FSX default terrain vs. downloads

[meshman 109]

Except for occasional artifacting at 1 or 2, and sometimes even at 5. Read my posts above for details. Also, there's plenty of evidence that in some areas the default FSX terrain is 1 or 2.

 

Edit: I was surprised flying down the Orinoco River in South America to see so many bands of rock going across the river. This was at 5. I'm guessing it's because the river has to change elevations. These are thankfully rare.

 

I recommend 5. If the terrain mesh allows it, you'll see 5. If you set 1 or 2, you'll eventually see problems.

 

Hook

 

Only with the Acceleration package did Microsoft add 2.38m mesh and that is only in a couple, three spots. Mount St Helens being the most familiar name. Even these small areas were compressed down more than what others may use when making mesh.

 

Hook, you're seeing rocks in the water because you are using the default Terrain.cfg file. Since water carries elevation and there is a certain slope % between data points FSX slaps a hillside texture onto those areas. Check out the Thames in London, you'll see a lot of rock areas with the default Terrain.cfg file. There is a modified Terrain.cfg file by Luis Feliz-Tirado and Dick Ludowise in the library here. Highly recommended for everyone to use the modified file, as it fixes a couple of problems within FSX and brings forward some stuff from FS9 terrain to work in FSX.

 

FWIW, there is a large % of the world in FSX that has 608m mesh. Yes, six hundred meters between data points. There are alternatives to this mesh meltdown, available in free and pay ware. Some good, some not so good. I don't recommend to users to set the mesh slider any greater than what they have installed on their computer. I've had instances where even with very high res mesh, going further right on the slider can introduce small mesh anomalies.

[LHookins 3,103]

Only with the Acceleration package did Microsoft add 2.38m mesh

 

What's the lowest mesh in SP2?

 

There is a modified Terrain.cfg file by Luis Feliz-Tirado and Dick Ludowise in the library here.

 

I'll check that out, thanks!

 

I've had instances where even with very high res mesh, going further right on the slider can introduce small mesh anomalies.

 

Exactly.

 

Hook

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There is no negative effect to setting it to 5 when you are in a 38 area.

 

Are you sure? Read what Phil Taylor from ACES Studio wrote:

"30m source data and a slider set to 1m is causing a lot of interpolation code to run on the BGL data as well as a tessellation to triangles for the hw rendering."

Source: http://blogs.msdn.com/b/ptaylor/archive/2007/10/28/game-engine-design-design-goals-and-design-influences.aspx

[LHookins 3,103]

Are you sure? Read what Phil Taylor from ACES Studio wrote:

"30m source data and a slider set to 1m is causing a lot of interpolation code to run on the BGL data as well as a tessellation to triangles for the hw rendering."

 

He said 5 meters. That quote says 1 meter. I think most people know that 1 meter resolution causes problems, as mentioned in several posts above.

 

Hook

[vgbaron 3,606]

Also, that blog was written in 2007 and all it says is that it causes a lot of code to be executed. With today's hardware, that particular issue is not as important although, as Hook said, at 1M there are known issues.

 

Vic

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He said 5 meters. That quote says 1 meter.

 

Don't you understand about what is this info? One meter is just example. It is about unnecessary interpolation and tesselation made when is used lower (closer to 1m) setting than is resolution in source data. In default FSX most of USA has 38m mesh and every lower setting (19, 10, 5, 2, 1) than 38m causes unnecessary workload for both CPU and GPU. Lower the settings (closer to 1m), more unnecesary computational work.

[LHookins 3,103]

Don't you understand about what is this info? One meter is just example.

 

No. All I know is, I've been using 5 meters for the last year, about 450 hours flight time, without problems. I tried 1 and 2 meters and saw various artifacts, almost no artifacts appear at 5 meters, certainly within acceptable limits. I fly low and slow, so I see a lot of terrain.

 

Hook

 

It is about unnecessary interpolation and tesselation made when is used lower (closer to 1m) setting than is resolution in source data.

 

This "unnecessary" interpolation does improve the looks of the terrain. At least that explains why at 1 meter the stream actually cuts through the ridge in my post above.

 

Hook

[meshman 109]

What's the lowest mesh in SP2?

 

38m. Highly compressed 38m.

 

Also on the modified Terrain.cfg file, there is one entry that needs a value corrected. I'll have to track that down, as I didn't make the correction when I installed it earlier this year.

[ad_verbum 0]

This "unnecessary" interpolation does improve the looks of the terrain.

 

You are magician ;-) making terrain improvements without source data. if you are using mesh with 38m resolution that means two closest vertices of terrain with elevation data are spaced from each other by 38m. There isn't any data between these two points.

Adding some more points between by making interpolation you should get only straight line with some more points on that line, so what sense is to do that?

 

 

Also, that blog was written in 2007

 

The same I may say about FSX code.

 

 

all it says is that it causes a lot of code to be executed. With today's hardware, that particular issue is not as important

 

Are you sure that FSX is able to take advantages of hardware tessellation in PolyMorph Engine on Fermi/Kepler GPU?

I don't think so as hardware tessellation is avaliable since DirectX 11.

It is still a lot of work to be done for CPU in FSX world and if I remember correctly in any demanding conditions (high resolution photosceneries, high res. mesh - some european sceneries comes with 5m meshes that is huge amount of data, large and detalied airports) bottleneck is CPU. So that isn't wise idea wasting computational power of CPU for making "empty" tessellation without proper source data.

 

If you are familiar with FSX SDK you may easy check what is influence of exaggerated mesh resolution setting on CPU workload.

 

Just make some empty (gray) ground fotoscenery tiles covering area about 30 x 30 km and test such scenery with default USA mesh (38m) - notice workload of T&t loaders (core1, core2, core3). Next repeat the same with 38m mesh and lower mesh resolution settings (for example 10m and 2m) - again notice workload of T&t loaders. Then compare results. I did a lot of such tests with default USA mesh and 10m FSGenesis mesh around KBIH airport.

 

Conclusions are simple:

(1) default mesh (38m) and mesh resolution settings: 38m - are causing low workload

(2) default mesh (38m) and mesh resolution settings: 5m - are causing much higher workload than in case (1), terrain looks exactly the same as in case (1)

(3) high res. mesh (10m) and mesh resolution settings: 10m are causing middle workload

(4) high res. mesh (10m) and mesh resolution settings: 2m are causing much higher workload than in case (3), terrain looks exactly the same as in case (3)

 

Why fotoscenery? Answer is simple, in such case only data will be mesh and very simple texture (our gray one) - no vector objects, no autogen - just to measure mesh influence on CPU workload. Why gray tiles? Because of very low data level in .bgl files and excelent view of terrain relief.

[meshman 109]

I'll check that out, thanks!

 

If you do decide to use the modified Terrain.cfg file (highly recommended), open it with Notepad or similar and find entry #266: Airport Backgrounds (FSX) - Flatten Change the Render Priority from 20000 to 200000 (20K to 200K), save and exit. Gives the airport flatten greater priority over other scenery types, there was a typo on the release.

[LHookins 3,103]

Notepad or similar and find entry #266: Airport Backgrounds (FSX) - Flatten Change the Render Priority from 20000 to 200000 (20K to 200K), save and exit.

 

Line 4246. Lots and lots of changes in there. This will be interesting next time I fly. Thanks.

 

Hook

[Dreamflight767 312]

So, a settings questions. If I'm using FS Global 2010. What should I have my settings at?

[eghansen 1]

I purchased FSGenesis mesh for the whole world about four years ago. I don't know what the density of the mesh is in meters, but the file sizes are much larger than the FSX default. This particularly truie in areas outside of US, Europe and Japan.

 

Example:

 

dem0801.bgl 4039 KB

FSXdem_0801.bgl 104436 KB

 

dem0802.bgl 12551 KB

FSGdem_0802.bgl 304852 KB

 

dem0803.bgl 862 KB

FSGdem_0803.bgl 48619 KB

 

I certainly notice the difference between default and FSGenesis!

[simmerhead 885]

 

 

If you do decide to use the modified Terrain.cfg file (highly recommended), open it with Notepad or similar and find entry #266: Airport Backgrounds (FSX) - Flatten Change the Render Priority from 20000 to 200000 (20K to 200K), save and exit. Gives the airport flatten greater priority over other scenery types, there was a typo on the release.

 

Thanks a lot!

[ad_verbum 0]

So, a settings questions. If I'm using FS Global 2010. What should I have my settings at?

 

I purchased FSGenesis mesh for the whole world about four years ago. I don't know what the density of the mesh is in meters, but the file sizes are much larger than the FSX default. This particularly truie in areas outside of US, Europe and Japan.

 

1. Resolution of FSX default mesh:

USA - 38m, it is resampled resolution* (source: ?, source resolution: ?)

Western Europe, Mexico, Canada - 76m, it is resampled resolution* (source: SRTM, source resolution: 90m)

Rest of world - 304m or 608m

Very few small areas may have better resolution that mentioned above. There was the list of these places at FS Insider (if I remember correctly), but MS removed it as many other resources of FS Insider after closing ACES Studio. Maybe somebody have it and would like to remaind?

 

2. Resolution of freeware mesh for FSX (FSX Freeware Global Terrain Mesh Project):

USA - FSX resolution 10m (source: NED, source resolution: may vary but mainly 10m)

Canada (Quebec) - FSX resolution 38m, it is resampled resolution* (source: SRTM or CDED, source resolution: 20m or 90m)

Canada (West) - FSX resolution 19m (source: CDED, source resolution: ~20m or 90m depending source 1:50K CDED or 1:250K CDED)

Western Europe - FSX resolution 38m, it is resampled resolution* (source: SRTM, source resolution: 90m)

Australia - FSX resolution 76m, it is resampled resolution* (source: SRTM, source resolution: 90m)

New Zeland - FSX resolution 76m, it is resampled resolution* (source: SRTM, source resolution: 90m)

 

3. Resolution of commercial meshes for FSX:

FSGenesis:

USA - FSX resolution 10m, (source: NED, source resolution: may vary but mainly 10m)

Canada - FSX resolution 19m (source: CDED, source resolution: ~20m if 1:50K CDED was used)

Western Europe - FSX resolution 10m (source: NEXT Map, source resolution: 5m or better)

Northern Andes - FSX resolution 19m, it is resampled resolution* (source: NEXT Map 30, source resolution: 30m, compilation of SRTM 90m and ASTER 30m data)

Rest of world - possibly next areas with NEXT Map 30 from FSGenesis.

Notice - for now NEXT Map 30 is the best avaliable source with world wide coverage.

 

FS Global Ultimate:

The producer do not specify the grid resolution for some of geographical areas. Only given are: USA resolution (10m), part of Canada (19m) and Mexico (38m). We can suppose that if the publisher does not want to brag, the source material for the rest of areas was the SRTM 90m.

 

FranceVFR:

Western Europe - FSX resolution 5m (source: NEXT Map, source resolution: 5m or better)

 

Some European sceneries (Playsimspublishing - HorizonVFR, FranceVFR) come with included very high resolution mesh (5m or 10m).

 

* Important notice about resampling:

In most cases source resolutions: 90m (SRTM), 30m (ASTER, NEXT Map 30) doesn't match to FSX's mesh LOD steps (19m, 38m, 76m, 152m) and must be resampled to one of two adjacent mesh LOD levels. For example world wide SRTM data with resolution 90m is resampled to 76m mesh, sometimes called 76m SRTM mesh, but that doesn't improve level of detail (terrain relief) - it depends only on source resolution.