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ATL_ELEVATION_DELETE(3T)         ATL FUNCTIONS         ATL_ELEVATION_DELETE(3T)



NAME
        atl_elevation_delete - delete elevations in Aviator terrain data files

SYNOPSIS
        #include <atl.h>

        int atl_elevation_delete(long_00, lat_00, long_0c, lat_0c,
                                 long_r0, lat_r0, long_rc, lat_rc)
        double long_00, lat_00, long_0c, lat_0c;
        double long_00, lat_r0, long_rc, lat_rc;

DESCRIPTION
        atl_elevation_delete() deletes elevations from the data files used by
        Aviator.  The data files have filenames of ???_??? where ? is a
        number.

        long_00 and lat_00, long_0c and lat_0c, long_r0 and lat_r0, and
        long_rc and lat_rc represent the longitudes and latitudes of the
        locations on the globe of the area bounding box where the elevations
        will be deleted.  All longitudes are measured in degrees from the
        from the Meridian of Greenwich and all latitudes are measured in
        degrees from Equator.

        atl_elevation_delete() allows sections of elevation data to be removed
        so that they may be replaced with other elevations to create a mosaic
        (eg. removing bad data).  Calls to atl_elevation_delete() can be
        intermixed with calls to atl_elevation(), but can only be called
        before atl_elevation_post().

RETURN VALUES
        atl_elevation_delete() returns:
        0       on success.
        -1      on failure.

FILES
        /usr/games/aviator/atl/h/atl.h
        /usr/games/aviator/atl/lib/libatl.a
        /usr/games/aviator/passwords
        /usr/games/aviator/terrain/???_???

ENVIRONMENT
        The environment variable AVIATOR_HOME points to the home directory for
        aviator, if it is other than /usr/games/aviator.  AVIATOR_PASSWORDS
        points to the file that contains the password file passwords, if it is
        other than /usr/games/aviator/passwords or ${AVIATOR_HOME}/passwords.
        passwords contains the password needed to use atl_color().  The
        following are examples of how to set AVIATOR_HOME and
        AVIATOR_PASSWORDS:

                setenv AVIATOR_HOME      /home/bigdisk/aviator
                setenv AVIATOR_PASSWORDS /home/bigdisk/aviator/passwords

SEE ALSO
        atl_elevation(3T), atl_elevation_post(3T), atl_mksparse(1T),
        passwords(5A)

NOTES
        atl_elevation_delete() does not reduce the size of the data files that
        it operates on.  If atl_elevation_delete() is used, run atl_mksparse
        on the data files to make them as small as possible.



ATL Release 1.8         Last change: 25 December 1991