Don't understand " HD mesh V2 for photosceneries"

[Scripted4u 3]

Over at http://www.simheaven.de they describe the HD Mesh V2 for Photosceneries ZL17/ZL16. Is this the exact same thing as the HD Mesh V2 that was recently released? If so, why is it described as mesh for photoscenery?

[Longranger 148]

 If so, why is it described as mesh for photoscenery?

Because they are ohnly the mesh components that are needed to modify the existing photosceneries to HD Mesh 2 standard so that you don't have to download the photosceneries again.

[Scripted4u 3]

Why wouldn't you just download the HD Mesh V2 that's available elsewhere then?

 

I guess I must be confused. If someone had say Swtizerland Photoscenery ZL17 already installed, then why not just go download HD Mesh V2 for Europe which covers the Swiss area?

 

In other words, is this "HD Mesh V2 for Photosceneries" something special that can only work with the listed photosceneries?

 

 

[Murmur 3,941]

alpilotx will give you a more precise answer, however things should be something like that: in x-plane, scenery is usually distributed as a 'merged' object, containing all the elements: base mesh, landclass/photoscenery, autogen, etc. So when you download this simheaven photoscenery, it contains also the base mesh (terrain triangles/elevation data). However, scenery can be distributed also as (so called) ' overlay' scenery. In this case, the overlay scenery simply 'drapes' above the underlying base mesh. From what I understand though, overlay scenery has worse performance (read FAQs on simheaven website, where this is mentioned). I think this is the reason why scenery is usually distributed as 'merged' as is the case with simheaven.

[MdMax 233]

I thought it's only the mesh and water for faster loadings. With photosceneries you don't need landclass data. But I may be wrong.

[alpilotx 505]

Oh my ... thats why I intend to write a more detailed documentation on this topic (in the coming weeks, when my brain is ready and free to do it). But I try to give a short - as short as possible - summary here:

 

Effectively my "HD Mesh Scenery v2" and the "HD Mesh v2 for Photo Sceneries" from SimHeaven are identical ... BUT, they have one very very big difference: The way how they map textures to the landscape!

• "HD Mesh Scenery v2" has a "wild" patchwork of complex, overlapping (to make soft blending possible!), triangle patches to mix the generic textures in a way, that they represent  natural features (landclass data) in a natural way. It looks remotely something like this (each color approximately represents a different terrain type / land class):
• whereas "HD Mesh v2 for Photo Sceneries" needs a very different approach with textures. It doesn't needs to have those wild triangle patchworks, as it doesn't map generic textures, but instead "real" photo textures, which are quadratic patches of .. well ... images. So, what it does (well, its done by the tool g2xpl!) is, that it re-cuts the existing triangle mesh in a way, that it forms quadratic patches (even removes the overlapping triangles, as it doesn't need artificial texture blending) which each get one(!) photo texture element mapped to. Thats why the mesh of same region it looks much more - uhm - structured, when used with photoscenery:

BUT, everything else (there is a lot), which is contained in a standard base mesh too, remains identical ... like:

• road, railroad, power line network
• autogen zones and facades
• forest polygons
• and the water triangles in the scenery

Whats also important to understand, that those triangle patches always map to an abstract artwork definition file NOT directly textures. Those are the "ominous" TER files ... and each of those TER files then points to the texture or textures (yes, it can do many tricks via shaders etc.) it needs to fill that triangle patch. In the case of photoscenery, each of those TERs is usually "just" pointing to the "real" photo texture.

 

This abstraction has also another positive side, which SimHeaven "uses" a lot, even if many don't understand it: as long as different versions of his "photo scenery" DSFs all reference the SAME (same name!) TERs, you can easily swap the DSFs out, without the need to replace / re-download the entire (big and traffic hungry) texture set!

 

And finally, as someone pointed out: even though X-Plane can drape fototextures on arbitrary base mesh, this approach is performance hungry (and memory hungry) and is only suitable (and the very good!) for small sceneries like airports. For big - entire 1x1 degree DSFs - scenery tiles it would just plain kill your machine! Thats why its a very good idea to not drape, but re-cut/re-build the mesh and let it directly map to those TERs (and then photo textures). Ben Supnik blogged about this for example here:

http://developer.x-plane.com/2008/09/meshtool-vs-draped-polygons/

[Scripted4u 3]

Thankyou, so I need the Mesh for Photoscenery V2, instead of Mesh V2.

 

I notice that Mesh Europe V2 ZL17 is 9GB in size. I assume that is not including the ZL17 Photoscenery textures, correct?

[alpilotx 505]

I  assume that is not including the ZL17 Photoscenery textures, correct?

Yes, I assume that too ... ^_^ SimHeaven did this, so people who already have his "older" don't need to download 100s of Gbytes of textures again, but only the "replacement" DSFs. Nevertheless, its very very important that you read his README very carefully!

[tonywob 4,768]

Basically if you use photoscenery from simheaven, you need this to patch to upgrade the mesh on your photoscenery to v2, otherwise download directly from alpilotx's site :-)

 

And trust me , it's worth the effort

[Scripted4u 3]

Is this you alpilotx?

 

http://zonephoto.x-plane.fr/Cartes.php

[alpilotx 505]

No, this is me: http://www.alpilotx.net (silly question)

Basically if you use photoscenery from simheaven, you need this to patch to upgrade the mesh on your photoscenery to v2, otherwise download directly from alpilotx's site :-)

 

And trust me , it's worth the effort

Yeah, its worth the effort if you are after HD Mesh Scenery v2. BUT, if you want the photoscenery based on the HD mesh v2, then the download from my site will not help (at least not in an easy way - you would need to use g2xpl yourself). The only way to get photoscenery combined with HD mesh v2 is currently via the - little bit - complex procedure from SimHeaven ...

[Scripted4u 3]

It may be a silly question for people who know. But I don't know, that's why I asked.

 

You gotta admit, it's fairly confusing when you come from FSX where mesh is mesh and photoscenery is photoscenery.

[captain420 3,099]

Still confused by this. So for newcomers who freshly installed X-Plane, would it be better just to download the HD mesh v2 for photosceneries directly from simheaven instead since it includes the photoscenery. Does this also mean the osm files like Osm North-America is still required or not? Since these files are huge, I want to make sure I don't waste time and bandwidth by downloading the wrong stuff.

[tonywob 4,768]

 

 

Still confused by this. So for newcomers who freshly installed X-Plane, would it be better just to download the HD mesh v2 for photosceneries directly from simheaven instead since it includes the photoscenery. Does this also mean the osm files like Osm North-America is still required or not? Since these files are huge, I want to make sure I don't waste time and bandwidth by downloading the wrong stuff.

 

No it doesn't include the actual photoscenery, this is only usual if you've already downloaded and installed the photoscenery from this site and wish to update it to the new mesh. The OSM scenery is seperate and can sit on top of the photoscenery or standalone and adds real buildings and forest where available.

[alpilotx 505]

It may be a silly question for people who know. But I don't know, that's why I asked.

 

You gotta admit, it's fairly confusing when you come from FSX where mesh is mesh and photoscenery is photoscenery.

Sorry, that might have been a bit too harsh ..... but when my website is always mentioned in the footer of each post, then there might be some point to it.

 

And of course, when ever you dive into a new ecosystem it takes some time to learn how it works ...