LOD of Aircraft

The LOD (level of detail) helps to save performance by decreasing the mesh complexity of objects that are further away. Usually this is a good thing, but I think DCS should allow aircraft to have much more level of detail than less important objects like trees or buildings, because it is very important to spot aircraft in a distance without having to zoom in.

After flying hundreds of hours in DCS I often observed how the LOD decreases the visibility of aircraft too much. You can see the effect of LOD by zooming in and out. I found out that there are certain zoom levels, where the LOD significantly increases, if your zoom passes that threshold. In that case the shape of an aircraft from a few miles gets significantly much thicker and you can see it more easily, but when you zoom out just a little bit below that threshold its shape gets thinner and much less visible. So that is a proof for me, that the LOD worsens aircraft visibility too much, even though in my graphics setting the visibility distance is maxed out.

In my opinion ED should apply extra rules for aircraft (and helos) such that their LOD decreases much slower than other objects with increasing distance.

I find it way too high ..at least in VR looking at parked hornets. The object count sky rockets and fps plummet even though the image is pretty blurry in VR. Cam we reduce the LODs manually for the hornet?

VR blurriness is a hardware issue, but physically, it displays a lot of objects, take it as a side note. And the Hornet is the worst example you could have choose because it's LOD is still pretty much WIP from what I know (not optimized yet), that's why it tanks FPS really hard.

We can't do anything with LODs, as it would have to be done with original 3d models in 3ds max (or any other 3d modeling program that supports .edm plugin).

I agree with pretty much everything that OP said, we need better LODs.

Hi, I'm from the future. Meanwhile there are 3 modules launched F-16, Hind and Apache. They have no LOD. The instant fly mission free flight of Syria with Apache starts with 19 million triangles in VR. 

On 7/14/2019 at 11:54 AM, Tiramisu said:

The LOD (level of detail) helps to save performance by decreasing the mesh complexity of objects that are further away. Usually this is a good thing, but I think DCS should allow aircraft to have much more level of detail than less important objects like trees or buildings, because it is very important to spot aircraft in a distance without having to zoom in.

After flying hundreds of hours in DCS I often observed how the LOD decreases the visibility of aircraft too much. You can see the effect of LOD by zooming in and out. I found out that there are certain zoom levels, where the LOD significantly increases, if your zoom passes that threshold. In that case the shape of an aircraft from a few miles gets significantly much thicker and you can see it more easily, but when you zoom out just a little bit below that threshold its shape gets thinner and much less visible. So that is a proof for me, that the LOD worsens aircraft visibility too much, even though in my graphics setting the visibility distance is maxed out.

 

In my opinion ED should apply extra rules for aircraft (and helos) such that their LOD decreases much slower than other objects with increasing distance.

 

Have you tried using the "Dot Neutral" setting under "Markers"?

It sure helps my 70+ year old eyes.  

On 7/14/2019 at 1:54 PM, Tiramisu said:

The LOD (level of detail) helps to save performance by decreasing the mesh complexity of objects that are further away.

  Correct

On 7/14/2019 at 1:54 PM, Tiramisu said:

Usually this is a good thing

  It's not ''usually a good thing''. It's a necessity.

On 7/14/2019 at 1:54 PM, Tiramisu said:

but I think DCS should allow aircraft to have much more level of detail than less important objects like trees or buildings, because it is very important to spot aircraft in a distance without having to zoom in.

  You could have 2,000,000 polys or a 6 sided cube, that doesn't have anything to do with its visibility.

On 7/14/2019 at 1:54 PM, Tiramisu said:

After flying hundreds of hours in DCS I often observed how the LOD decreases the visibility of aircraft too much.

  That's because some of them are poorly done or outright missing (the MiG-21 used to literally vanish at certain points because they forgot to assign a model to some ranges). It's not an issue with LoDs in general.

On 7/14/2019 at 1:54 PM, Tiramisu said:

You can see the effect of LOD by zooming in and out.

  That is indeed how they work, yes.

On 7/14/2019 at 1:54 PM, Tiramisu said:

I found out that there are certain zoom levels, where the LOD significantly increases, if your zoom passes that threshold. In that case the shape of an aircraft from a few miles gets significantly much thicker and you can see it more easily, but when you zoom out just a little bit below that threshold its shape gets thinner and much less visible.

  This is a symptom of them being poorly done, rather.

On 7/14/2019 at 1:54 PM, Tiramisu said:

In my opinion ED should apply extra rules for aircraft (and helos) such that their LOD decreases much slower than other objects with increasing distance.

  It's not the number of polys. It's the shape, size, and overall appearance. A LoD is literally a 3d model, usually algorithmically reduced polycount that switches on the fly as you get progressively closer. You don't need 2,000,000 polys to resemble an F-16 or to be visible. The overall issue comes down to color and contrast usually, as well as the overall characteristics of the 3d model they're using. Aircraft themselves are usually technically visible (as far as rendering) but they don't contrast very well or sometimes artifact/glitch (I observed a F-18 ''sparkling'' in a bizarre fashion that made it extremely hard to track but that was likely related to my headset).

Regardless, it's not the LoDs or polycount that are the issue. It's literally everything else.

Note that these days, polygons are not a major FPS killer, as long as you don't go totally overboard with them. Textures are, and the big deal with LODs is that they can use vastly reduced texture size, with no or very few additional maps. They also don't have most animations and have simplified lighting, the latter of which is another way to save big on performance. A well-done LOD is not noticeable visually, the mesh doesn't actually need to look like a Flanker 2.0 model for this technique to work.

That said, many LODs in DCS are not well done. 

On 4/9/2022 at 10:44 PM, Dragon1-1 said:

polygons are not a major FPS killer, as long as you don't go totally overboard with them

Quick start mission of Apache in Syria starts with 19million triangles. I believe this is going overboard if you are not using Unreal Engine 5. 

every apache is around 5 million triangles (hornet or A-10 is less than 600,000 in comparison and they do not look inferior in detail and they all have lod's apache does not) so you and your wingman and 2 other parked apaches brings you the whopping 19M triangles. 

F-16 is arounn 1M triangles without Lod. So when you are flying in free flight in syria for example. You extend from your wingmen until it becomes a dot than you look around you render around 1.6M triangles and when you turn your head to the direction of your wingmen so that the small dot gets redered your triangel count jups to 2.7M. As you said they are being rendered with full effects on and it hurts it. 

It is not only playable aircraft there are also some ground AI assets which have no LOD's and being rendered at full glory with unnecessary thousands of triangles which you actually never see. 

47 minutes ago, Rapierarch said:

Quick start mission of Apache in Syria starts with 19million triangles. I believe this is going overboard if you are not using Unreal Engine 5. 

every apache is around 5 million triangles (hornet or A-10 is less than 600,000 in comparison and they do not look inferior in detail and they all have lod's apache does not) so you and your wingman and 2 other parked apaches brings you the whopping 19M triangles. 

F-16 is arounn 1M triangles without Lod. So when you are flying in free flight in syria for example. You extend from your wingmen until it becomes a dot than you look around you render around 1.6M triangles and when you turn your head to the direction of your wingmen so that the small dot gets redered your triangel count jups to 2.7M. As you said they are being rendered with full effects on and it hurts it. 

It is not only playable aircraft there are also some ground AI assets which have no LOD's and being rendered at full glory with unnecessary thousands of triangles which you actually never see. 

and you know all of this because??????

video diagnostics 3d model information egg. in 3d model viewer, 3d model Lod0 file size etc..

19M tris isn't what's bogging things down. Modern GPUs are perfectly capable of displaying that many, although not effortlessly. The biggest FPS killers on the GPU side are 4K textures clogging up VRAM, volumetrics and advanced lighting. Whether you use UE5 or DCS doesn't really matter because it all goes through DirectX, anyway.

We do need LODs, but the primary reason is to avoid rendering all those 4K textures with their normals, speculars and whatever (too often it's all in 4K, regardless of actual need), at ranges where a single 512x512 map would suffice. Reducing the tris count would be useful as well, but GPUs are good at rendering tris. It's been ages since polycount was the primary concern.

On 4/18/2022 at 2:41 AM, rayrayblues said:

and you know all of this because??????

 Because we have access to the source files and can pop up the ingame fps display which displays it all in red text before your very eyes?

Well it doesnt make sense to start making Lower LODs Models until the Main Model is Finalized...

The Apaches is 600,128 Triangles, and newer models likely wont have separate EDMs for lower LODs as you can put them all in a Single LOD and toggle between them with view distance.

As for Textures, that's what MipMaps are for.

On 7/30/2022 at 6:40 PM, SkateZilla said:

Well it doesnt make sense to start making Lower LODs Models until the Main Model is Finalized...

  Strictly speaking, by the time you're looking at various LOD levels it doesn't really matter if the primary one is ''finalised'' or not. From very far away, you could drop the old AI model and never know the difference from a practical standpoint. They're dropping details rapidly as you move away in the first place, so whether the chaingun animations exist, the nosepod swivels, the wheels are exactly round, or the text near the tail rotor is upside down, doesn't really matter.

Well - I don't have that much experience. All I can say is: Textured polygons in large masses are still a problem for the CPU/GPU and its memory. Mipmapping makes for faster rendering- but it has to be completely loaded into memory first. Because it is still one Texture.
You notice it when you fly online to an aircraft carrier and another aircraft spawns on the deck. You can't really see it yet, but you notice a lot of lags and stutters. 
The Marianas generally have too many polygons and the players rightly complain about heavy judder, stuttering and interruptions. 
Because ground objects also need very well-made LODs. So yes - a too high polygon load still has glorifying effects! 

But as I said: I don't have much experience with it. I just hope that it will get better in the future. 

Cheers

TOM

the lag is the DX11 API bottleneck trying to process all the draw calls

7 hours ago, SkateZilla said:

the lag is the DX11 API bottleneck trying to process all the draw calls

  The gnomes coding Vulkan... you're feeding them too much. That's the problem. Reduce them to quarter rations and increase whippings until FPS improves.