int geohash_get_neighbors(const GeoHashBits* hash, GeoHashNeighbors* neighbors)
{
neighbors->east = *hash;
neighbors->west = *hash;
neighbors->north = *hash;
neighbors->south = *hash;
neighbors->south_east = *hash;
neighbors->south_west = *hash;
neighbors->north_east = *hash;
neighbors->north_west = *hash;
geohash_move_x(&neighbors->east, 1);
geohash_move_y(&neighbors->east, 0);
geohash_move_x(&neighbors->west, -1);
geohash_move_y(&neighbors->west, 0);
geohash_move_x(&neighbors->south, 0);
geohash_move_y(&neighbors->south, -1);
geohash_move_x(&neighbors->north, 0);
geohash_move_y(&neighbors->north, 1);
geohash_move_x(&neighbors->north_west, -1);
geohash_move_y(&neighbors->north_west, 1);
geohash_move_x(&neighbors->north_east, 1);
geohash_move_y(&neighbors->north_east, 1);
geohash_move_x(&neighbors->south_east, 1);
geohash_move_y(&neighbors->south_east, -1);
geohash_move_x(&neighbors->south_west, -1);
geohash_move_y(&neighbors->south_west, -1);
return 0;
}
int geohash_get_neighbor(const GeoHashBits* hash, GeoDirection direction, GeoHashBits* neighbor)
{
if (NULL == neighbor)
{
return -1;
}
*neighbor = *hash;
switch (direction)
{
case GEOHASH_NORTH:
{
geohash_move_x(neighbor, 0);
geohash_move_y(neighbor, 1);
break;
}
case GEOHASH_SOUTH:
{
geohash_move_x(neighbor, 0);
geohash_move_y(neighbor, -1);
break;
}
case GEOHASH_EAST:
{
geohash_move_x(neighbor, 1);
geohash_move_y(neighbor, 0);
break;
}
case GEOHASH_WEST:
{
geohash_move_x(neighbor, -1);
geohash_move_y(neighbor, 0);
break;
}
case GEOHASH_SOUTH_WEST:
{
geohash_move_x(neighbor, -1);
geohash_move_y(neighbor, -1);
break;
}
case GEOHASH_SOUTH_EAST:
{
geohash_move_x(neighbor, 1);
geohash_move_y(neighbor, -1);
break;
}
case GEOHASH_NORT_WEST:
{
geohash_move_x(neighbor, -1);
geohash_move_y(neighbor, 1);
break;
}
case GEOHASH_NORT_EAST:
{
geohash_move_x(neighbor, 1);
geohash_move_y(neighbor, 1);
break;
}
default:
{
return -1;
}
}
return 0;
}
