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FSX Shoreline Problem on Island

After spending 10 or so hours in front of the screen, I finaly managed to make some Islands. Problem was, I had one big Island an some smaller ones arround, all overlapping the SQMID11 Grid.
Some of them are already there but needed new shorelines, also the big one, others are beeing created from scratch.

I deleted all the water, put new water poly, cut the hole in it and the islands show up. Now, in some areas the new shoreline is perfect, but in some areas I still have water behind the shore line. I sure put a wide area of landclass all arround the island, still the water shows up. Does anybody has any idea about this?
You can notice, that the land line behind the shore is not straight, so I asume it will not be due to missing landclass. There is more of this problem behind the airport in the picture.
The poly I used to cut the hole, was made from the shore line, so there is also no poly missing behind the line.

Also I don't understand why all this exclude polys will always cover a whole SQMID11 Grid, regardless how small they are. Sometimes they cover only part of it but always more than the poly itself?

Forgot: I am working here with SBX and FSX SP2

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Water does not equal a shoreline and a shoreline does not equal water, they are separate design items. You will need to exclude the bad shorelines and add back corrected shorelines. As you mention and as the SDKs address, exclusions are dealt with on large QMID blocks, so even though you may want to remove a very small piece of shoreline you will be adding back a much larger section.

In SBuilderX it is possible to take your water polygons and to convert those into lines, which can then be broken into pieces and tagged with the necessary shoreline entry. Saves some time versus redoing as a separate project.
As you can see in the picture, I already deleted the old shorelines and put the new ones.
The new shorelines were also used to crate the poly that cut the hole in the waterpoly.
So the water you can see between the new shoreline and the old landline should not be there.
How do I get the land between new shoreline and old land (shore) line?
There is already enough and wide landclass below that area.
First, all of FSX is land and water is added over the top of the land to display oceans, lakes, etc. So, the choices would be;

a.) it's default water that didn't get excluded


b.) there is a glitch in your work recreating the island

A.) sometimes occurs when the water overlaps a QMID boundary, even by a little bit, as the exclusions deal with the QMID levels addressed in the SDKs.

B.) sometimes happens and is not readily noticable. You could zip up the SBuilderX .SBP file and .BGL file and attach it to a post so that I or someone else could look at things first-hand.
Sometimes I will not exclude the default shoreline until my last step. Leaving in the default shoreline I know exactly where the default water would be and that helps sort out problems (for me, anyway). Also look at your bgl files in TMFViewer along with default cvx and worldlc with QMID11 grid displayed.

scott s.
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a.) it's default water that didn't get excluded
Yes, but why not? The excludes work on QMID Grid 11, or not?
I excluded all water polys in that area and in that grid.

Next problem is comming up:
What, if there are 2 islands within on grid? I found that I can cut 2 wholes in one water polygon (should be only one, I know) but only one shows. So do we have to fill this one grid with 2 polygons to cut the two holes? Means one polygon will overlap the other one?
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Ok, found the problem! The exclude area for shore lines and water polys was too small. I thought they would exclude everything onces they are within a 11 grid, so I made only a small exclude area overlapping a few grids. Only after I made the exclude area as big as the whole island, all problems were gone.

Also the results of slicing the polygones when they go over more grids is tricky. I found it easier to cut even a huge island out of only one large water poly and later covering the excluded water arround with some hand drawn water polys.
The exclude you make is converted to a rectangle box aligned NS-EW and that box is tested to determine of a lower priority shape is drawn. A typical water poly in a large water area will be sliced at the QMID11 boundary, so it is typical to exclude a water poly and it takes out much of the QMID11 area. But you have to look at the cvx in TMFViewer.

Here you see in some cases the water poly fills the QMID11, in other cases it is "halved" (QMID12).

scott s.
I don't realy understand all that terrain stuff, with all that QMID ad LODs and whatsorever. If you are not native English, it is realy hard to read and understand that MS descriptions in the SDKs, so I gave it up.

This was my first attempt to do some terrain scenery for FSX and so far I did it! Mostly by trial & error method.
I read in some thread here, that one water poly can have only one "child" hole poly. Here, I made one huge water poly, covering 3 or 4 QMID 11 grids and I cut some 8 or 10 island holes in it and it worked.

About the exclude poly, I found that when you make a large one, covering also at least four QMID 11 cells completely and touching maybe another four, the outer cells will only be partially (half) excluded, like QMID 12. At least as long as the exclude poly does not touch the other half of the cell.

Still have to try that TMF viewer...
I read in some thread here, that one water poly can have only one "child" hole poly. Here, I made one huge water poly, covering 3 or 4 QMID 11 grids and I cut some 8 or 10 island holes in it and it worked.
I have not had a problem with multiple "holes". If there is a limit I don't know what it is. When dealing with vectors, except in the special case of "freeway traffic" (the vectors that cause vehicle models to spawn and move over the terrain) most important is the grid defined as QMID 11. You can create any sort of vector in SBuilderX. SBX will convert the format to "shapefile" and pass that to the sdk shp2vec tool which create a bgl file from the shapefile.

Here is a simple project. I create a polygon and tag it as hydro. The polygon crosses over 4 adjoining QMID 11 quads. Then I create a second polygon and set it as a "hole" to the outer polygon. This inner polygon crosses 2 adjoining QMID 11 quads.

What happens when you create a bgl? shp2vec will convert the outer polygon into 4 new polygons, clipping the original polygon along the QMID 11 quad boundaries. Also, the "island" hole is clipped. In this case, see that it is no longer a hole, but is included as a "cut" into the 2 polygons. Most of the time this works just fine, but you need to check.

Because of this clipping process, it is easy to get unwanted areas of land in parts of the QMID 11 quad outside of your project. To avoid this unwanted land, with the QMID 11 grid displayed in SBX, drag out the corners of your hydro poly so the poly fills the QMID 11 quads.

Now use the "slice to QMID11" which will result in doing the same thing shp2vec will do. You see there are now 4 "main" polygons (the ones we want), and some small polygons in the quads outside of the 4 of interest. We can just delete those extra polygons, leaving the 4 we want.

After deleting the unwanted edge polygons, this is what is left. I changed transparency level on one polygon so you can see that the "hole" has been converted to a cut, just like shp2vec does.

scott s.
Yes, that's mostly how I did it but without slicing and cutting the overlapping polygones. But I will try to do it. Thanks for the explaination.
During the whole process I had SbuilderX crashed two or three times and corrupted the work file. So I had to start all over again. Thats why I tried to cut some time and cut more than one hole in one water poly.
It's maybe a good idea to split the whole process into more then one project. I made sepperate ones for the polys, the land & water classes and another one for rivers, roads and lakes. The airport itself I will do with ADE.

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Resource contributor
Hi Scott,
I'm having the same problem and searched. I found this thread is helpful.
Just one question, I cannot find "slice to QMID11" anywhere in S-builderX. Would you mind pointing out where is this command?


Resource contributor
Forget the question. I use the older version 3.10. This command is not exist. I guess it is avialable in SBX 3.13. I'm downloading it.