Gradual vs Quantized LOD

[Payt691]

I’ve been wondering about the possibility of MSFS ever solving the problem with the LOD (Level OF Detail). As it is now it increases in steps, which constantly causes jarring jumps in the scenery as you fly along.

The best solution visually would be to have maximum detail everywhere, so you don’t get any jumps. This is what Xplane used to be like, until a few years ago they adden an extra layer for really far away scenery, which used a really low poly count and a basic texture of the landscape mapped onto it. Everything past this level was just one LOD, so you didn’t get any further jumps in LOD as things got closer. The drawback is that at close range thing remain a bit low poly and crude looking.

MSFS has always used several steps of LOD. This allows for more detail in the foreground, where you need it the most, and less in the background, where you can get by with less of it, so you’re distributing the amoutn of polygons between close and distant scenery, and the clostest stuff gets the highest amount of polygons for max detail.

This has always caused some jarring jumps in LOD detail. As you get closer to a mountain, you can see it progress through sevral stages of LOD.

In my mind the solution would be to have a GRADUAL increase of LOD. As things get closer, more and more ‘nodes’ get added to the mesh, so you don;t get sudden jumps in the LOD.

The fun thing is that you could plot this increase to several lines. If you want to keep the general amount of nodes/polygons low you could have an exponential line so that only the closest scenery gets a lot of detail, while a more linear type of line would provide more detail in the background as well, but also uses more polygons and hence requires more GPU power.

Anyway I think this would allow for a much smoother experience in MSFS. of course the problem may be that it’s based on the ancient ESP engine, and rewriting it would be a bit of a task. Still I think it’d be worth the effortm because the jumps in scenery are still one of the most obnoxious idiocyncracies of MSFS. let’s hope the Asobo team agrees and maybe, perhaps maybe we’ll see something like this in 2024

Feel free to voice your opinion on this

[BeardyBrun]

Don’t think that sounds like a practical prospect. Not sure of the specifics of MSFS but typically, LoDs (whether terrain or other objects) are discrete meshes which are loaded (and streamed in this case) independently depending on proximity to the player camera. They’re not single models which ‘evolve’ to different amounts of detail.

I don’t think there’s a technologically feasible way to ‘gradually add nodes’ (I think you mean vertices) to a mesh as it gets closer. 3D geometry just doesn’t work like that.

Unreal’s Nantie technology is an alternative to LoDs, but that still requires the highest resolution meshes to be on the local computer. Fine if it’s an installed game, but more problematic if the data has to be streamed.

The proper use of LoDs in any context is that the change between detail levels should happen at a range where it’s not visible, or at least not jarringly so as in MSFS.

[PacyFire]

A fading system is easier to implement and would dramatically reduce the jarring jumps as well. You can vote here:

Implement some type of LOD fading system to help reduce terrain and object pop-in

Sometimes I’m flying around terrain or points of interest such as the Rock of Gibraltar but the object detail is bad until I approach very close to the object. The same thing happens with objects at airports such as taxiway signs, other planes on the ground, baggage carts, etc. Some other games use an object fade-in approach to reduce the “popping” at different LOD levels. Please implement something like that to improve graphics quality and realism. Thanks!

[DensestSnail693]

Improvements are aways worth consideration but I think poor and inadequate data will always be the real issue and unfortunately there’s ony so much can be done to negate this. Except the procurement of better data which will happen as it becomes available (with some reworking) as part of the natural process.

[PacyFire]

@DensestSnail693

poor and inadequate data will always be the real issue and unfortunately there’s ony so much can be done to negate this.

Yes, but I don’t think that is the core issue here. There are only a few levels of LoD and the delta between them is jarring so a smoothing transition effect is needed to alleviate it.

[DensestSnail693]

There’s something like 30 levels of LOD maybe more

[PacyFire]

Okay, let’s assume you are right.
There is only one level of source data at the highest detail available and all the other LoDs are derived from it at successively lower number of polygons. If 30 levels are jarring, do you really think 60 levels are going to fix it? No, transitioning between levels is key.

[DensestSnail693]

And thats why we have AA etc.

[PacyFire]

AA (anti-aliasing) does nothing to smoothen the transition from one LoD (set of mesh vertices) to the next. It only smoothens pixel transitions between frames.

[DensestSnail693]

I’m not going to argue this but in a limited way it does over a small sample size.

[PacyFire]

Maybe we are just misunderstanding each other?

To me the topic of this thread is the jarring replacement of polygons representing one LoD with the set of polygons that represent the next higher LoD. The affected polygons take up screen space from about 20 pixels to large sections of the screen (i.e. alp mountains still jumping LoD when they are close to you).

Anti-aliasing, by definition, deals with sub-pixel issues and as such has no impact on the topic of this thread.

[DensestSnail693]

@PacyFire

(i.e. alp mountains still jumping LoD when they are close to you)

Please refer to my earlier post about bad data which incidently includes mesh data specific to this problem.

And I know how AA works I was editing animated gifs to not look like gifs when transparency was but just one colour in the palette … by hand no less it was that long ago