Problem with above sea level lake elevation data in default scenery

[andrewlsummer]

Issue: Problem with above sea level lake elevation data in default scenery

Hi guys,

I have made a DEM of an location which features a lake above sea level.

Since converting the DEM to a BGL using Resample I have found out that FSX default scenery has an explicit flat layer of elevation data in the location where my location has a lake above sea level.

What I found out is that FSX ignores the part of my DEM which has the lake that FSX has been pre-programmed with. However, FSX accepts the rest of the area covered by my DEM and displays it correctly. If I use another DEM from another source, FSX also ignores my elevation data for the lake and substitutes its own.

The altitude of the terrain that FSX has explicitly added for the lake is about over 100 meters higher than the lake in real life, and the fake elevated FSX lake area dwarfs the hills that normally surround and overlook it.

The DEM I have made also features other lakes and ponds that I have flattened and this matches my Ground texture, Water mask and Blend mask. So I need to get rid of the FSX elevation data that is fixed in my location.

Are there any switches I can add to my INF file to force my elevation BGL to override the default FSX elevation data? I mean it always does by default, except in this case where FSX has explicitly programmed fixed terrain data for my area.

I don't use SBuilderX because I normally work with 20k x 15k pixel textures which it can't accept, so SBuilderX isn't an option unless someone specifically has a description of how to generate an elevation BGL in SbuilderX or make purely an extrusion area in SBuilderX that can work alongside my other BGLs.

Just for your info my preferred work method is creating ground-water-blend-BGLS, elevation BGL + autogen scenery, so if you have a solution that can work with this that'd be great! And if anyone can give a quick solution that I can plug my lat-lon coords into that'd be awesome too.

I'd be happy to give someone a generous sum over Paypal if someone can solve the above problem for me because it is killing me when I'm so close to make my best scenery ever!

Yours, Andrew

[Golf-HotelDelta]

You will need to exclude the relevant default lake hydro-poly and create a new one at your mesh height. If your mesh is adequate, you could probably get away with a legacy mesh clinging hydro-poly which roughly covers the lake.

By far the easiest program to do this is SBuilderX.

Where is the lake?

[Tejal Bernardo]

You have to get rid of the lake and then to make your own lake with the correct data. FsxKml could help too.

[Timmo]

It's because hydro-polygons (i.e Lakes, Rivers, sea) in FSX are 'Z aware' meaning that they know their height AND they take precedence over your DTM (i.e. it's not the default DTM data that is causing the problem, its the default hydro polygons)

So, as mentioned, exclude the default lake and digitise a new one obtaining the new lake height from your DTM at the shore line. For FSX hydro polys of this type, each vertex needs to know it's height (which will all be the same) and slope (which will be 0 for both X and Y).