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Alec

Trying to achieve the Dream of Smooth Stutter Free Simming

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...So what's the implications if I want to use 30fps fixed on my PC instead of 20? First I need 60+ fps showing most of the time in unlimited, requiring a PC with 3/2 the current available throughpu

 

Steve, your answer makes a lot of sense to me and clarifies a lot of doubts. Does it work the same way with P3D2 as well? Because in that case the best solution for me appears to set it limited @20 until I have the hardware to step up to 30 and so on ....

 

Andrea

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The sim is designed from the ground up to use look ahead frames with the locked fps setting. The unlimited setting is basically a test mode for performance comparison. When we set locked fps in the sim this instructs the sim to use look ahead frames. It is not the same as capping the frame rate with the monitor refresh or GPU limiter. The problem with locked fps is that it takes time to build a look ahead buffer. When we have a look ahead buffer there are pre rendered frames that fill in when the scene complexity increases too much for the rendering to keep up.

 

and therein lies the whole core of the problem. Trying to make look ahead frames for something flying through 3D space - where at any moment things can change. Yeah it's great when you fly straight and level and don't pan your view, but the second you plug in a TrackIR the virtual accelerations and decelerations  associated with head movement will also dramatically impact the  calculations required to render that image on screen. When you start looking around and maneuvering the aircraft the look ahead buffer is all but useless.

 

edit: Nvidia driver defaults to 3 I believe

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Not sure if you've tried it, by I use TrackIR with perfect results.

 

For TIR to work, and panning, and flying turns, we need a consistent time between frames. The pre rendered frames are there to ensure the next frame is delivered in a consistent time. So at 20fps 0.15s is adequate for that purpose. Running TIR with unlimited or a locked frame rate that cannot be maintained, pass me the sick bag.

 

and therein lies the whole core of the problem. Trying to make look ahead frames for something flying through 3D space - where at any moment things can change. Yeah it's great when you fly straight and level and don't pan your view, but the second you plug in a TrackIR the virtual accelerations and decelerations  associated with head movement will also dramatically impact the  calculations required to render that image on screen. When you start looking around and maneuvering the aircraft the look ahead buffer is all but useless.

 

edit: Nvidia driver defaults to 3 I believe

If you think pre rendered frames is going to help the sim keep going during an almost hung I/O transfer loading a one million facet overcount airport, forget it. But when the sim calculates where your plane is going to be in the next frame, you're better off with the time between frames being consistent and predictable, believe me.


Steve Waite: Engineer at codelegend.com

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Which is one of the reasons I keep P3D locked at 20 and don't bother with the FPS counter. As long as it is SMOOTH, I really don't care what the fps is nor can I tell if it's changing. the only time I can notice fps fluctuations is when I look at the fps counter.

 

 

Vic


 

RIG#1 - 7700K 5.0g ROG X270F 3600 15-15-15 - EVGA RTX 3090 1000W PSU 1- 850G EVO SSD, 2-256G OCZ SSD, 1TB,HAF942-H100 Water W1064Pro
40" 4K Monitor 3840x2160 - AS16, ASCA, GEP3D, UTX, Toposim, ORBX Regions, TrackIR
RIG#2 - 3770K 4.7g Asus Z77 1600 7-8-7 GTX1080ti DH14 850W 2-1TB WD HDD,1tb VRap, Armor+ W10 Pro 2 - HannsG 28" Monitors
 

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I know my thinking on this one is probably not smart but with almost 2000$ rig in 2015 I'm kinda reluctant in running anything at 20FPS.


Officially I don't believe there are many. I guess not many people really want to or have to need to run at 30Hz. It appears that some of the 4k and high res displays have this option. 

 

Maybe ask this question over on the Monitor forum and you could probably also get more technical insight about running your monitor at 30Hz.

 

Michael M

 

I guess I'll have to wait for those happy days a little longer. When I change the refresh rate and press Test button the monitor goes black and a box with a message appears:" Not Optimum Mode". I have a Samsung 23", a couple of years old. Apparently there is no way to override that, at least Google didn't present me with any usable advice :sad: I'll ask the question on the monitor forum.

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I know my thinking on this one is probably not smart but with almost 2000$ rig in 2015 I'm kinda reluctant in running anything at 20FPS

Why? Is FPS a badge of honor of some kind? It would appear that you don't want VISUAL performance in your sim but would rather just get good "numbers".

 

I would take MY smooth 20fps over anyone's choppy 60 any day.

 

I really laugh because I see so many people posting " I can easily get 60fps - but sometimes I get blurries or micro stutters".

 

What is the point in high FPS if you get stutters and/or blurries??  It really makes no sense. I believe the problem really stems from the fact that most people equate high fps with smooth operation. That is absolutely NOT true.

 

You need to find that point on your system where you get the smoothest performance overall REGARDLESS of fps.

 

Frankly, if most users would disable the fps counter they would probably enjoy their sim a lot more.

 

Tune it to be SMOOTH and forget the FPS - there is NO difference between smooth at 20fps and smooth at 60 fps - PERIOD.

 

If you say you can tell the difference - then one of them is not smooth.

 

Get your head out of the FPS trap and enjoy your sim.

 

:)

 

Vic


 

RIG#1 - 7700K 5.0g ROG X270F 3600 15-15-15 - EVGA RTX 3090 1000W PSU 1- 850G EVO SSD, 2-256G OCZ SSD, 1TB,HAF942-H100 Water W1064Pro
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Why? Is FPS a badge of honor of some kind? It would appear that you don't want VISUAL performance in your sim but would rather just get good "numbers".

 

I would take MY smooth 20fps over anyone's choppy 60 any day.

 

I really laugh because I see so many people posting " I can easily get 60fps - but sometimes I get blurries or micro stutters".

 

What is the point in high FPS if you get stutters and/or blurries??  It really makes no sense. I believe the problem really stems from the fact that most people equate high fps with smooth operation. That is absolutely NOT true.

 

You need to find that point on your system where you get the smoothest performance overall REGARDLESS of fps.

 

Frankly, if most users would disable the fps counter they would probably enjoy their sim a lot more.

 

Tune it to be SMOOTH and forget the FPS - there is NO difference between smooth at 20fps and smooth at 60 fps - PERIOD.

 

If you say you can tell the difference - then one of them is not smooth.

 

Get your head out of the FPS trap and enjoy your sim.

 

:)

 

Vic

I'd really like to agree with you but I can't. Maybe the smoothness when looking sideways or turning is better at 20 FPS (in P3D) because no microstutters but when I use TrackIR I can absolutely see the difference between 20 and 60 FPS. I big difference when looking around. You don't notice how much more fluid it is at higher FPS or maybe you don't use TIR? Well, I'll try to enjoy what I have, I'll even give your 20FPS a try for a few days to see how it works. Maybe some of those problems will be solved in the v3 :) But that's something for another thread in the forums :)

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You don't notice how much more fluid it is at higher FPS or maybe you don't use TIR?

I always fly with TIR - I use the trackclip pro version. I have heard others with the same complaint as you but I don't have this issue. Perhaps there's extraneous light or something like that? I DID have some trouble with TIR a while back where if I turned my head a little too far, it would hang and speed up etc. Tracked it down finally - at certain times of the day, the sun reflected off a bookcase in just the right place to confuse TIR.

 

The trick will be getting it smooth. Once you think you have it, start lowering the FPS and work down to whatever is the lowest setting you can get on your system. If you find the optimum lowest setting, that frees up your system to process other things with less interference.

 

There should be no fluctuations in the FPS, other than the small 19.9 - 20 or 29.9 - 30 that you see. If it is going 14 - 20 or 25 - 30 - it is NOT smooth. I have never seen either FSX or P3D stay constant 20 or 30 or 60 without moving at least .1.

 

Just for kicks - have someone else set the fps limit so you don't know what it is. Turn OFF the fps counter and fly. See if you can tell which setting you have.

 

 

 

Good luck -

 

Vic


 

RIG#1 - 7700K 5.0g ROG X270F 3600 15-15-15 - EVGA RTX 3090 1000W PSU 1- 850G EVO SSD, 2-256G OCZ SSD, 1TB,HAF942-H100 Water W1064Pro
40" 4K Monitor 3840x2160 - AS16, ASCA, GEP3D, UTX, Toposim, ORBX Regions, TrackIR
RIG#2 - 3770K 4.7g Asus Z77 1600 7-8-7 GTX1080ti DH14 850W 2-1TB WD HDD,1tb VRap, Armor+ W10 Pro 2 - HannsG 28" Monitors
 

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+1 Vic. That's it Vic.. That's only reason I look at the FPS to see if how much the numbers are moving. Once I found that I know p3d is smooth. Any micro stutters or pauses I know it coming from something else. Then I do what you said " Turn OFF the counter and fly." I have no problem with TIR either. Good flightsim wisdom Vic.


Maurice J

I7 7700k 4.7 \ EVGA 1080ti \ G-Skill 32GB \ Samsung 4K TV

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Tune it to be SMOOTH and forget the FPS - there is NO difference between smooth at 20fps and smooth at 60 fps - PERIOD.

 

Absolutely false, for me, but I'm sure there are a lot of other people who would agree with me.

 

Just for kicks - have someone else set the fps limit so you don't know what it is. Turn OFF the fps counter and fly. See if you can tell which setting you have.

 

Good luck -

 

And that's exactly what I did just now. :smile: I did a blind test: I made 3 identical fsx.cfg with the only difference being the FPS limit (20, 30 or 60 FPS). Then I made 30 copies of them. Then I randomly renamed each of them, pressing random letters on the keyboard. Then I picked at random 10 of them, and ran FSX with each one of them in sequence, one by one. After each test, I noted on each filename my perceived frame rate (either 20, 30 or 60).

 

Here's the results I obtained:

 

picked a total of 5 fsx.cfg set at 20 FPS - correctly guessed all of them;

 

picked a total of 2 fsx.cfg set at 30 FPS - correctly guessed all of them;

 

picked a total of 3 fsx.cfg set at 60 FPS - correctly guessed 2 out of 3 of them. On the last one I was undecided if it was 30 or 60, I made a guess of 30.

 

So, I can say without a doubt that the difference between 20 FPS and, say, 40 FPS is for me night and day. The difference between 30 and 60 FPS is less discernible, but it's there, especially if the game is very smooth. Infact, for me stutters tend to level out the difference between frame rate.

 

Honestly, 20 FPS were immediately discernible. Not only that, but it gave me a very displeasant sensation just at the moment of takeoff rotation. Turns and any kind of maneuver were unpleasant as well.

 

Personally I consider 20 FPS an immersion killer. Unfortunately, having a low rig, sometimes I'm forced to fly at such low FPS, but I consider that just a big compromise to enjoy nicer eye candy. I know for a fact that my FPS threshold is somewehere around 35-40 FPS, above those FPS I feel the movement is really smooth. 20 FPS is horrible for me! :smile:

 

I urge any of you to do the same test (shortened): just make 2 copies of your fsx.cfg, set one at 20 FPS and the other at 60 FPS. Of course, you must use a situation where you can get 60 FPS (e.g. with low display settings and a default aircraft). Then, rename at random each of the two, use them in sequence to do a test flight, and now tell me you can't discern between the two!


"The problem with quotes on the Internet is that it is hard to verify their authenticity." [Abraham Lincoln]

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Simply put - your test proves my point - which you missed -

 

it's BLACK and WHITE - smooth or not smooth - PERIOD.

 

if you saw a difference then the LOWER settings were NOT smooth - period.

 

Get it SMOOTH at 20 and you will not be able to tell the difference. You can see a difference because it is not smooth. See my point?

 

Let's say in spot view the nose of your a/c is at the left of the screen - it will not get to the right side any faster at 60fps than at 20fps.

 

I acknowledge that each system is different - perhaps on your system you cannot get it smooth at 20 - then for you, a higher figure is better.

 

All I am really saying is for people to try to get the LOWEST fps they can with the SMOOTHEST performance - this will give them the best results. Chasing FPS for the sake of FPS is what causes most of the problems I read in the various forums. Chase SMOOTHNESS and let the fps fall where they may.

 

The worst thing that MS ever did was to include a FPS counter - in flight sims it is almost irrelevant except for benchmark fans.

 

Vic


 

RIG#1 - 7700K 5.0g ROG X270F 3600 15-15-15 - EVGA RTX 3090 1000W PSU 1- 850G EVO SSD, 2-256G OCZ SSD, 1TB,HAF942-H100 Water W1064Pro
40" 4K Monitor 3840x2160 - AS16, ASCA, GEP3D, UTX, Toposim, ORBX Regions, TrackIR
RIG#2 - 3770K 4.7g Asus Z77 1600 7-8-7 GTX1080ti DH14 850W 2-1TB WD HDD,1tb VRap, Armor+ W10 Pro 2 - HannsG 28" Monitors
 

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Remember CRTs switching between 60, 70, 80, 90, most people found it pretty straight forward to notice the change to the monitor, whatever the frequency set. So long as it didn't beat with the strip lights it was cool.

 

But I don't see frequency as being part of what makes the sim appear smooth, so long as it's over 19fps, were we naturally blur one image into the next in our own vision.

 

Those are two separate things.

 

For the sim to appear smooth without micro-stutters the updates need to appear in time with the monitor refresh and be above 19 fps, 20 will do fine, 30 might be good if the hardware can support it fully. A few look ahead frames ensure that timing between frames can remain very consistent with most of the concurrent things going on to upset the flow in the background. I used 15fps for years with FSX and lesser hardware, TIR and no sick bags filled.


Steve Waite: Engineer at codelegend.com

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Simply put - your test proves my point - which you missed -

 

it's BLACK and WHITE - smooth or not smooth - PERIOD.

 

if you saw a difference then the LOWER settings were NOT smooth - period.

 

Get it SMOOTH at 20 and you will not be able to tell the difference. You can see a difference because it is not smooth. See my point?

 

Let's say in spot view the nose of your a/c is at the left of the screen - it will not get to the right side any faster at 60fps than at 20fps.

 

I acknowledge that each system is different - perhaps on your system you cannot get it smooth at 20 - then for you, a higher figure is better.

 

Hmmm no, you're wrong, at least with regard to my perceptions - PERIOD (as you say).

 

You proposed a test, and I showed you that I can clearly discern between 20 and 60 FPS. Not only, but I find 20 FPS displeasant to fly at, notwithstanding the smoothness. Again, I urge anyone reading this thread to try themselves the shortened test I described in my previous post. You could aso try it yourself, vgbaron! Have you tried it?

 

However, since it's just my word, I propose another test. You stated that in your case, you have a very smooth 20 FPS. So we can arrange something like that: make two short youtube videos of your P3D, one at 20 FPS and the other at 60 FPS (exactly those 2 values). Make just a takeoff and some lively maneuvers in the air with a default aircraft.

 

Of course some conditions must be met: the situation and settings must be such that you can achieve steady 60 FPS _AND_ be able to record at such frame rate at a decent resolution (say, 480 pixels vertical). Then, upload the two videos on youtube (at 60 fps, of course), and see if I can discern between the two. :smile:

For the sim to appear smooth without micro-stutters the updates need to appear in time with the monitor refresh and be above 19 fps, 20 will do fine, 30 might be good if the hardware can support it fully. A few look ahead frames ensure that timing between frames can remain very consistent with most of the concurrent things going on to upset the flow in the background. I used 15fps for years with FSX and lesser hardware, TIR and no sick bags filled.

 

Good for you. Maybe I have a much finer sensibility to movements. Of course smoothness is very important, but for me, 20 fps or less feels very unpleasant, whatever the smoothness.

 

So I propose the same test to you: you state that you're fine with 15fps. Good. So, set your P3D in a situation that gives you 60 fps. Now switch between the two: 15 fps and 60 fps. Just do a takeoff and some maneuvers in each case.

 

Then come back here and tell me your impressions. :smile: I will accept it if you say that you don't notice the difference or that 15 fps are fine and feel smooth for you. Just please, all of you, should accept that for many of people, 15 or 20 fps feel very ugly, unpleasant, and immersion killing. You can't decide what feels smooth or realistic for me, really. :smile:

 


"The problem with quotes on the Internet is that it is hard to verify their authenticity." [Abraham Lincoln]

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I've been playing with 30fps and settings pushed down to accomplish it, but it's still too rich for my 4.1GHz 3960x GTX680. What I need is a 7GHz 9960x and GTX1280. :Praying:

 

Hmmm no, you're wrong, at least with regard to my perceptions - PERIOD (as you say).

 

You proposed a test, and I showed you that I can clearly discern between 20 and 60 FPS. Not only, but I find 20 FPS displeasant to fly at, notwithstanding the smoothness. Again, I urge anyone reading this thread to try themselves the shortened test I described in my previous post. You could aso try it yourself, vgbaron! Have you tried it?

 

However, since it's just my word, I propose another test. You stated that in your case, you have a very smooth 20 FPS. So we can arrange something like that: make two short youtube videos of your P3D, one at 20 FPS and the other at 60 FPS (exactly those 2 values). Make just a takeoff and some lively maneuvers in the air with a default aircraft.

 

Of course some conditions must be met: the situation and settings must be such that you can achieve steady 60 FPS _AND_ be able to record at such frame rate at a decent resolution (say, 480 pixels vertical). Then, upload the two videos on youtube (at 60 fps, of course), and see if I can discern between the two. :smile:

 

 

Good for you. Maybe I have a much finer sensibility to movements. Of course smoothness is very important, but for me, 20 fps or less feels very unpleasant, whatever the smoothness.

 

So I propose the same test to you: you state that you're fine with 15fps. Good. So, set your P3D in a situation that gives you 60 fps. Now switch between the two: 15 fps and 60 fps. Just do a takeoff and some maneuvers in each case.

 

Then come back here and tell me your impressions. :smile: I will accept it if you say that you don't notice the difference or that 15 fps are fine and feel smooth for you. Just please, all of you, should accept that for many of people, 15 or 20 fps feel very ugly, unpleasant, and immersion killing. You can't decide what feels smooth or realistic for me, really. :smile:

 

Anyone can see the difference in frequency:

 

Remember CRTs switching between 60, 70, 80, 90, most people found it pretty straight forward to notice the change to the monitor, whatever the frequency set. So long as it didn't beat with the strip lights it was cool.

It's just not worth being fixated on a high number of images per second, a number that can't be met by these simulators unfortunately. Playing doom maybe I'll hit more enemies at 60Hz than 30Hz. But P3D, and FSX are just not treated like those games in their design. From the ground up they are designed to run low fps, like 20, with a look ahead buffer, because they don't run like twitch games at all. Even internal concurrent processes of the sim don't run at frame rate. Increasing the frame rate also increases stresses from addons that respond to frame events, just not cool.


Steve Waite: Engineer at codelegend.com

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I've been playing with 30fps and settings pushed down to accomplish it, but it's still too rich for my 4.1GHz 3960x GTX680. What I need is a 7GHz 9960x and GTX1280. :Praying:

 

 

It's just not worth being fixated on a high number of images per second, a number that can't be met by these simulators unfortunately. Playing doom maybe I'll hit more enemies at 60Hz than 30Hz. But P3D, and FSX are just not treated like those games in their design. From the ground up they are designed to run low fps, like 20, with a look ahead buffer, because they don't run like twitch games at all. Even internal concurrent processes of the sim don't run at frame rate. Increasing the frame rate also increases stresses from addons that respond to frame events, just not cool.

 

I'm not "fixated" on high FPS, as you seem to suggest. I'm simply stating a few simple, true facts, that I demonstrated. That is, I'm very sensible to the frame rate in a certain range, and I find frame rates of about 20 or less quite unpleasant (and unrealistic) to fly with. Neverthless, I sometimes fly with such low fps, for the eye candy. However, I can't deny that I get a more pleasant feeling during flight and piloting, if FPS is greater than about 35 or so.

 

Maybe you can fly at 15 fps and find that absolutely pleasant, and equivalent to 60 fps? Well, it's good for you, really! :smile:

Maybe you think that FPS shouldn't be the only priority? Good, and I even agree!

 

But what I'm against, is making assertions that there is no difference between 20 FPS and 60 FPS (smoothness being the same): it has been stated in this thread, and that's the reason that provoked my reply.

 

If you want, I'd tell you that for me 15 fps and 60 fps are almost identical, and that I find very pleasant to fly at 15 fps, but unfortunately I cannot lie to myself!


"The problem with quotes on the Internet is that it is hard to verify their authenticity." [Abraham Lincoln]

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