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/*
****************************************************************************
*
* MODULE: Vector library
*
* AUTHOR(S): Radim Blazek
*
* PURPOSE: Lower level functions for reading/writing/manipulating vectors.
*
* COPYRIGHT: (C) 2001 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 <stdlib.h>
#include <grass/Vect.h>
/*
* dig_line_box ()
* set box to points extent
*/
int dig_line_box(struct line_pnts *Points, BOUND_BOX * Box)
{
int i;
if (Points->n_points <= 0) {
Box->N = 0;
Box->S = 0;
Box->E = 0;
Box->W = 0;
Box->T = 0;
Box->B = 0;
return 0;
}
Box->E = Points->x[0];
Box->W = Points->x[0];
Box->N = Points->y[0];
Box->S = Points->y[0];
Box->T = Points->z[0];
Box->B = Points->z[0];
for (i = 1; i < Points->n_points; i++) {
if (Points->x[i] > Box->E)
Box->E = Points->x[i];
else if (Points->x[i] < Box->W)
Box->W = Points->x[i];
if (Points->y[i] > Box->N)
Box->N = Points->y[i];
else if (Points->y[i] < Box->S)
Box->S = Points->y[i];
if (Points->z[i] > Box->T)
Box->T = Points->z[i];
else if (Points->z[i] < Box->B)
Box->B = Points->z[i];
}
return 1;
}
/*
* dig_box_copy ()
* Copy B to A.
*/
int dig_box_copy(BOUND_BOX * A, BOUND_BOX * B)
{
A->N = B->N;
A->S = B->S;
A->E = B->E;
A->W = B->W;
A->T = B->T;
A->B = B->B;
return 1;
}
/*
* dig_box_extend ()
* Extend A by B.
*/
int dig_box_extend(BOUND_BOX * A, BOUND_BOX * B)
{
if (B->N > A->N)
A->N = B->N;
if (B->S < A->S)
A->S = B->S;
if (B->E > A->E)
A->E = B->E;
if (B->W < A->W)
A->W = B->W;
if (B->T > A->T)
A->T = B->T;
if (B->B < A->B)
A->B = B->B;
return 1;
}
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