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FSX Waterclass and Hydros broken?

I am having a strange problem in my latest scenery experiment. On land side (not on the ocean) I created several shapes that will represent shallow water.

I tried setting them to WaterClass Shallow Non Perennial but I get an error that it could not find some TIF file even though this is a standard FSX water class.

So, I changed them from that Waterclass to just a Hydropolygon drawn on land. In this case I get no errors but no matter which hydropolygon tag I select, it will not show up on the scenery.

What am I missing? I understand you only use PolygonHole if you are drawing an island on water areas (remove the water).
I got the WaterClass error fixed, I had to reconfigure FWTools to use the real path instead of the broken DOS-type path it stored during installation. Now when I tag a polygon with a WaterClass I do not get any compilation error.

The problem is, when I use a WaterClass the *WaterClass.BGL file is generated but when placed together with the rest of the scenery (yes, installed in FSX) the polygon is not showing any water.

Using Hydropolygons work as long as one does not use any Non Perennial.


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Resource contributor
I have moved this thread to the FSX KML forum. Perhaps someone with familiarity here can help you, as your problem is specific to that program.

Hi Folks

lordofwings -
Are you testing Non Perennial's display in the appropriate season ?
i.e. Winter or rainy season ?

Perennial == Lasting or remaining active throughout the year, or all the time.

Non Perennial == Seasonal, not present all year round. i.e. Dries out in summer.

Also if your waterclass and landclass are in seperate files,
the landclass may be overriding the waterclass.

Try renaming your waterclass.bgl with an underscore prefix as _waterclass.bgl

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I have the following Beagles in my scenery directory:

aptPA-MPCE-DEGT.bgl <--- airport (FSX Planner)
cvxPA-MPCE-DEGT.bgl <--- terrain (FSX KML, BGL compiler)
PA-MPCE-DEGT_Waterclass.bgl <--- inland water bodies (FSX KML, Resample)

I wonder if my waterclass polygon must be a tile of a given size, I use it for some lakes that are supposed to be brown/greenish not blue.

Good insight about the (Non)Perennial, however I am developing scenery for the tropics (dry/rainy seasons only). I am testing them now (June) which corresponds to the rainy season here so even in that case they should have been full of water.
Lord of wings- Yes, your polygons will need to be quite large in Google Earth in order to generate 1 pixel in a water class file. For these 'class' files, each pixel is around 1 km and depending on the sample method used, there may not be enough waterclass information given from very small water polygons to generate a pixel.

The easiest way to test if your process is working is to simply make a massive polygon covering your area (say 50 km/50km) and then tag with a brown water class and resample.
Thanks for the info Timmo, unfortunately that wouldn't quite work for me because the region I work with (Panama) is very narrow and small (the whole country), so if I do that it will also adversely affect the ocean part. I guess I stroke a limitation in FSX.