Can Someone Explain "Mesh" to Me?

What are Mesh add-ons supposed to do? I note that an Orbx promo for their upcoming Alaska Mesh says it changes no default mesh, and alters no files, with minimal performance effect. Okay . . . .

 

I recently added freeware mesh for Italy, and flew around a bit. Italy looks fine, but I thought it looked pretty good before. Of course, once you install, you can't easily compare "before" and "after." I did, however, compare a recent screenshot of the Vesuvio summit with the default, and saw no difference.

Mesh defines the shape of the terrain, including hills, valleys, canyons, large boulders, ditches, escarpments, etc. Visualize in the real world laying a giant net over the land (empty of buildings and such, of course), then shrinking that into a file that can be put into the sim to replicate that shape.

 

That net, in the sim, will have less detail than in the real world, so the difference between the default mesh in your sim and an add-on is likely to be the level of detail it shows. Sometimes you'll have to look very close at ridges on mountains, passes between mountain peaks, even just ditches or ravines, in order to notice the differences. Often the difference is small, other times a lot, depending on what sim, what add-on, what levels you choose in the sim settings, and other factors.

 

While I don't have the 2020 sim, in FSX and in P3D V2 ORBX scenery provides varying levels of detail in different areas, and in different add-on products, with some very detailed airport areas (or scenics such as Yosemite) having more detailed mesh than the rest of the area covered.

 

I hope this is what you needed, since you gave little info on what you already know or understand about such things.

See this link which explains it well along with a nice graphic. It mentions FSX but the same thing applies to MSFS:

 

https://my737ng.com/scenery-exposed/

Just to expand on that a little, the "mesh", imagine a large fishing net, that has shape while on the ground. Shows the valleys, hills, mountains. But what it REALLY is, is numbers. Position and elevation numbers. The more of those elevation@position numbers, the more the sim/game will look like the real world, much like how pixel size and density improves the visual.

 

The penalty for those many extra numbers is data increase. It's MUCH more numbers to represent a small area. The default FS will look decent, real-ish, but remember, they are modeling the entire globe. In most places, the default is just fine, especially with particularly flat areas. But in spectacular mountainous terrain, or lots of nice hills, you may wish to have a much more detailed mesh for those areas. That way, you can make out real features. Compare to photographs of the real place. For flight sims, this may translate into more realism for your approach into bush airstrips, airports in mountain valleys, and the approach plates will make more sense to you than maybe you'll see in the default.

 

So where does the data actually come from? All those millions upon millions (billions? Probably) of elevation@position seem to mostly come from a NASA Space Shuttle mission, in which they measured those elevations, and are now public available information. I remember back in FS2004's golden era, some people would make a series of free downloadable meshes, of areas. They might divide up the Western North American mountain range the Rocky Mountains, into a series of tiles that might be 200km by 200km or so. And offer each "mesh tile" at different resolutions, so that people with modest processing and storage could still enjoy an improvement. Pick the area tiles you want, and leave the rest, or download for a long time and put them all in!

 

If all you do is fly at 40,000 ft and land at airports that are in flat terrain, this might not matter to you. But if you fly into smaller regional airports, bush strips, maybe fly to airports right beside a mountain ridge like Kai Tak or LDSP in Split Croatia, and are more adventure-seeking, want to look at interesting terrain features, then this is something you may wish to download, or even get into providing content for the rest of us to enjoy!

Thanks, people. That's about what I thought. As long as there's no FPS penalty, OK, but it seems to me there must be, notwithstanding the Orbx teaser.

 

To refer back to 35mm photography: the finer the grain, the slower the film. Same idea. Right?

Yes. And no.

 

 

See, yes, it's more data to process and store. BUT... it might not give a slower FPS on this machine, while another might struggle a bit.

 

Consider, how incredibly weak the average computer was in 2004, and compare it to what you have today. The RAM, the video RAM, the very slow disc compared to a fast SSD today. And many were using some fairly dense mesh data way back then. If it impacts your frames, then choose the next lower density mesh and that should probably work just fine.

 

Yes, it will take more to process, but your computer today, may have no trouble at all with that overhead (or may not), and you might benefit greatly with no penalty. You won't really know until you try.

The difference from a practical perspective, as it applies to MSFS, is the level of detail out of the box (actually out of the Cloud) , far exceeds the detail of a stock FSX installation, and may be better than most FSX addon scenery, I don't have FSX addon scenery to compare?? It is far better than X-Plane 11.5 scenery in stock install.

Mesh defines the 'height difference' or (lack of) 'Elevation' of the terrain, Landclass defines what category the terrain is: Urban, water, forest, dessert, mountain etc etc. In Fsim you would build your scenery starting from Mesh (at the bottom) to Landclass to Textures. I use 'Fly Away Scenery' Free Global Mesh and to me it works wonders........ https://flyawaysimulation.com/downloads/files/24690/fsx-freemeshx-global-terrain-mesh-scenery-20/ Edited August 20, 2021 by piet06273

Yes. And no.

 

 

See, yes, it's more data to process and store. BUT... it might not give a slower FPS on this machine, while another might struggle a bit.

 

Consider, how incredibly weak the average computer was in 2004, and compare it to what you have today. The RAM, the video RAM, the very slow disc compared to a fast SSD today. And many were using some fairly dense mesh data way back then. If it impacts your frames, then choose the next lower density mesh and that should probably work just fine.

 

Yes, it will take more to process, but your computer today, may have no trouble at all with that overhead (or may not), and you might benefit greatly with no penalty. You won't really know until you try.

 

Well, I tried. Loaded up the Iceland Mesh from Orbx, and tried a flight. CTD within one minute of takeoff. Removed Mesh, tried same flight (BIHU to BIIS). No problem! Must be the mesh! OTOH, I had no problem with the Italy mesh from flightsim.to. We'll see.

 

i7-8700 3.7 GHz

GeForce GTX 1070 Ti; 8GB onboard

AORUS Z370 Gaming 5 LGA 1151 ATX motherboard

16GB RAM

2 TB hard drive

27” MSI gaming monitor

There might have been a large difference in mesh data density, between the one that worked, and the one that CTD'ed on you. At least now you have some idea, that some mesh will bring improvements, but some are too much for your system to process.