/**
* Comparing on geohash ensures that nearby nodes will be close
* to each other in the list.
*/
static int
circ_node_compare(const void* v1, const void* v2)
{
POINT2D p1, p2;
unsigned int u1, u2;
CIRC_NODE *c1 = (CIRC_NODE*)v1;
CIRC_NODE *c2 = (CIRC_NODE*)v2;
p1.x = rad2deg((c1->center).lon);
p1.y = rad2deg((c1->center).lat);
p2.x = rad2deg((c2->center).lon);
p2.y = rad2deg((c2->center).lat);
u1 = geohash_point_as_int(&p1);
u2 = geohash_point_as_int(&p2);
if ( u1 < u2 ) return -1;
if ( u1 > u2 ) return 1;
return 0;
}
static void test_geohash_point_as_int(void)
{
unsigned int gh;
POINT2D p;
unsigned long long rs;
p.x = 50; p.y = 35;
gh = geohash_point_as_int(&p);
rs = 3440103613;
CU_ASSERT_EQUAL(gh, rs);
p.x = 140; p.y = 45;
gh = geohash_point_as_int(&p);
rs = 3982480893;
CU_ASSERT_EQUAL(gh, rs);
p.x = 140; p.y = 55;
gh = geohash_point_as_int(&p);
rs = 4166944232;
CU_ASSERT_EQUAL(gh, rs);
}
