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Guest taalspin

FSDEM not working for me

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Have been reading with interest on how well FSDEM works for creating scenery mesh files. However, that has not been my case.I downloaded N47W123.hgt (the 1 arcsecond) and chose the load single HGT. After it unzips and loads the file and I click the make BGL file it informs me it has voids, since this area is coastal, there are numerous areas that change due to the tides. So I tried both ways and I also choose Lod 10 level: (1)ignoring the voids and making a 39KB bgl file; (2) Not choosing or selecting any specific area but making a file that interpolated the entire block (1degree by 1degree) making a 1KB bgl file. So obviously I am not doing something right. When it completed the interpolation, there were no orange/red areas, they had all been changed to blue. The first scenery file didn't seem to change the contours from the fs2002 default. Any help would be appreciated.Taalsping

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Hi Taalsping,I have successfully created a valid BGL file (N48W123_N47W122.bgl, LOD10, 2765KB in size) from N47W123.hgt (SRTM-1).Ensure you have the latest version of FSDEM (1.1).You should not leave voids in the mesh, unless you plan to merge the mesh further, using Resample or another tool. Note that remaining voids are possible after the interpolation process because the IDW interpolation algorithm implemented in FSDEM doesn't fill voids located outside the search (neighborhood) radius given as parameter. So after the interpolation, you should use the Mesh Info button to check for the number of remaining voids. This is the best way to check for voids, because sometimes there are still a few sparse voids not easily visible. Anyway, FSDEM 1.1 always scans the mesh and counts the number of voids when the user access the Create BGL menu, and notifies the user for any remaining void.I've tested the interpolation process of N47W123.hgt, using the default radius (70) of FSDEM 1.1, and found some remaining void holes - large holes - BTW. In this case, you may Undo the interpolation and then increase the neighborhood radius and repeat the process, or fill the remaining voids with the filling tools (as I did in my test), or even consider merging with a lower resolution mesh. Well, that are design decisions.By the way, the tile N47W123.hgt is in USA, isn't it? Well, I don't know about the project you are developing and your specific requirements, but you know that, sometimes, SRTM is not the best choice for U.S. areas, i.e., there are another void-free DEM data available for this area (e.g. DTED). Regards,Emerson

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Emerson,Thank-you for your response. After writing my post, I went back to your program, determined to make it work. For some reason, initially I couldn't seem to make a valid BGL file so I placed my SRTM files into the same folder as the FSDEM program. And this seemed to help but I can't explain why.Watching the Resampling process, it seems like your program takes the Zipped SRTM file and places it into the FSDEM temp folder, labeling this as the source and then compiles the BGL. I am not a programmer so I may not have it real "correct" but anyway I figured out using the interpolation process first, seemed to work better. Originally, I tried selecting the entire "chunck" and use the filling tool and then select "make bgl" which did provide a file but one that was unworkable.Working on this particular area also provided another challenge; trying to determine which red areas are glitches and which are legitimate lakes. And yes, there are some pretty big holes that are centered in the Olympic Mountains (this area is located in the northwest part of the state of Wahington, US). However, to sum up. By interpolating various sections at the default values and increasing them to around 80 mile radius for the biggest "sinkholes" did provide a very interesting and much more detailed mesh than Gates' default variety. So some mesh was actually created using your program (and having not been able to use the Blackart program because it was way beyond me; I think that one requires a guide unless you are already some kind of wizard). So I'll probably have more questions, later.Yours truly,Taalspin

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