Slider to adjust/disable the scenery culling (reduce panning pop-in and stutters)

Hi all,

I’ve spent some time the past few weeks gathering some details to share on this new feature and how it works. As you know there is a new setting coming on Tuesday with World Update 6 called “Offscreen terrain pre-caching” and will be available on PC. This option defines what level of detail your offscreen terrain will stream into memory.

The definition of “Off screen terrain” is anything not currently visible behind the user.

First question I saw was, “If set to Ultra, all the offscreen terrain will be cached at full quality - does this include buildings and trees in addition to ground terrain?” Yes, this includes not only terrain but buildings, trees, photogrammetry, textures, and everything else in the world.

It will have four settings:

  • Low - This setting will improve performance but a lot of terrain data is streamed at a lower quality behind the user, while FPS drops may increase when turning your head.
  • Medium - This is what you currently have right now in the current build. The terrain behind the user is streamed at a lower quality and reduces the impact on memory and FPS, but when turning your head will need to stream the terrain.
  • High - High will be an intermediate state between Medium and Ultra
  • Ultra - This is will have no offscreen caching at all, and everything will be maxed out based on your graphics setting. The quality in front of the user is the same as from behind the user, so nothing needs to be loaded. This could come with some FPS drops when turning the head, but would result in higher FPS and lower memory usage when looking forward and not turning your head quickly.

Hope this answered some questions, and I am working on gathering information like this to help out with new features in future updates as well.


Fantastic information. Thanks for the very detailed information. Much appreciated.

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Thanks a lot for the detailed explanation, it is really appreciated! I would like to point out a couple of things:

  1. I think it would be better if the setting were called “Offscreen Terrain Caching”, rather than “Pre-Caching”. This wording suggests that terrain will be pre-loaded before the flight begins or something similar, which could cause some confusion regarding what it’s supposed to do. It might be too late now since the build is probably very close to completion, but hopefully the developers will consider renaming it in the future.

  2. I think the explanation of the Ultra setting is incorrect in a couple of areas. “no offscreen caching at all” probably means “no offscreen culling at all”, since the offscreen scenery will remain in memory. Also “This could come with some FPS drops when turning the head, but would result in higher FPS and lower memory usage when looking forward and not turning your head quickly” is probably more appropriate for the lower settings, because having all the scenery remain in memory means higher memory usage of course, and there shouldn’t be stutters when panning the camera (but rather the frame rate will remain consistent no matter the camera’s position).


Thanks for pointing that out! I don’t know what the final setting title is, so I can’t comment on if it’s “Offscreen Terrain Caching” or “Precaching” or perhaps a variation of that.

And on your second point, you’re correct there too. There would the a chance for FPS drops turning your head on lower settings.


So even in Ultra, we will still have the fps drop while turning quickly. That partially solves the problem.

Thanks Jummivana !

Thank you for coming forward with these great details, this is much appreciated.

I’m certain this will help reducing a lot of the annoyances with terrain “reloading” but this raises other questions: what is the definition of “not currently visible behind the user”?

I know this sounds like a silly question but I wouldn’t ask if this wasn’t a little bit more complex than what it looks like:

This question probably concerns VR users more than 3D users because the former are using all sorts of headsets with all sorts of FOV and the current game code is not working well with these differences in FOV.

There are topics about the Pimax headsets where you can read this:

I’m also reporting bugs with discrepancies between both eyes because of what seems to be the viewdir vector Maths (from the look of it - no pun intended):

NB: the “viewdir” bug is not directly related to the question of “pre-loading what’s out of view” but there remains problems in VR with discrepancies between both eyes rendering and I hope this new WU6 option won’t add one more in VR.

So to the question

  • What defines “what is behind or what is not visible” when in VR, is supposed to be what is outside the FOV. Does it mean the addition of this setting is also telling all the reported VR bugs related to FOV have been corrected as well?

  • Since at some point in the code logic there must be some Maths telling it is in front (within FOV) and it is behind (outside FOV), why not also adding at least for VR users a setting to set the value of the FOV determining what is within and inside, so that it kills 2 birds with one stone: supporting the new feature (late-load/early-load of assets) AND supporting wide/.narrow FOV headsets properly?*

*of course, offering an “angle culling setting” instead, would mean user’s could get the equivalent of the upcoming setting too:

  • Setting the culling to the headset FOV would effectively mean “like SU5 i.e. Medium with the new setting”
  • Setting the culling angle to 180deg would effectively be equivalent to “the new Ultra setting”

In addition, an “angle culling setting” is high in demand already:
Support for Wide FOV VR headsets (removing Frustum Culling issue)- - Virtual Reality (VR) / VR Wishlist - Microsoft Flight Simulator Forums


Hello, Jummivana,
Still, it would be great if such information appeared either in the developers’ diaries or in the News section, so that it would not be necessary to search for such useful messages on the forum. And I also have this question: I am sure that there is an average data on the amount of memory that is recommended for the new High \ Ultra settings. Can you find out what these values ​​are?


Will there also some more Options and ooptimization for Xbox Simmer ?

So was Pre-SU5 HIGH or ULTRA? If SU5 is MEDIUM as stated, I’m leaning towards it being ULTRA as I (for one) never had that pop-in prior to SU5.


No offence but this was a completely confusing and contradictory post.


Interesting. I had found that the current “Medium” setting I guess has even worse FPS drops than before when turning the camera. I would imagine UItra should has less of an FPS drop since the objects are already loaded into memory.

This sounds fantastic, thanks you so much!

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I would wager a guess there was only one setting and it was probably a total mix of every setting the new setting will have. After the optimization, which probably only got budgeted for because of Xbox, there was probably a much more straight forward way to manage how much stuff is being loaded on different hardware.

What could go wrong??? I want to
Believe :innocent::grimacing::face_with_raised_eyebrow::cry:

I’m still not getting the update and it will probably take a long while, so I would love to hear some opinions on the new graphics setting from those who have tried it.

Warning: The setting not appearing in the VR menu is a known issue. Please do not vote yet if you’re using VR. Vote for “VR/TrackIR user” if you’re using TrackIR for now. The poll cannot be edited sadly.

Are you satisfied with the functionality of the “Off Screen Terrain Pre-Caching” setting?
  • Yes (2D user)
  • Yes (VR/TrackIR user)
  • No (2D user)
  • No (VR/TrackIR user)

0 voters

Currently investigating the new option not showing up in VR.


Thanks Jayne! :blush:

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From the testing I’ve done, at different Terrain LOD settings and both over photogrammetry and mountains, the setting seems to work perfectly. The pop-in and stutters when panning or switching camera views is totally gone, and performance is still great!

Quite unfortunate that VR still doesn’t have the option, hopefully it can arrive with a quick hotfix. Thank you Jayne for immediately looking into this.

For now, please do not vote in the poll if you’re a VR user as I’m looking to see whether the slider itself is effective for everyone. But you should do so if you’re using TrackIR.

  1. I never had a problem with Culling while panning the camera.
    I don’t know if \it was fixed or not.

  2. I had previously changed the UserCfg.opt file as follows:
    Preset Custom
    ObjectsLoD = 9
    TerrainLoD = 9
    File set to read Only

  3. Still need to set this after this update.
    This was not affected by this update.

Very pleased to have the building+tree pop in on head fixed, I am loving my VR flying again :heart_eyes: I would say I can still see some very rapid (near instantaneous pop in) on rapid head move, but none in more normal operation. Thank you !

Also I still have sometimes ground texture checkerboarding/frustrum culling on head move mainly at airports, so it seems not all ground textures are cached (lots of RAM+VRAM available):