[BUG LOGGED] Excessive LOD pop-in after SU5

Since the latest sim update, I have noticed quite a drastic increase in external LOD pop-in.

When looking out of the cockpit window I can now see buildings, trees and even mountains suddenly appear within the first few moments of panning the camera around, and it’s really jarring. This also occurs while using the external camera.

The sim update seems to have introduced an aggressive form of occlusion culling (a feature that disables the rendering of objects when they are not currently seen by the camera) which in turn has substantially improved performance. However I think this has also made the environment much less pleasing to explore as you are constantly seeing objects appear around you.

I am also seeing taxiway signs and airport traffic suddenly appear into view too.

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There was a closed thread on this in general, but I think it was closed because people were having arguments for no reason, and someone was claiming this isn’t an issue.

I personally love the general performance boost and I can live with this culling issue, but having an option to adjust it would be nice. Most culling in other games loads much faster, so I wish just like world streaming that we could set a maximum RAM amount to use for culling.

However, the biggest issue for me is: Previously I was getting about 25-28 FPS in an A320 at KLAX with stutters, and about 20-23 FPS when looking around. Now I get a much smoother 30-36 FPS, but when I look around (even in the cockpit), it drops to 15-18 FPS. Still kinda smoother than before, but very noticable.

I know that just like many other aspects of the sim, we will probably get used to these performance drops, but we will see. I even get this FPS drop when looking up and down to interact with the overhead and FMC. Having sliders/toggles/options would be great.

I also can only imagine that this is worse for VR users when they turn their head, but I haven’t had a chance to try that yet.

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Unfortunately it is not a bug, according to Asobo it is an intended side effect of this new culling technique (which brought a massive 3x memory reduction and improved CPU performance). We’re seeing pop-in and stutters while panning the camera or switching views because the simulator is constantly loading and unloading assets into memory.

Since it’s not unintended behaviour, I believe it might be more worthwhile to request a slider that allows us to adjust the amount of scenery that’s being culled, with the option to completely disable it as well. If it’s hard-coded it might not be possible to let the user tone down this behaviour, so I hope the community asks for it and that they’ll respond soon.

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I’m surprised they weren’t able to allow you to keep the assets in memory, even if it’s not rendering them and if limited by a max RAM amount you set. Isn’t that the standard practice? Should theoretically allow for the same performance benefits with no stutter or lag when turning the camera.

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Indeed, most games that employ frustum culling keep assets in memory so they can be rendered again in an instant when they come into view. I guess that Asobo decided to constantly unload assets because at times the simulator did require tons of RAM (which wouldn’t have allowed it to fit into the Xbox), but I really wish they’d allow us to reduce the amount of culling or set a max RAM limit if possible. Users of both low-end and high-end systems will be pleased if there’s enough adjustability.

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I am not seeing the benefit here…if we now see popups when panning from left to right…scenery that was just there…now redraws itself over and over agian while panning…this looks horrible IMO.

This may not be an issue for folk who look straight ahead but VR and TrackIR users greatly affect by this…

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It could kill the game for me which is sad because except for some bugs it was near perfect for realistic VFR flying.

My FPS was fine before and the landscapes were so realistic. Now I have to wait until I’m a few miles away for them to load in. And the gray blobs that turn into houses as you get close. God.

So now I have two options:

  1. Turn on BING data and watch all that awful looking terrain until I get close where it suddenly loads in the BING overlay.
  2. Turn off bind data and have the terrain lot a fraction as good as it did before.

Talk about my worst fears. I was hoping XBox would get a PC user experience. Instead, they clobbered the PC experience so XBox would work.

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It looks really bad and has pretty much killed my desire to play the game. I’m not a hardcore flight simmer, I’m here mainly for the sights/exploring as the world looks so pretty in this game… or rather it did until this jarring pop in started occurring.

I’m glad for the performance boost but I think I’d have rather stuck with the worse performing but much prettier looking visuals we had before.

Pop in is a major immersion killer. Meh

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I flew around the LA area this afternoon and it looked fantastic and performs better than ever. I have no complaints so far regarding visuals or performance. Nothing seemed problematic regarding “pop-in” behavior at all (which is to say, I see no “pop-in” effect at all when panning the cockpit camera or external camera). Running at 3440x1440 at Ultra.

(I do have complaints about the update process and compatibility with third-party add-ons distributed through the Marketplace.)

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Here’s a video I took heading into Chicago from Midway. It’s not horrible, but it is pretty immersion breaking. I hope they give those folks with higher end systems the ability to tweak this via a slider.

Edit: Above taken using TrackIR

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I have to pan a lot faster than I normally do to reproduce any such effect, and it seems pretty minor to me. I wouldn’t complain about it personally, given the HUGE performance improvements. shrug

I’ll test it in VR, see how it feels…

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Yeah, panning in external view is fine, the sim can keep up, and that’s nice because that’s how I do a lot of my sight seeing around cities. But I fly from A to B using TrackIR (which is what the video was taken using) and there I’m constantly looking around pretty quickly.

Like I said it’s not horrible, but im for those of us with system performance to spare, it’d be nice for Asobo to give us the option to keep more stuff in memory e.g.

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When I was young, flight simulators didn’t have textures much less photogrammetry cities. I’d much prefer the higher frame rate when it comes to “immersion”. :slight_smile:

I flew into SLC tonight (daylight in sim) and noticed the terminal was missing it’s walls and the mountains had a low LOD at a somewhat close range. I noticed the culling issue in Chicago earlier today. I can live with it but, kinda annoying on the realism side. I vote for a slider!

Atop those LOD issues, I had a pair of long freezes (no CTDs), ATC always thought I was off my assigned altitude and winds aloft were always tame. I noticed those high OAT’s too!

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Ok I tested in VR (Valve Index) and I can see the effect when looking back and forth quickly but it doesn’t bother me in any way whatsoever. Not at all an “immersion killer” to me, any more than a mouse cursor or an ATC dialog window. :slight_smile:

Video capture (may take a bit to fully render the 4K recording)

The performance improvements in SU5 are outstanding, but I agree that this LOD pop-in behavior will not work long-term. Especially for TrackIR/VR users where camera movements are common, the pop-ins are so obvious whenever you look left and right.

I hope they add a slider to prevent this from happening. I would gladly have less FPS (as long as no stutters) if I get to keep the terrain looking the same and avoiding pop-ins as I look around.

Update: I noticed that the pop-ins are more obvious for vegetation. If you want to try it out, try going up to around 3000ft in an area with lots of trees and start looking left and right. This will make the pop-ins more abrupt. With buildings there are still pop-ins, but it is not obvious and those I can live with.

I wonder if simply increasing the Terrain LOD will be enough to avoid the pop-ins? I have mine set to 100 at the moment. I’ll try later today to increase it to 200 if I get some time, but if anyone has tried already, I’d be happy to hear how it looks for you.

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OK, it looks like I was wrong and it was a temporary, first-load thing for me. When I first went into the game, the BING data was drawing a few miles out. About maybe 1 third the distance that I would consider OK. I did wait awhile to see if it would keep drawing into the distance but it didn’t.

But, I’ve just gone in again and this time (where BING was enabled when I first started the flight), and it looks great again. So I’m not sure what the initial issue was but it looks like it was transient so that is OK.

The building in the distance drawing seemed better too. Though I didn’t do the same flight path as the first flight. Hopefully that was transient too.

One thing I did change was my detail and terrain sliders from 100 to 150.

The clouds don’t seem as good, especially in HDR where they are getting way over saturated in one direction. But maybe I’m feeling picky and it may not be that different. It is interesting to see them slowly morph as they move though. I’m not sure I noticed that before.

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I throw something in I was thinking of when I stumbled across this popping in, let me know what you think, maybe you could even run some tests:

Some of you will remember that in the old ESP based sims it was basically possible to overload your rig (more specifically your CPU…) without (!!) totally ruining your FPS, it became only visible when actually flying around. The most prominent symptom was blurry ground textures because the rig could not keep up with scenery loading. FPS remained almost unaffected.

NOW: could it not be that we have a comparable situation here in MSFS after SU5? People now increasing their LOD via UserOpt.cfg because their FPS counter still reads almost the same numbers probably suffer from this LOD pop-in simply because they overload their rigs without losing FPS?

So, for those having excessive LOD pop-in I strongly suggest to once run the sim without increased settings and compare.

Yes this large drop-off in FPS when panning is more problematic the higher the LOD slider. Set it to 100 and the FPS drop is not very noticeable (maybe why many people are not noticing this). Set it to 200 or 400 in the user.cfg and the FPS drop massively when panning. Seems the problem is affecting users with high end systems who were already running LOD 200+ pre-update.

I’m finding the free-look mouse has become almost unusable now. Try looking down at the centre pedestal then looking up at the overhead and there is a huge pause when passing through the horizon as the scenery is loaded. It seems the scenery culling is evening happening when looking up at the overhead. Again, set the LOD slider to 100 or less and the effect is less pronounced, but why should we have to set LOD to 100 when pre-update LOD 200 was working fine.

Just wish they could scale the game to suit high end PC systems by allowing more of the scenery to sit on the VRAM. I’m using a 3090 and currently only seeing 6GB or so utilised. Surely if this is a 10+ year project they will need to revisit this scenery culling in the future.

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I am running it now and pop-in is greatly improved, looks like server traffic from the update was a factor

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