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#ifndef __FLAG_H__
#define __FLAG_H__
/* flag.[ch] is a set of routines which will set up an array of bits
** that allow the programmer to "flag" cells in a raster map.
**
** FLAG *
** flag_create(nrows,ncols)
** int nrows, ncols;
** opens the structure flag.
** The flag structure will be a two dimensional array of bits the
** size of nrows by ncols. Will initialize flags to zero (unset).
**
** flag_destroy(flags)
** FLAG *flags;
** closes flags and gives the memory back to the system.
**
** flag_clear_all(flags)
** FLAG *flags;
** sets all values in flags to zero.
**
** flag_unset(flags, row, col)
** FLAG *flags;
** int row, col;
** sets the value of (row, col) in flags to zero.
**
** flag_set(flags, row, col)
** FLAG *flags;
** int row, col;
** will set the value of (row, col) in flags to one.
**
** int
** flag_get(flags, row, col)
** FLAG *flags;
** int row, col;
** returns the value in flags that is at (row, col).
**
** idea by Michael Shapiro
** code by Chuck Ehlschlaeger
** April 03, 1989
*/
#define FLAG struct _flagsss_
FLAG
{
int nrows, ncols, leng;
unsigned char **array;
};
#define FLAG_UNSET(flags, row, col) \
(flags)->array[(row)][(col) >> 3] &= ~(1 << ((col)&7))
#define FLAG_SET(flags, row, col) \
(flags)->array[(row)][(col) >> 3] |= (1 << ((col)&7))
#define FLAG_GET(flags, row, col) \
(flags)->array[(row)][(col) >> 3] & (1 << ((col)&7))
/* flag.c */
FLAG *flag_create(int, int);
int flag_destroy(FLAG *);
int flag_clear_all(FLAG *);
#endif /* __FLAG_H__ */
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