The online racing simulator
Twice FPS rate ?
(71 posts, started )
Ok then what is there, in my posts that you don't understand ?
TBH, at 75 Hz, no more thant 75 frames can be shown. So it must be your settings. LFS runs totaly smooth for me (compared to ISI games). Indeed, get another Pole () and talk to him so he can explain. And post ALL your settings - in the driver (if you're using a special profile for LFS like i am - everything maxed out for the best quality) and in the game.
Things I have understood by now:
1. You get a lot of FPS.
2. Your monitor can only display 75 FPS, because of the 75Hz refresh rate

Thing I haven't understood:
1. What it is you want? You seem to want more FPS, which doesn't make sense because you already have plenty, so much infact it wouldn't make a difference because your monitor can't display all of them even now.
2. What is this smoothness you keep referring to? If you have 180 FPS it should by smooth.
3. What is this "double frame rates" you keep referring to? You can't just double the framerates of a game like that, it needs a lot of optimizing. Besides LFS is very optimized already, which makes it even more difficult.

Things I think you could be referring to:
1. You want the car to move fast like in the video. If you mean this, it's not dependant on the FPS. It has everything to do with the FOV of the game (how wide the viewable area of the game is). Wider FOV increases sense of speed. You can increase your FOV in the options (View - Field of view).
#31 - w126
#32 - J.B.
Quote from vixer :Guys please dont tell me LFS doesnt need an engine improvement .

There is indeed a difference between LFS and rfactor or whatever it is. LFS always does two small frame steps followed by one big one, the other game is smoother. I wonder if you're onto something there. What were vsynch settings for the games?
#33 - w126
Quote from J.B. :LFS always does two small frame steps followed by one big one, the other game is smoother.

It makes sense now. LFS performs 100 steps of physical simulation per second. This doesn't match the display refresh rate of 75 Hz. Two frames are done after every physics step, then the third one after two physics steps.
#34 - J.B.
Ah, right. Should have noticed that myself. So basically 60 Hz LCDs are a bit crap for LFS. 50Hz would probably be better but I don't think they exist...

I always thought it was the difference between 100 and Hz and 60 Hz that made LFS seem less smooth on LCD vs CRT but now it seems it's not just that.

Maybe it's time for LFS to switch it's physics engine to 120 Hz?
Finaly, i was getting worried that im the only per to see it . Settings for both games where identical 75hz ref and vsyn on. Yes W126 tryied it all. Uncle Benny if u think im going on whit this for nothing then just have a go in M3 challenge (or gtr,2,rfak,F1) turn on vsync on your desire refresh and do a couple of circles and then say again that LFS doesnt need an engine imp. Now wer getting somewhere, but wont it be beter just to make the physics engine refresh it self like the graph engine ? For 75hz ref, 75 refreshes of the physisc engine, for 60hz, 60 ref and so on.. ?
#36 - J.B.
No, instable physics fps is one of ISI's biggest problems. LFS has constant physics fps which means that the physics are always identical, no matter what fps the graphics are running at. That is also what makes the spr replay system work.

In rfactor you have different physics quality depending on your graphics frame rate.
So that is it, this game wont be "smooth" untill the engine is build in a propper way .
So basically have to get an 100hz crt, are the refresh cycles at least synchronized ?
J.B. you have an 100hz crt and the secong game is smoother then ur LFS ?
#38 - J.B.
Why isn't constant physics rate proper? Maybe constant 1000 Hz would be more proper than 100 Hz but I don't know if current CPUs could handle that. More of a Monitor problem IMO, CRTs are just better in some ways.

I haven't used my CRT since I got this LCD so I can't answer your question about the second game but since I got the LCD I do find myself glancing at the fps counter every now and then because it just isn't as smooth as it used to be.

BTW I just used Powerstrip to force my LCD to 50 Hz and it worked. But AA/AF stopped working so I uninstalled PS again. Not worth the hassle.
I dont know but im pretty sure that refresh cycles of engines should be synchronized .
Physics engines and GFX engines are not the same thing.
I have watched the videos, re read all the posts, Im thinking that vixer is getting some kind of stuttering or maybe tearing? but its not shown clearly in the videos, at least not using my monitor/PC

I have been an ATI fanboy for years and reading this, and seeing screenshots from other NV users, I wont be buying any NV GFX when I next get a chance to upgrade Im all for quality over FPS quantity

I do hope we all find out what the problem is and help Vixer fix it tho really interesting thread

That would be very nice .But why does it happen only when the car is in motion ? When i stop the car and i can see the work of suspension then the game runs perfectly smooth .
#42 - J.B.
Quote from SparkyDave :
I have watched the videos, re read all the posts, Im thinking that vixer is getting some kind of stuttering or maybe tearing? but its not shown clearly in the videos, at least not using my monitor/PC

Open the clip in virtualdub and go through it frame by frame. You should see that the step sizes in LFS are irregular.
Yes, some sort of frame skipping but it only occurs while car is changing position, when is stands in one and it wiggles then its fine .
OK gone through the clips with Vdub frame by frame, and indeed the scenery skips 1 frame in 4, so it goes 1 2 4 5 6 8 9 10 12 etc if it only occurs when scenery is moving accross the screen (when turning) I would guess if it clears when turning Vsync off, it could be some problem with the GFX card trying to send frame3, but by the time its about to be displayed frame 4 gets the ok signal, and gets displayed instead. Interestingly the FPS display seems to be mainly at 74.8 when the next frame is displayed and @ 75.1 on the "good frames" but that is probably coincidence.

Vixer just to clafiry, what display are you using?
Are you using the displays "native resolution"?
are you using a good quality DVI cable?
what version Nvidia drivers?
did you uninstall and remove (with the tool) the old ATI drivers?
does this happen with AA + AF on and off?
Is your GFX card overclocked?
do you have your frame rate limited in game? (options misc) try limiting it to a value higher than 75. (try 100 for example)
does this happen @16bit and 32bit resolutions?


(why is this thread not in Tech Ass? its not like Scawen can make 75Hz Vsync PC's display 150fps its just not possible )
Quote :the scenery skips 1 frame in 4, so it goes 1 2 4 5 6 8 9 10 12

Isn't that what happens anyway when you run at 75hz on a LCD? From what I read LCDs only truly run at 60hz, so the last frame is cut in half or something.
IIyama prolite E430
Yes native 1280x1024x75hz
The cable that came whit display
Iv tried whit the drivers from driver-cd and the newest from Nv site
After removing the ati card the system disk was formated more then 10 times
Yes no mather what res what in game settings and what filtering
Its the same whit GFX o/c and cpu o/c or not
No, limiter is off no mather if on limit
Yes it does on 32 and 16 refresh doesnt mather neither
Without vsync its much beter but i get frame tearing so its also not good.
So why are you blaming LFS for your vsync issues? As with most things, there's always a tradeoff. With vsync on, you tend to get skipped frames. As you've noticed, having it off results in smoother motion but also tearing. That's the tradeoff.

If you notice tearing in LFS with vsync off, you're probably spinning out.
Because i have this issue only in LFS .
Do you have vsync turned on in LFS or the drivers? Or both? I don't think there should be a difference but there may.
No mather if i turn it on in game or force in Nv panel .

Twice FPS rate ?
(71 posts, started )