[Xastir] FAA sectionals

[Doug Alwine]

On 03/24/2011 07:56 PM, Tom Russo wrote:
> On Thu, Mar 24, 2011 at 07:31:04PM -0400, we recorded a bogon-computron collision of the<AB1GW at alwine.us>  flavor, containing:
>>
>> Hi,
>>
>> After some struggle I finally have xastir working!  It works fine with
>> tiger maps and USGS topo maps in GEOtiff format.  It will also display
>> FAA sectional charts (also in geotiff) but to get things in the right
>> place I need to convert them from the Lambert Conical Projection to
>> something that xastir can use.
>>
>> After compiling xastir, soundmodem, and gdal from source and struggling
>> to get things working so far, this seems like it ought to be fairly
>> easy,  but I cannot figure out how to use gdalwarp to solve my problem.
>
> It's not hard, assuming you got gdal installed (which might have been easy if
> your system has gdal in its package management system).
>
>> From README.MAPS:
>      GeoTIFF files in certain projections need special processing:
>
>        Not all geotiff files available on the net are usable directly in
>        xastir.  Some of them are in projections that xastir can't use
>        properly, and others are missing all of the metadata information that
>        is needed to work out how to convert them to Lat/Lon unprojected rasters.
>        If you encounter a geotiff file that has the correct tags, but is
>        in some projection other than UTM, you can convert that file to a
>        lat/lon raster if you have gdal installed.  Simply run the following
>        command:
>          gdalwarp -t_srs EPSG:4326 original_raster.tif usable_raster.tif
>
>        This will warp the geotiff file "original raster.tif" from
>        whatever projection it was in into an unprojected lat/lon raster
>        "usable_raster.tif" that can be directly read into xastir.
>
>
> If you tried that and it didn't do the trick, then what went wrong?
>

Well, I saw that in the README file about a week ago, and when I tried 
it I got a completely black area where the map was supposed to be.  I 
assumed that I did something wrong.  However,  I just now tried it again 
and it worked.  Poor typing skills perhaps?  I feel kinda stupid now.

Any way, thanks so very much for the help!

Doug