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ShapeFile Projection Conversion

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FSXI saw the message sequence on the need to convert from NAD83 to WGS84 or shp2vec will not work. I believe that the road file I have is NAD83 since everything from that source is NAD83. I can look and alter the files contents with a program called MapEdit. However, it will not save in a projection different from the original. ERDAS Viewfinder does not read Shape files. Global Mapper, that does everything, costs $270!! Is there a program that will re-project shape files from NAD83 to WGS84?Dick Boley near 5G8


regards,

Dick near Pittsburgh, USA

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Hi Dick,you don't really need to re-project NAD83 to WGS84 because the two *datums* are virtually identical. See, e.g., http://www.mentorsoftwareinc.com/resource/Nad83.htmHowever, most data files that use NAD83 are in UTM *projection* - http://www.colorado.edu/geography/gcraft/n...s/coordsys.html - rather than the required geographic lat/long "projection" FS requires. If that's the case then you need to re-project from UTM to geographic.I believe that the free fGIS does this - http://www.forestpal.com/fgis.html - but there have been several discusssions in this forum about these kinds of utilities so try the Search function.Cheers, Holger

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I have loaded and used the fGIS utility program. I also found Luiz's tutorial on creating an Exclude with the program. THAT SHOULD BE PINNED.I now see that you need to modify the DBF file with fGIS to get the UUID and GUID in place. I follow the creation of a new element/layer ok. However, I am importing a roads Shapefile (lines). It seems that fGIS needs to select lines to attach GUIDs & UUIDs. Logically I want to select all of the lines and add the GUID & UUID to them all. However, I have been unable to figure out how to select all of the lines at once.??? Probably a dumb mental blockage. Luiz's tutorial reveals the need (or I think it does) to enter GUID/UUID into the DBF file. This was not clear to me from the SDK.Dick Boley


regards,

Dick near Pittsburgh, USA

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This is probably asking for the obvious but -- I cannot find a way to add a UUID, or GUID, value to all of the records in my shapefile at once using DBF_Explorer. I can add the UUID & GUID column ok and make an entry ok but from my perspective there seems to be no way to do a mass change. I have 43139 records in the file representing the roads of a county.All this is based upon the assumption that each record must have a UUID and GUID value.Dick Boley>Hi Dick.>>For quickly altering the DBF files, I suggest using DBF>Explorer (freeware ):>>http://www.pablosoftwaresolutions.com/html/dbf_explorer.html>>Dick


regards,

Dick near Pittsburgh, USA

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Hi Dick.I get it now. :)You might try Open Office. I know this is heresy for a Microsoft project, but I believe the spreadsheet will handle a huge amount of data, and imports/exports DB3 files.http://www.openoffice.org/index.htmlEDITED>>>OpenOffice Calc does indeed import and export DBF files. You can add columns, cut and paste, fill selected areas, etc... I added a comment line:http://forums.avsim.net/user_files/162399.jpgYou can add fields to your shapefile DBF that are not used by Shp2Vec, and the compiler will ignore them... handy for adding comments.Dick

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Yes, Open Office does work and loads up 43,139 records "eventually". I added the UUID and GUID fields and filled them with the IDs. However, I also looked at an example RDX file and in there are only the GUID and UUID columns so I can reduce the file size by dropping the other columns. Also, no title line. The interesting thing that I see is that all of the GUIDs are not the same. I assume this provided different textures/size for various roads. The confusing aspect is that the UUIDs were also different. If each record needs its own UUID that is a lot of typing.Part of an example road file from SDK:http://forums.avsim.net/user_files/162400.jpg


regards,

Dick near Pittsburgh, USA

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Hi,I use Microsoft Access to manipulate those DBF files. I also created a module inside MS Access to assign unique UUID for each record. As for the GUID, I imported Luis' Excel file into MS Access and created a bunch of queries to do all the required changes of textures.That's your best bet...Regards,Juan

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Hi Dick.Apparently in the source, each segment is given a Uuid. Nothing wrong with that at all. The Uuid is not used in FSX, but is needed for shp2vec. The Uuids can be sequentially numbered. The Guids are found in the "Textures" of the terrain.cfg file.Dick

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Juan,I believe that Access costs about $130. However, there is probably a run-time module. If so would you be able to "dress up" your Access program to be used to created suitable files for Shp2Vec ?Dick Boley


regards,

Dick near Pittsburgh, USA

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Ok on GUIDs used for specific texturing of various Shapefile elements. However, while somewhat implied, is there a definitive answer on the need for a unique UUID for each element in a Shapefile DBF file? The SDK does not seem to specifically address this except if you draw the conclusion that unique UUIDs are needed. If so I need to put a +1 in the spreadsheet.Thanks,Dick Boley


regards,

Dick near Pittsburgh, USA

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The thing I would be careful of, is that if you are using several different shapefiles to feed to shp2vec it might not be a good idea to have identical UUIDs among the different source shapefile features. So far I haven't really gone into any production mode with shapefiles. I'm not sure what happens with dozens or more features in a single shapefile, and many shapefiles.scott s..

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Well, I finally was able to take a County road Shapefile and see the roads in FSX. First - all of the UUIDs were the sameSecond - all of the GUIDs were the same. Set for 2 lane asphalt.Third - eliminating all of the descriptive columns (other than UUID & GUID) in the DBF file caused no harm and reduced file size and perhaps processing.I used the Open Office spreadsheet to make the DBF changes. I tried Excel but my file size (43000+ records) were beyond it. I used fGIS to clip out a small section of the file for testing. Once I failed to include the XML file and TMFViewer took the BGL file ok but displayed nothing. A few minutes were consumed on that mistake.The downside is that all of my roads in this area are now 2-lane asphalt. Since they are not freeways there is no traffic, which my miserable system is incapable of anyhow. There seems to be no misalignment of the FSX and mapped roads. That is, I do not see dual images of a road offset by a few feet/meters. Need further viewing to see if that is correct. As in some cases, FSX may take the latest BGL with vector info and use it ignoring lower priority BGLs.Thanks to all for their help. The process was lengthened by the two-thirds explanation in the SDK and the need to find which tools to use. As is often the case the process is simple but the route to it is torturous.Regards,Dick Boley


regards,

Dick near Pittsburgh, USA

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