from DeKo :i just got a 21.6 for monza in the mcmerc, but thats after about 100 laps.

in other news, i think this screenshot is the best screen for a game ive ever seen:


http://img425.imageshack.us/im ... or2006090704251609jm3.jpg

I still think GP4 has the best graphics in most situations. Look at this and thats from a game nearly 5 years old that has no support for chrome effects...

Quote from Sternendaal :Really,it does all I want from FFB. When driving in the grass,I feel every bump I drive over. At Lienz,driving over the cobblestones,I feel I am driving over that. I feel what the car does,that is all I want from FFB,right

Well you want canned effects then. FFB effects which don't actually relate to exactly what the car is doing. How can you feel bumps through the steering wheel? You can't, you feel that through your body as the car vibrates, the only thing I can think of you'd feel through the wheel is it tugging the front wheels in dips etc. Sorry but those are purely for the immersion factor and I don't think of that as good FFB effects. Hell there not even well done from my experience, felt like I was driving through a mine field and all I had done was put two wheels on the grass

If I wanted that I'd go into windows controler setup and press the buttons on my wheel.
Quote : ... lat peak ...

Is there a real world source for this data or did someone just create a table or equation? I did a search for some real world data and could only come up with the link below, but it shows graphs from a real race car and it's tires showing that there is little or no fall off in grip versus slip angle, and it depends on the load factor (downforce). I remember some posts by Todd Watson who has researched this stuff quite a bit and he also stated that the loss of grip was minimal or not at all at higher slip angles (within reason).

http://www.smithees-racetech.com.au/ackerman.html
thx alot guys... my head is going to expload from all of this information :P
-
(KiDCoDEa) DELETED by KiDCoDEa
All this talk did make me want to try rFactor for myself.
downloaded the multiplayer test demo, loaded it, hit start.
Nothing. Did the firewall test, no connection, just endless waiting.
Checked the 'test forum' and didn't see specific info.
I'm not using a router, am using zone alarm.

Any suggestions ?
Quote from JeffR :Many racing tires, especially bias ply slicks reach a plateau instead of falling off when past peak slip angle. Here's one link with a generic graph of bias ply slicks versus a street radial:

http://www.sascosports.com/products/tire_info.htm

That "radial street tyre curve" looks like nothing I've seen. I wouldn't trust data that doesn't come with where it was measured, on what tyre, with what load etc. That's probably the reason why ISI sims' tyres are in that state - the developers believed tyre curves that someone drew in paint. Also note the lack of actual measurements on the degrees axis.
Quote from Flycantbird :All this talk did make me want to try rFactor for myself.
downloaded the multiplayer test demo, loaded it, hit start.
Nothing. Did the firewall test, no connection, just endless waiting.
Checked the 'test forum' and didn't see specific info.
I'm not using a router, am using zone alarm.

Any suggestions ?

really, really dont download the MP test demo. its soooo old, it shows nowhere near what rfactor is.
The goods and the bads in both games IMHO:

LFS:
+ Multiplayer, best netcode around for a racesim
+ Force Feedback, I can feel when the car will break out (using Black MOMO)
+ Wide range of cars (GT, Openwheel....)
+ Downloadable skins ingame, every user has his own space etc...
+ Very nice Community
+ Great feedback from the Devs

- No real life tracks, sorry, but this is a big minus for me . The tracks provided are very muck OK, but I really want to drive on real tracks
- LFS is using too much CPU power IMO


Rfactor:
+ Slightly better GFX engine, LFS is using too much CPU power instead of using more GFX card power
+ Wide range of good mods
+ " " good (real life) tracks

- Handling, FFB, I loose the cars too quick, I cannot feel when I will loose the car
- Not enough servers
Quote from Vultureke :
- LFS is using too much CPU power IMO

It can't not considering that the physics engine is from first principles about tyres, rather than just pulling data out of a table of values - atleast until PhysX cards come along.

Rfactor vs LFS
(1872 posts, started )
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