Racer 0.47

Is it me, or is this the coolest thing in a long time?

Sebastien, Undrivable? It has problems with the bumps in the original track (carrera) , however I suggest you try it on Surfers Paradise and you will be VERY surprised at the difference. Ashley "S�bastien Tixier" <[email hidden]> wrote in message news:9kb7r0$mjv$[email hidden]...

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| well, i think it's almost undrivable for now, but the idea is GREAT. | | IMO, there's works on suspension to do . | | -- | S�bastien TIXIER - Game Developer | Overall GPLRank -42.97 | Monster GPLRank -106.02 | | | "Pat Dotson" <[email hidden]> a �crit dans le message news: | [email hidden]... | > Is it me, or is this the coolest thing in a long time? | |

well, i think it's almost undrivable for now, but the idea is GREAT. IMO, there's works on suspension to do . -- S�bastien TIXIER - Game Developer Overall GPLRank -42.97 Monster GPLRank -106.02 "Pat Dotson" <[email hidden]> a �crit dans le message news: [email hidden]... > Is it me, or is this the coolest thing in a long time?

On Thu, 2 Aug 2001 10:52:43 +0100, "Ashley McConnell" <[email hidden]> wrote: >Sebastien, > >Undrivable? It has problems with the bumps in the original track (carrera) >, however I suggest you try it on Surfers Paradise and you will be VERY >surprised at the difference. Yes, although I never drive there actually, there's some huge differences between some of the cars (some of them are indeed undrivable). However, from experimenting with almost all of them I can see that it's in there (the physics engine) and just needs the right numbers. Which is ofcourse an art in itself. The Evo6 is very nice, as is the Ferrari 312. Still, it has that GPL touchy feeling, perhaps even more than GPL itself. :) The bumps in Carrera will only get better when the polygon subdivision is improved I'm afraid; it is a little TOO coarse. But it's a nice track to test on until you move on to bigger ones. And indeed, suspension is important, as is CG and roll centers. The Evo has really soft suspensions and drives ok on Carrera. I won't do any work on suspensions though, I'll stick to the sim programming part now that several people are working on the cars (and tracks). Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

Hi Ruud, speaking of tweaking; you know how hard it is to get any good Pacejka numbers, but could you just include a simple multiplier (say, Pacejka_factor ;) ) to multiply the Pacejka results (lateral, longitudinal force and aligning torque) with? The default should be 1, but to, say, increase the rear wheel grip (different spec tyres rear to front) you would put this simple factor in, as something like 1.05 would already change things dramatically? What do you think, to much of a fudge? -Gregor Ruud van Gaal wrote:

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> > Yes, although I never drive there actually, there's some huge > differences between some of the cars (some of them are indeed > undrivable). However, from experimenting with almost all of them I can > see that it's in there (the physics engine) and just needs the right > numbers. Which is ofcourse an art in itself. The Evo6 is very nice, as > is the Ferrari 312. Still, it has that GPL touchy feeling, perhaps > even more than GPL itself. :) > The bumps in Carrera will only get better when the polygon subdivision > is improved I'm afraid; it is a little TOO coarse. But it's a nice > track to test on until you move on to bigger ones. > And indeed, suspension is important, as is CG and roll centers. The > Evo has really soft suspensions and drives ok on Carrera. > > I won't do any work on suspensions though, I'll stick to the sim > programming part now that several people are working on the cars (and > tracks). > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

Next update needed: an internal controler calibration system. I have a home made 4 axis system (steering, gas, brake, clutch) and racer will only recognize the steering, gas, and the shifter buttons and even then the steering is reversed. I have tried to edit the ini files for the controlers with no success. From what I have seen so far of Racer, it's turing out to be something very close to GPL and with the constent updating I believe it'll far out do GPL in the not to distent future. (Can't wait for the multi player code:-) Mike Barlow

On Thu, 02 Aug 2001 14:41:49 +0200, Gregor Veble <[email hidden]> wrote: >Hi Ruud, > >speaking of tweaking; you know how hard it is to get any good Pacejka >numbers, but could you just include a simple multiplier (say, >Pacejka_factor ;) ) to multiply the Pacejka results (lateral, >longitudinal force and aligning torque) with? Hm, pacejka_factor.fx/fy and mz probably then. A nice idea, although I wonder whether just scaling a2/b2/c2 isn't enough. Probably isn't because why would the others be there. Hm. Interesting idea, a fudge, but a good fudge probably for practical use. I found that editing Pacejka numbers quickly gave me some inconsistent skidding sounds and all that. A Pacejka viewer/editor is still needed, but the factor might be in the next version. Thanks for the idea. :) And what do you think, multiply directly after calculating Fx/Fy/Mz or after your slip combination method? Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 02 Aug 2001 13:16:47 GMT, "Michael Barlow" <[email hidden]> wrote: > Next update needed: an internal controler calibration system. I have a >home made 4 axis system (steering, gas, brake, clutch) and racer will only >recognize the steering, gas, and the shifter buttons and even then the >steering is reversed. I have tried to edit the ini files for the controlers >with no success. Ah that one again. :) So the steering is reversed? Should be no problem, either switch the steerleft and steerright subtrees entirely, or swap the min/max values within those sections. So if you have 'min=0, max=-1000', make it 'min=-1000, max=0', though I don't think that will be your solution. Have you tried the Controller Peeker? With this you should be able to write down the numbers and be able to use them (as the code is largely the same in Racer as for the peeker). So if you turn left, and see '583' at axis X, and at center you see '10' (highly unusal numbers but for the idea), enter: steerleft { min=10 max=583 } Same with right steering, and probably you'll find min=10 as well (otherwise there would be no center) and max=-583 probably. > From what I have seen so far of Racer, it's turing out to be something >very close to GPL and with the constent updating I believe it'll far out do >GPL in the not to distent future. (Can't wait for the multi player code:-) AI & Multiplayer will be the toughest nuts to crack. Fortunately I think, a lot of cheaters won't be playing the game, since they'll all be playing NFS. This would make multiplayer life quite a bit easier (the first version will be oh so simple and have lag, syncing problems and the whole forest of problems probably hehe). But thanks for the compliment! :) v0.4.8 will probably have caster, thanks to Gregor (I should subtitle it Veble Racer, lol), mr. Formula Wizard. That's something GPL doesn't have. :) (but N4 does, ah well) And let's throw in some toe, should be easy enough, an offset. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

I also got another problem ... skids sound is always playing ! when we consider that skis helps you to drive because you can know if a tyre is sliping, that's another reason why it's very hard to drive ! I tried other tracks and other cars, it's easier to play, but IMO it's far from GPL "gameplay". Attention, i'm not saying your sims is craps ! i try it since some month, because, i'm doing car physics simulation for my job, and i saw lot's of improvement. I just tell my opinion to help you improve. Another question . do you have any setting to draw longitudinal and lateral forces forces and grip like there was on older version ? it was very intersting. I have the feeling that a main problem in your simulation is that you can block tyre too easily when breaking. and the main consequence is that you loose lateral grip on front tire and just can't turn. I try brake smoother with my guillemot FF, but din't manage not to brake too hard :o( Badly, i didn't find where to set up them in the carlab :o( Do you plan to make a replay ? have consider to record driver actions or cars position/rotation ? king regards, -- S�bastien TIXIER - Game Developer Overall GPLRank -42.97 Monster GPLRank -116.28 "Ruud van Gaal" <[email hidden]> a �crit dans le message news: [email hidden]... > On Thu, 2 Aug 2001 10:52:43 +0100, "Ashley McConnell" > <[email hidden]> wrote: > > >Sebastien, > > > >Undrivable? It has problems with the bumps in the original track (carrera) > >, however I suggest you try it on Surfers Paradise and you will be VERY > >surprised at the difference. > > Yes, although I never drive there actually, there's some huge > differences between some of the cars (some of them are indeed > undrivable). However, from experimenting with almost all of them I can > see that it's in there (the physics engine) and just needs the right > numbers. Which is ofcourse an art in itself. The Evo6 is very nice, as > is the Ferrari 312. Still, it has that GPL touchy feeling, perhaps > even more than GPL itself. :) > The bumps in Carrera will only get better when the polygon subdivision > is improved I'm afraid; it is a little TOO coarse. But it's a nice > track to test on until you move on to bigger ones. > And indeed, suspension is important, as is CG and roll centers. The > Evo has really soft suspensions and drives ok on Carrera. > > I won't do any work on suspensions though, I'll stick to the sim > programming part now that several people are working on the cars (and > tracks). > > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

Another question... do you simulate differential ( front, rear and central ) ? if not, this could be another reason why the car is so understeering and it's VERY diifcult to keep the car on road when you manage to oversteer the car. We saw at office that differntial is VERY important for the car handling... especialy on 4WD cars ! king regards, -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28 "Ruud van Gaal" <[email hidden]> a �crit dans le message news: [email hidden]... > On Thu, 2 Aug 2001 10:52:43 +0100, "Ashley McConnell" > <[email hidden]> wrote: > > >Sebastien, > > > >Undrivable? It has problems with the bumps in the original track (carrera) > >, however I suggest you try it on Surfers Paradise and you will be VERY > >surprised at the difference. > > Yes, although I never drive there actually, there's some huge > differences between some of the cars (some of them are indeed > undrivable). However, from experimenting with almost all of them I can > see that it's in there (the physics engine) and just needs the right > numbers. Which is ofcourse an art in itself. The Evo6 is very nice, as > is the Ferrari 312. Still, it has that GPL touchy feeling, perhaps > even more than GPL itself. :) > The bumps in Carrera will only get better when the polygon subdivision > is improved I'm afraid; it is a little TOO coarse. But it's a nice > track to test on until you move on to bigger ones. > And indeed, suspension is important, as is CG and roll centers. The > Evo has really soft suspensions and drives ok on Carrera. > > I won't do any work on suspensions though, I'll stick to the sim > programming part now that several people are working on the cars (and > tracks). > > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

Hi Ruud, I don't think it matters where exactly the multiplication takes place, as the result is the same. Do it as to keep the code as elegant as possible :). Basically, I believe the same should be possible by altering those Pacejka coefficients that deal with available grip, but just making a common factor would be much easier, and it would keep the 'hard' (to get ;) ) Pacejka coefficients intact. -Gregor Ruud van Gaal wrote:

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> > Hm, pacejka_factor.fx/fy and mz probably then. A nice idea, although I > wonder whether just scaling a2/b2/c2 isn't enough. Probably isn't > because why would the others be there. Hm. Interesting idea, a fudge, > but a good fudge probably for practical use. I found that editing > Pacejka numbers quickly gave me some inconsistent skidding sounds and > all that. > A Pacejka viewer/editor is still needed, but the factor might be in > the next version. Thanks for the idea. :) > > And what do you think, multiply directly after calculating Fx/Fy/Mz or > after your slip combination method? > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

i just tired the Ferrari 312, that's the most driveable car you got ! starting to have fun after some laps. i've seen a problem in suspension. When landing from the jump on the bridge the car start bouncing. I got the same problems some month ago, the dampers created force so big that they lifted the car, and that's IMPOSSIBLE, dampers can only void a suspension velocity , they can't negate them. I remember Gregor helped me a little with the formulas but the main idea was to predict if the force created by the dampers could negate the suspension veolicty, if so i decrease the damper force to only void the suspension velocity. hope that can help cheers, -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28 "Ruud van Gaal" <[email hidden]> a �crit dans le message news: [email hidden]... > On Thu, 02 Aug 2001 14:41:49 +0200, Gregor Veble > <[email hidden]> wrote: > > >Hi Ruud, > > > >speaking of tweaking; you know how hard it is to get any good Pacejka > >numbers, but could you just include a simple multiplier (say, > >Pacejka_factor ;) ) to multiply the Pacejka results (lateral, > >longitudinal force and aligning torque) with? > > Hm, pacejka_factor.fx/fy and mz probably then. A nice idea, although I > wonder whether just scaling a2/b2/c2 isn't enough. Probably isn't > because why would the others be there. Hm. Interesting idea, a fudge, > but a good fudge probably for practical use. I found that editing > Pacejka numbers quickly gave me some inconsistent skidding sounds and > all that. > A Pacejka viewer/editor is still needed, but the factor might be in > the next version. Thanks for the idea. :) > > And what do you think, multiply directly after calculating Fx/Fy/Mz or > after your slip combination method? > > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

[email hidden] (Ruud van Gaal) writes: > v0.4.8 will probably have caster, thanks to Gregor (I should subtitle > it Veble Racer, lol), mr. Formula Wizard. That's something GPL doesn't > have. :) (but N4 does, ah well) And let's throw in some toe, should be > easy enough, an offset. what the hell is this toe-thing, anyway? -- Gunnar #31 SUCKS#015 Tupperware MC#002 DoD#0x1B DoDRT#003 DoD:CT#4,8 Kibo�: 2 myk, trygg og god.

On Thu, 2 Aug 2001 18:18:34 +0200, "S�bastien Tixier" <[email hidden]> wrote: >i just tired the Ferrari 312, that's the most driveable car you got ! Lol, I almost thought you were being sarcastic. :) >starting to have fun after some laps. i've seen a problem in suspension. >When landing from the jump on the bridge the car start bouncing. There's a problem with collision detection that keeps bouncing the velocity off the surface if it stays IN the surface. Just worked on that and now it's possible to scrape the surface more, or well, it doesn't collide when you are LEAVING the geometry, so collisions are a lot better. But it may be the dampers that you saw...

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>I got the same problems some month ago, the dampers created force so big >that they lifted the car, and that's IMPOSSIBLE, dampers can only void a >suspension velocity , they can't negate them. > >I remember Gregor helped me a little with the formulas but the main idea was >to predict if the force created by the dampers could negate the suspension >veolicty, if so i decrease the damper force to only void the suspension >velocity.

Hm yes good tip! :) I'll see if I have bogus situations which lead to this. Must be near Chris' method of testing energy conversation in the shocks. Sometimes the wheels seem to get stuck in the upper compressed situation (which is probably what you mean) and only at a certain point they plop back again. Might have something to do with it. But in the mean time, they do press against the body in such a way that it seems to be able to fly or something. Thanks, Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 2 Aug 2001 17:41:13 +0200, "S�bastien Tixier" <[email hidden]> wrote: >I also got another problem ... skids sound is always playing ! when we >consider that skis helps you to drive because you can know if a tyre is >sliping, that's another reason why it's very hard to drive ! Weird, skid sounds are not always on here. What sound card do you have? Even then, I believe you can see the skidfactors on the left, and when added up they set a skid volume from 0..1. >Attention, i'm not saying your sims is craps ! i try it since some month, >because, i'm doing car physics simulation for my job, and i saw lot's of >improvement. >I just tell my opinion to help you improve. Yes, no offense taken, I've got some tough skin. :) Most criticism is right, although a lot ofcourse I already know and is on big tasklists here. >Another question . do you have any setting to draw longitudinal and lateral >forces forces and grip like there was on older version ? it was very >intersting. Yes, turn on debug.ini's stats.show_tire_forces. It is off by default now because more people start just racing it instead of being a freak of simming. ;-) >I have the feeling that a main problem in your simulation is that you can >block tyre too easily when breaking. and the main consequence is that you >loose lateral grip on front tire and just can't turn. I try brake smoother >with my guillemot FF, but din't manage not to brake too hard :o( Badly, i >didn't find where to set up them in the carlab :o( Carlab is really only used in my case for the car cameras. As for braking, this may be just the braking torque, which you can set in car.ini (data/cars/fer312/car.ini for example). Some cars can brake too hard so you're too quickly locking the fronts. Then there's a 2nd problem; I interpolate with negative slipratio's (from 0..1) the resulting force from purely lateral/longitudinal to the slipvelocity direction. Because when locking your tires ofcourse, the force direction = -slipVelocityDirection. However, I think this grows as you brake and brake harder, but perhaps I'm overdoing it and this is just an effect which appear at the limit of braking performance (say, slipRatio=0.9..1). I don't know. So basically it may start giving up steering control a bit too soon when braking. >Do you plan to make a replay ? have consider to record driver actions or >cars position/rotation ? Yes, replays are very important, just to review the great moments, and for a ghost car too. I'll record car positions, since the system is so complex that I'd rather just store the pos/rot variables. Esp. if you change the car physics a bit (like inertia values), your replays would become unusable if you just stored driver inputs. Cheers, Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

you'r welcome, there so much works to do to program a good car physics :o) With my colegue, we worked 8 hours a day for several month, on the one we made for our game at work, and we still have some works on ground resistive force , when "uploading" information from tire to engine through gearbox and differentials :o) regards, -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28

On Thu, 2 Aug 2001 17:56:06 +0200, "S�bastien Tixier" <[email hidden]> wrote: >Another question... do you simulate differential ( front, rear and central ) >? Just 1 rear diff. I know for 4WD you have to have 3. How do you handle 3 interacting differentials? Is it a mess or a clean pipeline of differentials in your simulation? >if not, this could be another reason why the car is so understeering and >it's VERY diifcult to keep the car on road when you manage to oversteer the >car. You can change the differential in the car.ini; mainly the locking is important. It's a viscous diff, with a locking coefficient set to 100 by default. Values from 0 (open) to 200 (locking hard) may be realistic and useful, but I did little experimenting. >We saw at office that differntial is VERY important for the car handling... >especialy on 4WD cars ! Certainly! Makes a whole lot of difference. One of the primary handling things in the cars. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 02 Aug 2001 17:09:43 GMT, Gunnar Horrigmo <[email hidden]> wrote:

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>[email hidden] (Ruud van Gaal) writes: > >> v0.4.8 will probably have caster, thanks to Gregor (I should subtitle >> it Veble Racer, lol), mr. Formula Wizard. That's something GPL doesn't >> have. :) (but N4 does, ah well) And let's throw in some toe, should be >> easy enough, an offset. > >what the hell is this toe-thing, anyway?

It's rotating the wheels inside (toe in) or outside (toe out), in the center of steering position. Seems to add some stability to turn-ins. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

> Yes, replays are very important, just to review the great moments, and > for a ghost car too. I'll record car positions, since the system is so > complex that I'd rather just store the pos/rot variables. Esp. if you > change the car physics a bit (like inertia values), your replays would > become unusable if you just stored driver inputs. we store the car with quaternions every 10 frames ( 60 fps ) and interpolate values, works great :) -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28

"Ruud van Gaal" <[email hidden]> a �crit dans le message news: [email hidden]... > On Thu, 2 Aug 2001 17:41:13 +0200, "S�bastien Tixier" > <[email hidden]> wrote: > > Weird, skid sounds are not always on here. What sound card do you > have? Even then, I believe you can see the skidfactors on the left, > and when added up they set a skid volume from 0..1. I just check, i have skidding sound even with 0 skidfactors. I have a sound blaster live deluxe with liveware 3 and Win2000, setup with 4 speakers. -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28

On Thu, 2 Aug 2001 20:10:40 +0200, "S�bastien Tixier" <[email hidden]> wrote:

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> >> Yes, replays are very important, just to review the great moments, and >> for a ghost car too. I'll record car positions, since the system is so >> complex that I'd rather just store the pos/rot variables. Esp. if you >> change the car physics a bit (like inertia values), your replays would >> become unusable if you just stored driver inputs. > >we store the car with quaternions every 10 frames ( 60 fps ) and interpolate >values, works great :)

That's 6Hz then? I had thought of 10Hz, or in any case something that may be quite the same as the multiplayer network frequency. (I believe Quake uses 20Hz network frequency) Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

oups, i forgot to say that we worked on PS2, so we don't have memory to waste ;o) we got only 32mb to store every thing, track included !!! We try with only 3fps but the interpolation was not strong enough and the car handled strangely in the replays :o) But it's a lot more that on the PS1 wich had only 2mb !! on PS1 we were forced to store user controls each frame and compress them in real time because storing car informations ( position, rotation, wheel angle, suspension stroke, tire grip for GFX/SFX) was really too much memory, so in fact the replay was a replay of the driver not a movie :o)... so we didn't have a "rewind" button in our replay :o) well, got to go to sleep, tomorow i'll have 12hours of road drive,to go to Espana for my 2 weeks vacancies. Don't work to hard look at the sun sometimes ;o)))) cheers, -- S�bastien TIXIER - Game Developer Dynamics and Car Physics Overall GPLRank -42.97 Monster GPLRank -116.28 "Ruud van Gaal" <[email hidden]> a �crit dans le message news: [email hidden]... > On Thu, 2 Aug 2001 20:10:40 +0200, "S�bastien Tixier" > <[email hidden]> wrote: > > > > >> Yes, replays are very important, just to review the great moments, and > >> for a ghost car too. I'll record car positions, since the system is so > >> complex that I'd rather just store the pos/rot variables. Esp. if you > >> change the car physics a bit (like inertia values), your replays would > >> become unusable if you just stored driver inputs. > > > >we store the car with quaternions every 10 frames ( 60 fps ) and interpolate > >values, works great :) > > That's 6Hz then? I had thought of 10Hz, or in any case something that > may be quite the same as the multiplayer network frequency. (I believe > Quake uses 20Hz network frequency) > > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

Hmm, I definitely don't find it undrivable. It's definitely not ready for prime time, but generally speaking I'd place in on a level with GPL and N4 in terms of providing a feel for the handling of the car. The one biggest place that I see RACER shining is in the way the front wheels catch oversteer. I've never gotten that feeling from any other sim in the way I do from this one. The force feedback is pretty much as good or better than anything else. I think it's more responsive than anything else. -- Pat Dotson "S�bastien Tixier" wrote: > > well, i think it's almost undrivable for now, but the idea is GREAT. > > IMO, there's works on suspension to do . > > -- > S�bastien TIXIER - Game Developer > Overall GPLRank -42.97 > Monster GPLRank -106.02 > > "Pat Dotson" <[email hidden]> a �crit dans le message news: > [email hidden]... > > Is it me, or is this the coolest thing in a long time?

Do any of the cars currently available have front wheel drive? For a while I thought the Evoc did, but now I just think it's underpowered :) -- Pat Dotson Ruud van Gaal wrote: > > On Thu, 2 Aug 2001 17:56:06 +0200, "S�bastien Tixier" > <[email hidden]> wrote: > > >Another question... do you simulate differential ( front, rear and central ) > >? > > Just 1 rear diff. I know for 4WD you have to have 3. How do you handle > 3 interacting differentials? Is it a mess or a clean pipeline of > differentials in your simulation? > > >if not, this could be another reason why the car is so understeering and > >it's VERY diifcult to keep the car on road when you manage to oversteer the > >car. > > You can change the differential in the car.ini; mainly the locking is > important. It's a viscous diff, with a locking coefficient set to 100 > by default. Values from 0 (open) to 200 (locking hard) may be > realistic and useful, but I did little experimenting. > > >We saw at office that differntial is VERY important for the car handling... > >especialy on 4WD cars ! > > Certainly! Makes a whole lot of difference. One of the primary > handling things in the cars. > > Ruud van Gaal, GPL Rank +53.25 > Pencil art : http://www.marketgraph.nl/gallery/ > Free car sim : http://www.marketgraph.nl/gallery/racer/

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>Yes, although I never drive there actually, there's some huge >differences between some of the cars (some of them are indeed >undrivable). However, from experimenting with almost all of them I can >see that it's in there (the physics engine) and just needs the right >numbers. Which is ofcourse an art in itself. The Evo6 is very nice, as >is the Ferrari 312. Still, it has that GPL touchy feeling, perhaps >even more than GPL itself. :) >The bumps in Carrera will only get better when the polygon subdivision >is improved I'm afraid; it is a little TOO coarse. But it's a nice >track to test on until you move on to bigger ones. >And indeed, suspension is important, as is CG and roll centers. The >Evo has really soft suspensions and drives ok on Carrera. > >I won't do any work on suspensions though, I'll stick to the sim >programming part now that several people are working on the cars (and >tracks). > >

Not a bad idea. I currently have to write routines to allow the other programmer on my project to design an interface for car setup. Displaying/adjusting something simple like ride height or camber angle at static ride height gets really complicated when the suspension is modelled more fully with A-arms, inclined spring/shock angles, etc.. Besides, GPL does suspensions the same way you're doing it from what I've heard so far, sooo..... :-) Todd Wasson --- Performance Simulations Drag Racing and Top Speed Prediction Software http://PerformanceSimulations.Com

[email hidden] (Ruud van Gaal) writes:

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> On Thu, 02 Aug 2001 17:09:43 GMT, Gunnar Horrigmo <[email hidden]> > wrote: > >[email hidden] (Ruud van Gaal) writes: > > > >> v0.4.8 will probably have caster, thanks to Gregor (I should subtitle > >> it Veble Racer, lol), mr. Formula Wizard. That's something GPL doesn't > >> have. :) (but N4 does, ah well) And let's throw in some toe, should be > >> easy enough, an offset. > > > >what the hell is this toe-thing, anyway? > > It's rotating the wheels inside (toe in) or outside (toe out), in the > center of steering position. Seems to add some stability to turn-ins.

you mean like this? toe in toe out / ---- \ \ ---- / | | | | | | |--------| |--------| -- Gunnar #31 SUCKS#015 Tupperware MC#002 DoD#0x1B DoDRT#003 DoD:CT#4,8 Kibo�: 2 myk, trygg og god.

Wow, vehicle aerobics :). Yes, that should be it. -Gregor Gunnar Horrigmo wrote:

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> > you mean like this? > > toe in toe out > > / ---- \ \ ---- / > | | > | | > | | > |--------| |--------| > > -- > Gunnar > #31 SUCKS#015 Tupperware MC#002 DoD#0x1B DoDRT#003 DoD:CT#4,8 Kibo�: 2 > myk, trygg og god.

On Thu, 2 Aug 2001 21:33:37 +0200, "S�bastien Tixier" <[email hidden]> wrote: >oups, i forgot to say that we worked on PS2, so we don't have memory to >waste ;o) we got only 32mb to store every thing, track included !!! >We try with only 3fps but the interpolation was not strong enough and the >car handled strangely in the replays :o) Geez, I don't envy you. I just allocate memory as it comes. If a good method requires more memory, so be it. That's the fun when you're making a sim that doesn't have a base machine config behind it. :) >well, got to go to sleep, tomorow i'll have 12hours of road drive,to go to >Espana for my 2 weeks vacancies. You'll probably miss this one, but happy holidays! >Don't work to hard look at the sun sometimes ;o)))) Not too much of that around here now. :( But a good rule of life. :) Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 02 Aug 2001 16:35:52 -0500, Pat Dotson <[email hidden]> wrote: >Do any of the cars currently available have >front wheel drive? For a while I thought >the Evoc did, but now I just think it's >underpowered :) Yes, at 0 rpm it does have quite little torque. You might want to edit torque.crv. You can make it front wheel drive by setting wheel0.powered=1 and wheel1.powered=1 (and taking out wheel2.powered (=0) and wheel3 ofcourse). Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 02 Aug 2001 16:28:01 -0500, Pat Dotson <[email hidden]> wrote:

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>Hmm, I definitely don't find it undrivable. It's >definitely not ready for prime time, but generally >speaking I'd place in on a level with GPL and N4 >in terms of providing a feel for the handling of >the car. > >The one biggest place that I see RACER shining is >in the way the front wheels catch oversteer. I've >never gotten that feeling from any other sim in >the way I do from this one. The force feedback >is pretty much as good or better than anything else. >I think it's more responsive than anything else.

Can I quote you in a commercial? ;-) Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On 03 Aug 2001 00:42:03 GMT, [email hidden] (J. Todd Wasson) wrote:

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> Not a bad idea. I currently have to write routines to allow the other >programmer on my project to design an interface for car setup. >Displaying/adjusting something simple like ride height or camber angle at >static ride height gets really complicated when the suspension is modelled more >fully with A-arms, inclined spring/shock angles, etc.. Besides, GPL does >suspensions the same way you're doing it from what I've heard so far, sooo..... >:-)

Good thing. :) Actually, all these links are better probably but I've got too many suspensions to simulate I think. I want more gameplay in at the moment, and add physics tweaks on the side. Still, a novel (well) idea I have is to give some engineering info on a setup, so to display for example (in a report or something) the amount of damper damping (over/underdamped) to help in setting up a bit realistically. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

On Thu, 2 Aug 2001 20:36:13 +0200, "S�bastien Tixier" <[email hidden]> wrote:

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> >"Ruud van Gaal" <[email hidden]> a �crit dans le message news: >[email hidden]... >> On Thu, 2 Aug 2001 17:41:13 +0200, "S�bastien Tixier" >> <[email hidden]> wrote: >> >> Weird, skid sounds are not always on here. What sound card do you >> have? Even then, I believe you can see the skidfactors on the left, >> and when added up they set a skid volume from 0..1. > >I just check, i have skidding sound even with 0 skidfactors.

If you're still around, make sure in debug.ini your friction_circle_method=3. Otherwise, skid factors are not calculated right (not calculated at all). And as it doesn't get set in the ctor, it's random, thus either no sound or some sound or whatever! Bug will be fixed in v0.4.8. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

In article <[email hidden]>, [email hidden] (Ruud van Gaal) writes:

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> On Thu, 2 Aug 2001 17:41:13 +0200, "S�bastien Tixier" > <[email hidden]> wrote: > >>Do you plan to make a replay ? have consider to record driver actions or >>cars position/rotation ? > > Yes, replays are very important, just to review the great moments, and > for a ghost car too. I'll record car positions, since the system is so > complex that I'd rather just store the pos/rot variables. Esp. if you > change the car physics a bit (like inertia values), your replays would > become unusable if you just stored driver inputs. >

On the other side, using user input could ease the debugging process. Users would send their replay, instead of describing as accurately as they can (which is often not much). Another advantage is that you can write an analyser using the same simulation engine and a saved set of inputs. Why not using both methods ? saving states at regular intervals would be ideal to allow replays to be consistent over evolutions of the sim engine. For performance analysis and debugging, the input method is the best IMO. -- Johann Deneux Kart simulator: http://www.esil.univ-mrs.fr/~jdeneux/projects/top10/

It reminded me of Homer :) - Toe goes in.....Toe goes out Toe goes in.....Toe goes out Toe goes in.....Toe goes out Toe goes in.....Toe goes out Toe goes in.....Toe goes out :) Ash "Gregor Veble" <[email hidden]> wrote in message news:[email hidden]...

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| Wow, vehicle aerobics :). | | Yes, that should be it. | | -Gregor | | Gunnar Horrigmo wrote: | > | > you mean like this? | > | > toe in toe out | > | > / ---- \ \ ---- / | > | | | > | | | > | | | > |--------| |--------| | > | > -- | > Gunnar | > #31 SUCKS#015 Tupperware MC#002 DoD#0x1B DoDRT#003 DoD:CT#4,8 Kibo�:

2 | > myk, trygg og god.

On 5 Aug 2001 12:52:23 GMT, [email hidden] (Johann Deneux) wrote: >On the other side, using user input could ease the debugging process. >Users would send their replay, instead of describing as accurately as >they can (which is often not much). Haven't heard of bugs that aren't already blatantly obvious and are on my tasklists already, and the bugs that may be in there are so subtle that's it's hard to feel that it's a bug (i.e. perhaps a '-' sign in the differential code for example). >Another advantage is that you can write an analyser using the same >simulation engine and a saved set of inputs. That's true, although those graphs sweeping up & down indicating how far you pressed the throttle never seemed to make sense to me. Not without a visual feedback like in GPL Replay Analyser where you SEE where you lose time, and then want to see if there was any difference in throttle/brake pedal position for example. I'll consider it, perhaps indeed as an option, so you can exclude it and save space, which is a biggy for replays. Ruud van Gaal, GPL Rank +53.25 Pencil art : http://www.marketgraph.nl/gallery/ Free car sim : http://www.marketgraph.nl/gallery/racer/

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>Good thing. :) Actually, all these links are better probably but I've >got too many suspensions to simulate I think. I want more gameplay in >at the moment, and add physics tweaks on the side. >Still, a novel (well) idea I have is to give some engineering info on >a setup, so to display for example (in a report or something) the >amount of damper damping (over/underdamped) to help in setting up a >bit realistically.

Possibly, but for the most part, there's either McPherson strut or A-arms on the cars simmers will be interested in. Aside from solid axles, of course. An online engineer is a great idea for helping folks with setups. Tough to do though, but it'd be helpful. For dampening, you could calculate critical dampening and show that rate, or a range around it. Todd Wasson --- Performance Simulations Drag Racing and Top Speed Prediction Software http://PerformanceSimulations.Com