• Which the release of FS2020 we see an explosition of activity on the forun and of course we are very happy to see this. But having all questions about FS2020 in one forum becomes a bit messy. So therefore we would like to ask you all to use the following guidelines when posting your questions:

    • Tag FS2020 specific questions with the MSFS2020 tag.
    • Questions about making 3D assets can be posted in the 3D asset design forum. Either post them in the subforum of the modelling tool you use or in the general forum if they are general.
    • Questions about aircraft design can be posted in the Aircraft design forum
    • Questions about airport design can be posted in the FS2020 airport design forum. Once airport development tools have been updated for FS2020 you can post tool speciifc questions in the subforums of those tools as well of course.
    • Questions about terrain design can be posted in the FS2020 terrain design forum.
    • Questions about SimConnect can be posted in the SimConnect forum.

    Any other question that is not specific to an aspect of development or tool can be posted in the General chat forum.

    By following these guidelines we make sure that the forums remain easy to read for everybody and also that the right people can find your post to answer it.

Export ground polygons to SHP missing output

G

GaryGB

Messages
9,034
Country
us-illinois
Hi Arno:

MCX build February 20, 2026 does not seem to complete actual writing of a ESRI *.SHP file for a G-Poly from inside a FSX Accel XtoMDL Scenery Library Object BGL.

MCX states "Finished writing of file [filename.shp]" in event log.

Although Windows shows a recent *.LNK file was created for that [filename.shp], the ESRI *.SHP file output ...is nowhere to be found. o_O


Also, MCX (same build) Ground Polygon Wizard does load that FSX Accel XtoMDL Scenery Library Object BGL into MCX GPW GUI.

However, if MCX steps forward into the BGL to preview a specific G-Poly for processing in GPW GUI, GPW stays on the first library object. :oops:


Thanks in advance for looking into this. ;)

GaryGB
 
Last edited:
Hi Gary,
GaryGB said:
MCX build February 20, 2026 does not seem to complete actual writing of a ESRI *.SHP file for a G-Poly from inside a FSX Accel XtoMDL Scenery Library Object BGL.

MCX states "Finished writing of file [filename.shp]" in event log.

Although Windows shows a recent *.LNK file was created for that [filename.shp], the ESRI *.SHP file output ...is nowhere to be found. o_O
Click to expand...
I just downloaded the last official build and tried to export a SHP file from it using the export scenery button. That works fine, I get the SHP with the polygons of the object.

Did you do a clean install of the new build? If you install it over an old development release I am not sure if that could give issues.

GaryGB said:
Also, MCX (same build) Ground Polygon Wizard does load that FSX Accel XtoMDL Scenery Library Object BGL into MCX GPW GUI.

However, if MCX steps forward into the BGL to preview a specific G-Poly for processing in GPW GUI, GPW stays on the first library object. :oops:
Click to expand...
I can't reproduce this issue. When I load a BGL file with multiple objects, I can use the green arrow buttons to navigate through them as normal.
 
OK. thanks for testing.

FYI: Note that I did not remove any existing prior MCX builds which are also installed and used as described below.


I downloaded and un-zipped the latest DevRel MCX build, then created a shortcut to MCX' .exe with Admin privileges.

That shortcut, named "MCX 02-20-2026", was placed in my Windows-10 Pro (x64) current user profile SendTo folder:

C:\Users\[current user profile name]\AppData\Roaming\Microsoft\Windows\SendTo


I then browsed in Windows Explorer / File Manager to the BGL > Right-click: > SendTo > click: MCX 02-20-2026 link.

MCX loads the BGL > MCX Menu > Wizards > Ground Polygon Wizard > browse to the BGL > MCX loads the BGL in GPW

GPW's (separate window) dialog box loads object # 1 in the BGL


In MCX 3D Preview pane, if I manually step past object # 1 in the BGL, GPW stays at object # 1 in the BGL.


I'll test this further today with several prior MCX builds which are also installed and used as described above.:scratchch

IIRC, MCX' DevRel build is not compatible with hardware limitations / runtime DLLs in a Windows-7 (x64) laptop I also use.

GaryGB
 
Last edited:
GaryGB said:
In MCX 3D Preview pane, if I manually step past object # 1 in the BGL, GPW stays at object # 1 in the BGL.
Click to expand...
Correct, that has always been how it works. Changing objects in the preview does not affect the GPW. The assumption of the GPW is that the file that you load only contains one object.

GaryGB said:
IIRC, MCX' DevRel build is not compatible with hardware limitations / runtime DLLs in a Windows-7 (x64) laptop I also use.
Click to expand...
I guess that is the case since I moved to .NET 8, which is not supported on Windows 7.
 
arno said:
Correct, that has always been how it works. Changing objects in the preview does not affect the GPW. The assumption of the GPW is that the file that you load only contains one object.
Click to expand...

I do not recall seeing that MCX GPW requirement documented anywhere previously; but I shall note that for the future. :pushpin:


So, if a BGL (SCASM / ASM, or MDL-based) has multiple G-Polys, we must manually export separate (1) G-Poly BGLs to work with GPW ? :rolleyes:

That explains why a discrete (1) G-Poly SCASM / ASM BGL was able to complete actual writing of a ESRI *.SHP file for a G-Poly.

I also noticed when attempting to process a multiple "G-Poly" FSX Accel XtoMDL Scenery Library Object BGL via Export Ground Polygons To SHP, that the MCX Event log had statements "Skipped" for objects that had no placement within the same loaded XtoMDL Scenery Library Object BGL.


Could future build(s) of MCX allow processing of (multiple G-Poly) XtoMDL Scenery Library Object BGLs for GPW or SHP export ? :idea:

To enable that, can we concurrently load a separate placement BGL containing required info for each Scenery Library Object BGL G-Poly GUID ?

Thanks for your consideration of these options. :)


I shall test further to see if MCX DevRel GPW handles (multiple G-Poly) SCASM / ASM Scenery Library Object BGLs for GPW or SHP export. :coffee:

GaryGB
 
Last edited:
Hi Gary,

You are right that this is not really documented, but it is how the GPW has worked since I made it (must be over 10 years now). You need to remember that the GPW was designed so that developers could make their ground polygons in a tool like GMax like they did for FS2004 and then use the GPW to adjust it for the curve of the earth. In that use case the input is one file with all the ground polygons. The GPW will then apply the earth curve and split it into multiple objects.

If you have a BGL file that already contains multiple objects, most likely these are not flat ground polygons that the GPW expects as input. Running the GPW on polygons that already have the earth curve applied will lead to issues.

MCX can only write polygons to SHP for objects that have placement information indeed. Else it does not know where the place them and in the SHP each polygon needs to have a position. So those without placement are skipped. But that is a different issue. If you would have a BGL with multiple ground polygons objects, each of them would still have a placement.

The export SHP works on the entire scenery, so that will export all object in that scenery. The GPW works with the assumption of one object like explained. So in that case you would have to run the BGL through the Scene Builder Wizard first to combine it al into one object.
 
[EDITED]

FYI: I'm testing a workflow to transition FSX G-Polys to MSFS 2020 for direct display in XtoMDL BGL format via use of Layout and Manifest .JSON files in a Package root folder accompanied by a local package-named nested sub-folder within a \ContentInfo sub-folder.

https://www.fsdeveloper.com/forum/threads/draw-order-of-gps.460365/post-936475

https://www.fsdeveloper.com/forum/threads/draw-order-of-gps.460365/post-936480


I can then convert into FSX XtoMDL BGL format G-Polys into glTF format ...for use either as MSFS G-Polys- or as Projected Mesh objects- to be merged with MSFS terrain Polygons.

[END_EDIT]

GaryGB
 
Last edited:
I can hardly follow what you are saying since you throw so many extra terms in there. But if you are working with FSX GP files, they are curved already and you should never run them through the GPW again. Just use the export object or export scenery options to export them to different formats.
 
Hi Arno:

Thanks for the reminder that "true" G-Polys for FSX / P3D are adapted to fit a FS 'curved Earth' 3D world model. :)


AFAIK, MSFS also has a 'curved Earth' 3D world model, and IIUC, it seeks to integrate EGM-2000 into its world configuration.


I'm curious if you have tested whether MSFS' curved Earth 3D world model "fits" FSX / P3D curved Earth 3D world model ? :scratchch


The tile system of MSFS' BING Maps / MS-VE vs. FSX / P3D SDK shows some difference in actual quad tile extents / coordinates.


IIUC, FSPackageTool internally computes curved Earth 3D world model corrections for terrain Rectangles / Polygons.


IIRC, MSFS SDK does not explicitly describe use of G-Polys, but instead describes Projected Mesh.

If we use > 100 Meter extent FSX / P3D XtoMDL G-Polys in MSFS, is MCX Earth curve correction editor use still required ? 🤓

GaryGB
 
Last edited:
My short answer is that I don't know. I never made ground polygons for MSFS myself. So these questions would have to be answered by somebody who did so.
 
You must log in or register to reply here.
Back
Top