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Raven9000

Shaky ground and sky?

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I have a weird issue with XP 10...

 

For starters, the ground beneath me seems to "shake"...

 

I will start a flight, be sitting at a runway, and the ground just.. shakes..!

 

Note that this is not some aircraft effect, or whatever. The aircraft is cold and dark, and this is still happening...

 

The shaking is pretty evident and even more so because it's as if two ground "tiles" were moving between each other...

 

 

Then the second issue is the sky. Tried a night one to check out XP's famous lighting. To my surprise, the sky in front of me, stars, etc., seems to "tremble"? Tried at dusk and a little less but still noticeable, although the night one is VERY annoying...

 

Does anyone have a clue about this? I took two simple videos but the files are too huge to upload, will see if I can upload to Youtube or something.

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I think I know what you mean and this I believe is related to floating point accuracy with textures which make them appear to shake. It's something I've just learned to ignore unfortuanetly and never found anything that seems to stop in (Maybe someone else has had more luck)

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Well sadly I just can't ignore it.. :)

 

But this is crazy, why on earth does this happen here and not in any other game or sim?

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It's not due to textures drawing, it's due to instabilities arising when modeling static friction that make the aircraft shake on the ground.

 

Infact, if you press the 'c' key to go to free camera mode, the shaking will stop.

 

Other flight simulators probably use different methods that avoid this issue, however modeling ground interaction is always difficult and different issues may be present.

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I noticed a lot when I was developing airports which had multiple overlayed ground textures, the textures would appear to shake. I've also never noticed this in other games either


It's not due to textures drawing, it's due to instabilities arising when modeling static friction that make the aircraft shake on the ground.

 Are you sure? I am pretty sure I saw a post about this issue from LR and I've never been able to make it stop

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I noticed a lot when I was developing airports which had multiple overlayed ground textures, the textures would appear to shake. I've also never noticed this in other games either

 Are you sure? I am pretty sure I saw a post about this issue from LR and I've never been able to make it stop

 

Hmm.... Maybe there are two different but similar issues... However the OP said the sky is shaking as well, that lets me think that the culprit is the whole aircraft shaking. If that is the case, the reason is the one I described.

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It's not the aircraft. If I switch to an outside view the ground shakes as well...

 

I will try to upload to yt.

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The external view is tied to the aircraft, so if the aircraft is trembling, the view will trembe as well.

 

Try this: press the 'c' key, the trembling should stop. If that happens, the reason is the one I described.

 

You could try the following and see if things improve: go to the "Settings"->"Operations & Warnings" menu, then increase the "flight model per frame" to a higher value (let's say, 4 or 5). Check if the trembling disappears.

 

Be advised a very high "flight model per frame" setting can cause a decrease in FPS.

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The external view is tied to the aircraft, so if the aircraft is trembling, the view will trembe as well.

 

Try this: press the 'c' key, the trembling should stop. If that happens, the reason is the one I described.

 

You could try the following and see if things improve: go to the "Settings"->"Operations & Warnings" menu, then increase the "flight model per frame" to a higher value (let's say, 4 or 5). Check if the trembling disappears.

 

Be advised a very high "flight model per frame" setting can cause a decrease in FPS.

Thanks, I will try these tips out.

 

For the record though, it's not the view that trembles. It's just parts, likein my example thefloor tiles or the sky/stars. The rest of the scenery is perfect.

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I notice this on occasion too, but more in the manner that Tony describes, in that it's overlaid textures appearing to shake slightly in relation to the aircraft which seems stationary. However, for me it is always tied to the aircraft view, in that when you go into free camera 'C' mode, everything is always firm / stationary.  Building / inspecting scenery would be a royal pain if not so...

 

I've never given it a great deal of thought however. It's more noticeable in stuff like helicopters, where you can clearly the ground textures moving in relation to the skids.

 

The moment you start to move or takeoff however, you're focused elsewhere and personally, I never consider it again.

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I think Tony could be right then. I wonder why it seems to disappear when using the free camera view.

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This has been pointed out but there is no fix. 

And from the responses given from LR, I wouldn't expect one anytime soon. Their basic response was that it's a flight simulator, not a ground simulator. 

As someone who uses P3D and XP10, that kind of rubbed me the wrong way. Taxing, pre-flights, etc. are part of flying and this problem isn't just isolated to the ground. You'll also see flashing/tearing on some airport buildings with this bug. 

 

Pressing C fixes it, so those speculating it's related to the aircraft views are correct. 

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Their basic response was that it's a flight simulator, not a ground simulator.

 

Which is kind of ironic, since with the movement controls so nicely usable in free camera mode it does the best darn job of being an 'outside the aircraft' simulator as well. I map the view controls to a gamepad, and using free camera mode, it's like having access to a First Person Walking Simulator.

 

But of course, in free camera mode, the shaking issue isn't present, so then it's not an issue. :wink:


 

 


You'll also see flashing/tearing on some airport buildings with this bug.

 

I always thought that was unrelated - I thought that's the same type of z-fighting that's related to texture mapping on models. Or having two mapped textures on different planes placed extremely close to each other, that share a plane as you view them from farther away and begin to flicker.

 

That one happened frequently on FSX models, and I recall it affected overlaid ground textures badly in certain scenery, depending on the method used to create the scenery.

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Ok, so I tried your suggestions, and sure enough...

 

Pressing the 'c' key to go into that mode shows all the exterior perfectly, no shaking contrary to any view (in or outside the aircraft)

 

I made two very short videos that are too big to attach here, but small enough for you to see (one is 30MB the other is 90MB). Here are the links:

 

https://www.dropbox.com/s/83b9kuqe153t7tm/Alabeo_C172RG_3.avi?dl=0

 

https://www.dropbox.com/s/ku6y7difwwc6qe4/Alabeo_C172RG_4.avi?dl=0

 

 

the first is my view through the side window, and the second has 2 similar outside views of the plane, one using one of the "regular" views and the second with the 'c' key mode.

 

 

By the way, you'll also notice in the video my second problem, which is that the shadows look terrible and extremely jagged!!! I tried all sorts of settings to fix this, because I have seen other people's pics and videos where the shadows are very smooth and crisp, but with no luck.

 

Anyone know about that?

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Which is kind of ironic, since with the movement controls so nicely usable in free camera mode it does the best darn job of being an 'outside the aircraft' simulator as well. I map the view controls to a gamepad, and using free camera mode, it's like having access to a First Person Walking Simulator.

 

But of course, in free camera mode, the shaking issue isn't present, so then it's not an issue. :wink:

 

 

I always thought that was unrelated - I thought that's the same type of z-fighting that's related to texture mapping on models. Or having two mapped textures on different planes placed extremely close to each other, that share a plane as you view them from farther away and begin to flicker.

 

That one happened frequently on FSX models, and I recall it affected overlaid ground textures badly in certain scenery, depending on the method used to create the scenery.

It's related. Going to C mode stops it just like the ground shaking. I think it's part of the overlays shaking and the seams crossing or something similar.

 

You can see it really badly at KMEM, which I think is a stock global airport now. Most airports don't do it though.

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I think it's part of the overlays shaking and the seams crossing or something similar.

 

Yep, if you have a scenery that overlays textures on top of each other (e.g. dirt marks or concrete cracks) they appear to jidder. I never noticed that the camera mode wasn't effected, generally when I'm developing an airport I pan around the aircraft and the jiddery overlays can be quite evident. It was explained to me at the time that the issue was that UV coordinates for textures (being floating points) aren't 100% precise so they shift/jidder slightly, although it seems strange that the issue goes away when in free-camera mode.

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Odd... I haven't seen this lately, at least on my current rig. Everything is very stable and smooth, no difference between in-cockpit or "C" camera view. 

 

Where do you have your "flight models per frame" set? Are you using more than one flight model iteration per frame, or just one? And what's your average frame rate? I'm wondering if this might have something to do with the shaking, if it goes away when you hit the "C" camera view.

 

FWIW, I have my system set at 2 flight models per frame, and typically running high 30's to mid 40 fps with average clouds, up to 50 fps with clear sky. No shaking at all, on ground or stars.

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Odd... I haven't seen this lately, at least on my current rig. Everything is very stable and smooth, no difference between in-cockpit or "C" camera view. 

 

Where do you have your "flight models per frame" set? Are you using more than one flight model iteration per frame, or just one? And what's your average frame rate? I'm wondering if this might have something to do with the shaking, if it goes away when you hit the "C" camera view.

 

FWIW, I have my system set at 2 flight models per frame, and typically running high 30's to mid 40 fps with average clouds, up to 50 fps with clear sky. No shaking at all, on ground or stars.

 

I've seen it at framerates from 30's to 50's. And I have my 'flight models per frame' set at 3, mainly because somewhere I read that's better for flying helicopters. No idea if it helps in that regard, but the flight model is very smooth. :wink: 

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Odd... I haven't seen this lately, at least on my current rig. Everything is very stable and smooth, no difference between in-cockpit or "C" camera view. 

 

Where do you have your "flight models per frame" set? Are you using more than one flight model iteration per frame, or just one? And what's your average frame rate? I'm wondering if this might have something to do with the shaking, if it goes away when you hit the "C" camera view.

 

FWIW, I have my system set at 2 flight models per frame, and typically running high 30's to mid 40 fps with average clouds, up to 50 fps with clear sky. No shaking at all, on ground or stars.

I have tried all values from 1 to 10... nothing changes at all...

 

Frames I have vsync set right now and are pretty much locked at 30

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The flight models per frame option was suggested years ago in regards to this problem. It's not a solution and has no effect. 

 

This problem has been officially acknowledged finally (in the past year even though it's existed a lot longer). There is no fix.

 

It shouldn't keep you from flying XP, but just know it's there, it's not going away, and try your best to forget about it.

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The ground shaking I could forget about it, won-t see it for log anyway. But the night sky (which is constantly in my windshield...) that's not that easy to do...

 

Kind of defeats the purpose of XP's superior lighting...

 

And another thing I can-t get by is the jagged shadows... this is just supposed to be me (I think) but I don-t know how to fix it.

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Luckily, I haven't noticed the night sky shaking. Hopefully, I don't.

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The flight models per frame option was suggested years ago in regards to this problem. It's not a solution and has no effect. 

 

This problem has been officially acknowledged finally (in the past year even though it's existed a lot longer). There is no fix.

 

It shouldn't keep you from flying XP, but just know it's there, it's not going away, and try your best to forget about it.

 

Okay, but what explains the fact that some people like me aren't experience it? It may be a problem for some, but it certainly isn't universal. My views are completely steady, in and out of the cockpit, anywhere I fly and land.

 

If it's happening for some people and not others, then there must be an explanation related to either different hardware being used, or different settings in the sim.

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The ground shaking I could forget about it, won-t see it for log anyway. But the night sky (which is constantly in my windshield...) that's not that easy to do...

 

Kind of defeats the purpose of XP's superior lighting...

 

And another thing I can-t get by is the jagged shadows... this is just supposed to be me (I think) but I don-t know how to fix it.

 

any chance you can make a video of this?

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