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FSX Creating new islands in the sea

I want to update some default scenery by adding some missing islands into what is shown as sea in the default FS scenery. My question is how do I go about it?

I would also like to know which Landclass I should use to represent tree vegetation on a tropical island (caribbean).


Resource contributor
Dear Lordof:

You've got to create a water polygon with holes, previously you must exclude the default water polygon.

Search on Google about FSX Landclass table, there is a set of pictures by landclass number.

Alfredo Mendiola Loyola
Lima, Perú
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Could you clarify that a little bit? I think that for making a lake in FSX land (not water) I first have to create an area tagged PolygonHole, that makes it water. Then I have to use the same area and tag it with Landclass Lake Perennial or something like that.

Now for this other project I want to create some real life islands that are not in FSX. What would be the tags (and in which order) I would have to use?
This is basicly my question re: A few questions. The PolygonHole is not working right. First it doesn't work .... leaves the waterpoly intact then after I placed all polygons in the same folder, I get a lake in the shape of the island. I have 4 polys .... 1 Exclude__WaterPoly, 1 Exclude Shorelines, 1 WaterPoly_Ocean, and then the WaterHole poly.
Should the First 2 be out of the folder?


Edit ..... I was looking at this shot this morning. Looks like lakes! Lakes are made in SBuilder by drawing lines clockwise, Islands are made in SBuilder drawing counter clockwise. I drew these counter clockwise. I reversed the vertices and to clockwise and got islands. Looks like this method is opposite of SBuilder. On to the shorelines. Thanks guys .....
Joe W


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This is easy, I did about 25 islands yesterday evening :)
I do it this way:

1. draw a generous hydro polygon, make it transparent
2. draw a plain polygon of the outlines of the island, leave it opaque.
3. draw a simple exlude hydro polygon around it, adjust the transparency so you see your island again. Stay inside the hydro poly from step 1 with it.
4. mark the opaque plain island ploygon (the whole thing, not a vertex!) with "set as hole" and (in polygon drawing mode!!!) and assign it to the hydro poly in step 1. Be sure to get the right one in a complex setup. Now, if you work with satellite-backgrounds, you should see the background from the sat-image through the "hole". Then you did it right. In FSX you will see whatever landclass is defined for that patch of land showing through the hole. Remember, there is always land under the water polys. Of course you also can set another landclass poly with the exact circumference of the hole on the island, or rework the landclass underneath with the LC-tool, etc etc.
5. draw shorelines, make elevations, etc

If you re-create a default island that has already been there you might have to exclude the old shorelines or other terrain features first.
And just in case you want to create several small islets near each other, you can set them all on one hydro poly, Theres no need to define one for each islet.

@ Joe, I think the clockwise drawing only refers to the shorelines and the direction of the waves on them. Clockwise drawing = land in the middle, waves from the circumference. If you draw it in the wrong direction, no prob, the effect can be reversed in SbuilderX without deleting and drawing the shoreline again.

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Are you describing an FSXKML procedure? I have the latest FSX_KML and I don't see any "Set as a Hole" checkbox or option anywhere. I can edit polygons and set the altitude of all vertices at once and assign the polygon a tag.

BTW. Just did an experiment, I named my new airport (the one that resembles more the real location) PX02 (as the original), I also create a separate BGL for the updated airport altitude. What I see on the GPS is a single airport rather than two and that is ok, that one is PX02. The rest however is totally wrong, the airport backgrounds are there but both runways disappear, the new one is only visible if you are at runway level. The scenery and terrain near the new airfield location are totally messed up and the airport locator shows the data of the old (FSX original) airport which has wrong city and no state information which I am also updating on the corrected version.

Apparently I can not do that and will have to let FSX insist on having both. But I can't seem to have the old airport runway disappear, nor its airport background neither its sunk state (it appears below terrain with FSX Mesh freeware and above terrain in a mesa with default FSX elevations.

I am using the 'Exclude_Airport_Backgrounds_MaskClassMap' tag in the old airport location in hopes to have the runway and airport background disappear and also erase the flatten so that the whole thing appears at the mesh's elevation as if there was no airport there.
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Ohhh, my bad, I described the SbuilderX procedure. I didn't notice I was in the FsX KML forum.
Sorry if I confused anyone!

Islands in SBuilderX


I've tried using the advice you gave, and all went well until I compiled the bgl.

When viewed in FSX all I managed to do was exclude a huge rectangle of water leaving default landclass, rather than just the island area I was hoping for. :s



Resource contributor
That is correct, you first exclude a larger area (rectangle) and then cover this area with water. Below the water poly you place a polygonhole poly to cut out the actual island.
Is there a reason why you shouldn't do the island with ADE ? Easy and simple .
Just started this project , an island in mid-Atlantic ;)


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Resource contributor
Lots of reasons actually. You can (afaIk) only do very rudimentary things with tools like ADE when it comes to terrain. It's way better to use FsxKml for those things.
Lots of reasons actually. You can (afaIk) only do very rudimentary things with tools like ADE when it comes to terrain. It's way better to use FsxKml for those things.

What exactly do you mean by rudimentary . An island is an island , is it not ?
Granted , the surface of it is not harden but this is an issue that one can overcome easy enough .
Is it different with FsxKml ? Is the surface harden ? Because if it's not , sorry , but l see no difference .


Resource contributor
Yes, if you define an island as a simple shaped and textured polygon painted on the sea, then there is probably no easier way than to draw a polygon with a tool like ADE (which I used a lot over the years, I really like ADE a lot).

If you want to create a realistic island including realistic landclass, autogen, vector data like streets or rivers, lakes, villages, shorelines, custom landclass,... then you will soon reach the limits of airport design tools like ADE.
One of these days , when l'll have the time , l'll see how far l can stretch ADE , but up to now l have no problem with street , rivers , villages ,lakes and the such .
Nevertheless , l'll have to see an island made with all the goodies you mentioned made with FsxKml to be convinced . Maybe you could direct me to one .
Thanks for you trouble Thorsten ,

Impressive l must say , but l've seen around a lot of realistic sceneries made by professionals and sold for a price . They do that for a living . Good for them.
l would love to see an island made with the tools you say or whatever is available , made by someone for whom developing is a hobby ?
Me , l am not a developer , just a guy , who loves FSX and ADE plus Arno's tools , and kill time by making unusual airports in the horrible FSX terrain of Greece
for my personal satisfaction not for publishing .



Resource contributor
Good point, but actually this is why I tried to motivate you to use fsxkml in the first place, because it's easy to learn, you find a lot of information about it here in the forum and the results are very satisfying.
I would suggest that, if you have something special in mind, post it here and ask the other guys how they would do it. You'll get a lot of good input and will be able to get a nice scenery within a few hours work.
l appreciate your comments and interest to motivate me to use FsxKml , but l am a sob who lives with " seeing is believing " , never went to a blind date :D .
So until l see a hobbyist's island made with FsxKml which will look much , much , better than mine ( l worked a bit more on it ) , l will stick to ADE.
Besides l never said or thought l'll put it in this forum's showroom or publish it .

Thanks again

PS . Congrats on Bayern . Great tactics , great match .


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Resource contributor
1st of all, I live in Kiel, that's 800km away from Munich, so I'd rather you wish me luck for THW Kiel's champions league run (Handball) than for Bayern Munich, lol. :D

2nd, I think your island looks good as it is, and you're probably right that FSXKml would not help much at this point. I would rather create more detailed apron polygons to make the airport look less artificial. But beware: if you place several airport polys on top of each other you need to watch the drawing order (hard-coded, can't be changed).