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/****************************************************************************
*
* MODULE: r.buffer
*
* AUTHOR(S): Michael Shapiro - CERL
*
* PURPOSE: This program creates distance zones from non-zero
* cells in a grid layer. Distances are specified in
* meters (on the command-line). Window does not have to
* have square cells. Works both for planimetric
* (UTM, State Plane) and lat-long.
*
* COPYRIGHT: (C) 2005 by the GRASS Development Team
*
* This program is free software under the GNU General Public
* License (>=v2). Read the file COPYING that comes with GRASS
* for details.
*
****************************************************************************/
#include "distance.h"
#include <grass/gis.h>
int init_grass(void)
{
double a, e2;
double factor;
G_get_set_window(&window);
if (window.proj == PROJECTION_LL) {
G_get_ellipsoid_parameters(&a, &e2);
G_begin_geodesic_distance(a, e2);
wrap_ncols =
(360.0 - (window.east - window.west)) / window.ew_res + 1.1;
/* add 1.1 instead of 1 to insure that we round up, not down */
}
else {
wrap_ncols = 0;
factor = G_database_units_to_meters_factor();
if (factor <= 0.0)
factor = 1.0;
meters_to_grid = 1.0 / factor;
}
return 0;
}
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