75 lines
2.2 KiB
Text
75 lines
2.2 KiB
Text
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FG Scenery Tools README
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=======================
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Contained here-in are the FG scenery creation tools. These can be
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used to convert 3 arcsec ASCII format DEM files and 30 arcsec binary
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format DEM files into Flight Gear scenery.
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Eventually these tools will expand to support insertion of airports,
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roads, rivers, lakes, etc.
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Building the Tools
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==================
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These tools are compiled and tested under Linux. I'm all for
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portability, but I just haven't been as motivated to port these tools,
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since scenery creation is less of a general need ... especially at
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this stage. However, if anyone wants to work on porting to other
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platforms, I will be happy to incorporate patches.
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The process for building these tools is very similar to building the
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main FG source code.
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1. Set the FG_ROOT, FG_ROOT_SRC, and FG_ROOT_LIB environment
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variables.
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2. Run ``make depend''
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3. Run ``make clean''
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4. Run ``make''
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3 Arcsec ASCII DEM files
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========================
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Data files for the USA are available in this format from:
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http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html
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To generate FG scenery from one of these dem files, run:
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./process-dem.pl <error-tolerance-squared> dem-file-1 [ dem-file-2 ...]
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You can vary the error tolerance to control the level of detail (and
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size) of the resulting scenery. Note, you must specify the error
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tolerance squared. So, if you wish to allow up to a 10 meter error
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margin (very high level of detail) you would specify a value of 100.
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If you desire an error tolerance of 200 meters (medium detail level)
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you would specify a value of 40000.
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The process-dem.pl script will automatically dump the resulting .obj
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files in the proper directory tree.
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30 Arcsec Binary DEM files
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==========================
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These data files have world wide coverage and are available from:
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http://edcwww.cr.usgs.gov/landdaac/gtopo30/gtopo30.html
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To process these data files, you must first run:
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DemRaw2Ascii/raw2ascii <input_file_basename> <output_dir>
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For example:
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DemRaw2Ascii/raw2ascii /tmp/W020N90 asciidems/
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This will create ASCII DEM files for each 1 degree x 1 degree area in
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the specified output dir.
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Then, you can take these ascii dem files and feed them through the
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same procedure you use with the 3 arcsec dem files.
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