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Altitude points from SBuilderX polygons are lost in SBuilder

Hello guys

I was trying to make a polygon in SBuilderX with an altutide in each point of that polygon, but when exported as a .BLN and opened in SBuilder(FS9), I check the altitude of the points and the properties says "0" in the altitude field :confused:

Is there a way to import a SBuilderX polygon with the altitude data and use it in SBuilder(FS9)??

Thank you


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I don't think there is a way to import the elevations from SBuilderX.



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FSDevConf team
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You are going backwards in versions. I suspect that there is no backward compatibility for this.

[SBuilderX install path]\Help\SBuilderX313.chm > Contents > SBuilderX Reference > File Menu > Export states:

"Export-SBuilderX SBX ... - The SBX format is exported in a text file and can be read with Notepad.

Advantages of SBX files:
in many cases you can debug your project if anything goes wrong by examining the SBX file
the selected state of items is saved so that when you import the SBX file the same items are selected as when you exported the project
if you want to merge 2 projects - Project1 with Project2 - each in its SBP files, you open Project2 and export as temp.SBX. Then you open Project1 and you append temp.SBX. Note that you can not append SBP projects
Disadvantages of SBX files:
the files can be very large
you lose land or water class scenery when you export a project with class scenery.

Export-Surfer BLN ... - The BLN file format is a very simple XYZ TXT format for data interchange. Many GIS programmes can export in this format.

Note 1: you lose the BGL properties of lines and polygons when you export to a BLN file; also you are limited to lines and polygons.
Note 2: in version 2.05 of SBuilder we changed the header in order to make the format compatible with other GIS programmes. For example, in version 2.02, the line 5,My_Line was 5,0,My_Line. This caused problems with the header being interpreted as a point in some GIS tools.
Note 3: in this example the character "," is used as a separator. You change this character through the SBuilderX.ini file. If you want the numerical values in the BLN file to be separated, for example, by a tab you need to edit the SBuilderX.ini file so that the following line is:


[SBuilder install path]\HTML\SBuilder205.chm > Contents > SBuilder Reference > File Menu > File Append states:

"Append - SBuilder SBX
The "SBX format" is very easy to read as the files are standard TXT files. Combining the facility to create a SBX file (using Export SBX) and the Append SBuilder SBX command you merge projects very easily.

If you want to merge 2 projects - Project1 with Project2 - each in its SBP files, you do the following:

Open project1.sbp and export it as temp.sbx
Open project2.sbp and append temp.sbx
Save project as merged_project.sbp
Note: the difference between Import SBX and Append SBX is that in the first case the existing project is cleared before any data input.

Although IIRC one can export an SBX file from SBuilderX, I'm not sure if that SBX file is then able to be opened by SBuilder for FS9.

If the FSX SBX format can be "ported" to the FS9 SBX format, I'm not sure that data contains elevation for polygon vertex points.

Perhaps using BLNMARKER might be an option instead: :idea:


CAVEAT: The FSX world model is different (read: more accurate) than the FS9 world model.

Beware: some terrain attributes in FS9 are off by a half of a Kilometer in varying directions compared to positions in the FSX world ! :eek:

Also, terrain mesh resolution in FS9.1 is limited to no more than LOD-11 (19.2 Meters between data points on the ground) compared to FSX, so in addition to terrain elevations being different in FS9, limitations of one's ability to benefit from terrain object "shapes" created in FSX may make it impractical to port terrain data derived from the FSX world model into the FS9 world model.

It looks like you may be wanting to create 'sloped / tilted flattens' in FSX and "port" the data into FS9 to create what the FS2004 SDK refers to as a 'LWM3 polygon'.

IMHO, 'LWM3 polygons' are best created directly within the FS9 environment... if they are to be used in FS9.

IIRC, 'LWM3 polygons' can be made via FS2004 SDK methods, or via SCASM LWMPoly3( ) methods for FS2004.

Flatten polygons in FS9 can be either "flat" LWM2, or "sloped / tilted" LWM3 BGLs made via FS2004 SDK or SCASM methods.

Thus, both FS2004 SDK and SCASM LWM3 flatten polygons may have individual elevations assigned to each vertex (point).

However, one must be careful when mixing both LWM and SCASM flattens and texture layers in the same area:


NOTE: Regardless of which BGL type is used for one's "flat" or "sloped / tilted" flattens, the maximum resolution at which the polygon Lat/Lon vertex coordinates and elevation data points can be rendered will depend not only on the source data precision, but also on the resolution of the currently 'active' underlying FS9 terrain mesh (ex: LOD-11 would be higher resolution than LOD-8).

If one uses LOD-11 resolution source data to author one's flatten polygons, but one's FS9 configuration is currently using or limited to a terrain mesh BGL which is only LOD-10 (38.2 Meters between elevation data points), one's intended LOD-11 flatten polygon vertices will 'alias' or 'fall back' to the nearest available LOD-10 quad tile "area point" vertices (each terrain quad or 'cell' is subdivided into 256 resolvable area points).

Consequently, with an "active" LOD-10 terrain mesh BGL, FS would only be able to render the polygons at a LOD-10 resolution instead of that which might otherwise have been possible (due to the internal LOD-11 resolution source data) for one's polygons.

So, to get "predictable" results in FS, one's "active" terrain mesh BGL resolution should match the source data resolution of LWM BGLs.

CAVEAT: One must ALSO set TERRAIN_MAX_VERTEX_LEVEL (aka "TMVL") in FS9.Cfg at a value which enables a desired mesh LOD display:

LOD-11 @ TMVL=21, LOD-10 @ TMVL=20, LOD-9 @ TMVL=19, LOD-8 @ TMVL=18 etc.

LOD - TMVL Calculation: LOD + 10 = TMVL required to allow FS9 to display a specified terrain mesh LOD

FS 2004 version 9.1 "limits" terrain mesh vertex display to no more than LOD-11; those Area Points are like "miniature Quad Matrix Grid Cells" LOD-21 in size

Thus, no further change in terrain "shape" will be rendered beyond LOD-11, although higher (ex: LOD-12) terrain mesh info will still be internally processed but rendered with appropriate changes in terrain slope textures instead of actual changes in terrain slope incline gradients. :teacher:

BTW: SBuilder for FS9 has a "Make Flatten" feature via a 'VTP High Resolution Photo-mesh BSQ/BMP conversion technique'.

However, that method seems to be limited to creating "sloped / tilted flattens" with a resolution based on an LOD-8 grid rather than a full LOD-11 grid which the FS9 rendering engine theoretically supports (with FS2004 'version 9.1 patch' applied).

And, again, we must remember...

* In FS2004 RTM (aka FS version 9.0) without the 'version 9.1 patch' applied, terrain mesh resolution is limited to LOD-9 (76.4 Meters between elevation data points on the ground).

* Although FS9.1 "reads" FS9 SDK Resample generated (aka "FS9 format") terrain mesh data files containing LOD's higher than LOD-11, the actual terrain vertices (and thereby the physical shape) are not "rendered" beyond LOD-11.

* However, the FS9.1 rendering engine will begin using different "slope textures" (ex: rock faces on hillsides / mountain sides or peaks) with FS9 format terrain mesh BGLs having LODs of 12 or above -IF- non-photoreal land class textures are active in an area. ;)


These threads might help provide some background on implementing LWM3 polygons via SBuilder for FS9:









FYI: It may be possible via SBuilder to copy "appended" default FS9 LWM flatten BGL polygon vertex (point) data and edit to create a 'new' LWM flatten BGL ... leaving the original default FS LWM BGL file unchanged.

That "new" LWM flatten BGL can then be placed in a higher display priority layer above the default airport area LWM flatten BGL. :wizard:


An example process for appending / copying / editing / deriving 'new' LWM2 BGLs for default "water flatten" data in SBuilder is here: :stirthepo


No easy answers, IMHO, but... sometimes Google is your friend:


Another (esoteric) possibility via Falko Dienstbach's "DEM2LWM3" utility (for higher LOD output than a BSQ method yields ?):


Translated version of Falko Dienstbach's "download" page:


One may also use Jim Keirs' "Slartibartfast" to create, derive and edit content to be used for terrain polygons and mesh files:



rhumbaflappy; said:
Posted 15 September 2010 - 11:17 AM http://forum.avsim.net/topic/295799-error-in-hsp-greece-mesh/

Hi Panos.

It doesn't matter where the mesh is loaded from. You can't have elevations of -32640m and -250m and believe the mesh is OK. The data is not right. Any version of TMFViewer would confirm this. And end-users are also confirming the problem.


In the zip file I loaded and checked the 2 mesh files with TMFViewer. Each file has the serious problems I noted above. It is caused by Slartibartfast. When using Slarti, the Source files must cover a considerably larger area than the end mesh. The Destination must not "UseSourceDimensions", but must specify the coordinates ( it might even need slightly expanded coordinates ).

Additionally, one might wish to try using "RingPiece" to generate SBX files for SBuilder:

Posted 16-04-2010, 18:05 http://www.newsite.fsdeveloper.com/forum/showthread.php?t=19477

Version 3 of RingPiece works very well. You can append the SBX file to either SB9 or SBX. Me likeee.

Small mistakes in the line can be easily fixed in SB?, as you can drag vertices or delete/add them.

Smoothing might be needed, as more vertices will mean larger BGLs... and the internal memory management of SB9 and SCASM may choke on complex polys/lines.



Posted 26-05-2011, 12:29


Heads Up ! :alert:

There's an apparent workaround for FSX scenery projects to be made with 'new' versions of Google Earth (aka "GE") KML when subsequently processed via FSX-KML, RingPiece etc. to generate SHP or SBX output files.

FYI: FSX-KML, RingPiece etc. expect KML data in the 'original' GE KML format; certain changes have been made in the 'new' GE KML format.

The solution may be pre-processing one's "NEW" GE KML format output data via "PreFsxKml", a utility graciously provided by author "Angelus1971':

Discussion here: http://www.fsdeveloper.com/forum/showthread.php?t=33180&highlight=Google+Earth

Download here: http://www.fsdeveloper.com/forum/downloads.php?do=file&id=96

NOTE: When PreFSXKML opens the FSX-KML GUI, click File > Save so one's pre-processed KML file updates to GE's new format.

BTW: The current project "pre-processed" KML and compiled SHP files are in: [FSX-KML install path]\Output\ folder. ;)

Hope this helps ! :)


FYI: For more info, enter "RingPiece" as a query string at FSDeveloper 'Search' page:



PS: Or perhaps Scruffyduck could add output of airport flattens as "flat" Area 16N or LWM2, and "sloped / tilted" LWM3 polys to make ADE9X more helpful to those working with FS9 airports ? :duck:

Hope this helps ! :)

Last edited:


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FSDevConf team
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PS: Or perhaps Scruffyduck could add output of airport flattens as "flat" Area 16N or LWM2, and "sloped / tilted" LWM3 polys to make ADE9X more helpful to those working with FS9 airports ?

On the list (a very long list) :)