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Guest sgreenwood

desperately need some help (newbie)

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I am a newbie at creating mesh. Normally I am myself pretty good at figuring stuff out on my own, but in this case it seems like following the directions has only led to frustration.I am trying to create my first mesh terrain. I have looked at tutorials, downloaded tools, and so far my results have been nothing useful. Here is what I've done so far.I have downloaded 7.5-minute swatchs of 10m data from the MapMart.com, and they are in SDTS format (free of charge).My next step as I understand it, is to convert the data to a format that the FS2002 SDK resample tool can understand... binary 16-bit integer data. In order to do this, I downloaded the read_dem.exe program as suggested in the SDK documentation. The read_dem tool is interesting. When I feed it any SDTS file, it produces an output and header file, but also gives the following message: "Warning - first file in the tar archive is not SDTS catalog file -- may be unusable."I have checked the tar archive, and the first file is in fact a xxxxCATD.DDF file, which is the catalog file. I don't know why it has this problem, but I forged ahead anyway hoping it wouldn't matter.Next was creating my .INF file. I have only attempted to do this for a single file. I used the information from the header information to get this correct.Here is my INF file (please note that I have put semi-colon comments in to explain things):[Destination]LOD = 10DestDir = "E:Terrain"DestBaseFileName = "LandronPeak_NM"UseSourceDimensions = 1[source]Type = ElevS16LSBSourceDir = "E:Terrain"SourceFile = "output"Lat = 34.375 ; 34 22' 30" NLon = -107.25 ; 107 15' 0" WNumOfCellsPerLine = 1180 ; taken from the header informationNumOfLines = 1411 ; same; in the next line, 7.5 minutes is 12.5 percent of 1 degree. so using .125CellXdimensionDeg = .000105932 ; .125/1180CellYdimensionDeg = .000088589 ; .125/1411ScaleInMeters = 1.0I THINK I got all this right. However, when I run the resample tool against the .INF file, it creates a .BGL file of only 512 bytes.I have been over and over this and I cannot see what I'm doing wrong. Has anyone experienced anything similar or can point me to where I have fouled things up?Thanks,Allen

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Hi Allen,The SDK is not as helpful as it might be.Your single 7.5 minute source data quadrant does not completely fill a Resample LOD10 quadrant at those coordinates - Resample will not create partial LOD quadrants, so you get an empty bgl file. You need to increase the LOD to at least 11 or use data for a larger area.Although much less significant, you should adjust your calculations as follows:CellXdimensionDeg = .125/(1180-1)CellYdimensionDeg = .125/(1411-1)e.g.: 1180 data points have 1179 spaces between them; the dimension of this (CellX) spacing is what is needed to determine the positions of the data.I am not sure about the rest of your process, but the LOD issue is a show-stopper. I have some additional information available at www.fs-traveler.comGood luck,Steve

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