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Holger

converting DEM data-assistance required

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I am new to creating Mesh fror FS2002. I have read quite widely on the subject, starting with the Microsoft SDK, but much is still unclear to me.What I really need to get hold of is a tutorial which sets out the steps in order, from beginning to end in simple language.I have gained a reasonable idea of what is involved, so I set about acquiring DEM data from official sources. What I got for my area of interest was two sets of DEM data, one for 200m resolution and one for 50m. The area I wish to cover is not very large, so to use the higher resolution might not impact on frame rates once compiled and installed in FS2002 (or will it? or does it make a difference?)Well, to start, the DEM data is in ASCII format, and I reproduce the header and a few lines of data here as follows: LO(CM) = 19 BPQ1 = 93300 3764100 BPQ3 = 46100 3707700 DEMRES = 200 XEXTENT = 282 YEXTENT = 236 93200.00 3764000.00 0 93200.00 3763800.00 0 93200.00 3763600.00 0 93200.00 3763400.00 0 93200.00 3763200.00 0I haven't got a clue how to interpret and use this other than that it must be converted to start off so that it may be used as per the SDK.CAn anybody PLEASE assist by interpreting the data (or header) by telling me what 'format" this is in, and what conversion software I should employ to render it useful for FS2002 use. I presume the conversion program might use DOS routines, so in anticipation, may I also ask the syntax to be used for the appropriate program.To whoever replies and assists me, a BIG THANK YOU in anticipation.

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Hello sunstream:well, I can start the guidance by interpreting the header of your file - that's the easy part ;-)LO(CM) = 19 -> don't know, probably some identifier - err, good start :-)BPQ1 = 93300 3764100 -> NW corner of the data, probably in UTM (Universal Transversal Mercartor) format but could be in some other similar projection, converting latitude/longitude into a rectangular grid measured in meters. The first number is Northing, the second one Easting (i.e., distances from the reference latitude and meridian). It is important to know what the projection and reference points are but any official data should include that information.BPQ3 = 46100 3707700 -> SE corner of the data, as aboveDEMRES = 200 -> horizontal resolution, i.e., 200 metersXEXTENT = 282 -> number of columnsYEXTENT = 236 -> number of rows93200.00 3764000.00 0 -> the data in triplets: UTM northing, UTM easting, elevation (obviously, there's some ocean in your elevation model, as indicated by the zeros)93200.00 3763800.00 093200.00 3763600.00 093200.00 3763400.00 093200.00 3763200.00 0As for the conversion process, I'll pass the hat. I am fortunate to have (commercial) Geographic Information System (GIS) software on my system but I'm sure there are small utilities out there somewhere that would take this very common format and turn it into the .bsq format required by the Terrain SDK. If not, I suggest you download and get to know the freeware MicroDEM software: http://www.usna.edu/Users/oceano/pguth/website/microdem.htm. It will import almost any data format, and, in combination with John Child's mdem2bsq.zip utility (available on his "Digital Terrain Modeling and Mapping Journal" web pages at http://www.terrainmap.com/) you'll be able to complete your task.Hope that helps. Welcome to "The Club".Cheers, HolgerP.S.: If you happen to download my British Columbia terrain meshes you'll find a pretty detailed documentation on how I got my source data to work. And I'm sure you've seen Steve Greenwood's excellent resources at http://www.fs-traveler.com/fs-traveler.html.

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