PostGIS  2.5.0dev-r@@SVN_REVISION@@
static double circ_tree_distance_tree_internal ( const CIRC_NODE n1,
const CIRC_NODE n2,
double  threshold,
double *  min_dist,
double *  max_dist,
GEOGRAPHIC_POINT closest1,
GEOGRAPHIC_POINT closest2 
)
static

Definition at line 605 of file lwgeodetic_tree.c.

References circ_node_is_leaf(), circ_node_max_distance(), circ_node_min_distance(), circ_tree_contains_point(), circ_tree_get_point(), edge_distance_to_edge(), edge_distance_to_point(), edge_intersection(), edge_intersects(), circ_node::edge_num, GEOGRAPHIC_EDGE::end, FP_MIN, geog2cart(), geographic_point_init(), circ_node::geom_type, LWDEBUG, LWDEBUGF, lwtype_is_collection(), circ_node::nodes, circ_node::num_nodes, circ_node::p1, circ_node::p2, POLYGONTYPE, circ_node::pt_outside, sphere_distance(), GEOGRAPHIC_EDGE::start, POINT2D::x, and POINT2D::y.

Referenced by circ_tree_distance_tree().

606 {
607  double max;
608  double d, d_min;
609  uint32_t i;
610 
611  LWDEBUGF(4, "entered, min_dist=%.8g max_dist=%.8g, type1=%d, type2=%d", *min_dist, *max_dist, n1->geom_type, n2->geom_type);
612 /*
613  circ_tree_print(n1, 0);
614  circ_tree_print(n2, 0);
615 */
616 
617  /* Short circuit if we've already hit the minimum */
618  if( *min_dist < threshold || *min_dist == 0.0 )
619  return *min_dist;
620 
621  /* If your minimum is greater than anyone's maximum, you can't hold the winner */
622  if( circ_node_min_distance(n1, n2) > *max_dist )
623  {
624  LWDEBUGF(4, "pruning pair %p, %p", n1, n2);
625  return FLT_MAX;
626  }
627 
628  /* If your maximum is a new low, we'll use that as our new global tolerance */
629  max = circ_node_max_distance(n1, n2);
630  LWDEBUGF(5, "max %.8g", max);
631  if( max < *max_dist )
632  *max_dist = max;
633 
634  /* Polygon on one side, primitive type on the other. Check for point-in-polygon */
635  /* short circuit. */
636  if ( n1->geom_type == POLYGONTYPE && n2->geom_type && ! lwtype_is_collection(n2->geom_type) )
637  {
638  POINT2D pt;
639  circ_tree_get_point(n2, &pt);
640  LWDEBUGF(4, "n1 is polygon, testing if contains (%.5g,%.5g)", pt.x, pt.y);
641  if ( circ_tree_contains_point(n1, &pt, &(n1->pt_outside), NULL) )
642  {
643  LWDEBUG(4, "it does");
644  *min_dist = 0.0;
645  geographic_point_init(pt.x, pt.y, closest1);
646  geographic_point_init(pt.x, pt.y, closest2);
647  return *min_dist;
648  }
649  }
650  /* Polygon on one side, primitive type on the other. Check for point-in-polygon */
651  /* short circuit. */
652  if ( n2->geom_type == POLYGONTYPE && n1->geom_type && ! lwtype_is_collection(n1->geom_type) )
653  {
654  POINT2D pt;
655  circ_tree_get_point(n1, &pt);
656  LWDEBUGF(4, "n2 is polygon, testing if contains (%.5g,%.5g)", pt.x, pt.y);
657  if ( circ_tree_contains_point(n2, &pt, &(n2->pt_outside), NULL) )
658  {
659  LWDEBUG(4, "it does");
660  geographic_point_init(pt.x, pt.y, closest1);
661  geographic_point_init(pt.x, pt.y, closest2);
662  *min_dist = 0.0;
663  return *min_dist;
664  }
665  }
666 
667  /* Both leaf nodes, do a real distance calculation */
668  if( circ_node_is_leaf(n1) && circ_node_is_leaf(n2) )
669  {
670  double d;
671  GEOGRAPHIC_POINT close1, close2;
672  LWDEBUGF(4, "testing leaf pair [%d], [%d]", n1->edge_num, n2->edge_num);
673  /* One of the nodes is a point */
674  if ( n1->p1 == n1->p2 || n2->p1 == n2->p2 )
675  {
676  GEOGRAPHIC_EDGE e;
677  GEOGRAPHIC_POINT gp1, gp2;
678 
679  /* Both nodes are points! */
680  if ( n1->p1 == n1->p2 && n2->p1 == n2->p2 )
681  {
682  geographic_point_init(n1->p1->x, n1->p1->y, &gp1);
683  geographic_point_init(n2->p1->x, n2->p1->y, &gp2);
684  close1 = gp1; close2 = gp2;
685  d = sphere_distance(&gp1, &gp2);
686  }
687  /* Node 1 is a point */
688  else if ( n1->p1 == n1->p2 )
689  {
690  geographic_point_init(n1->p1->x, n1->p1->y, &gp1);
691  geographic_point_init(n2->p1->x, n2->p1->y, &(e.start));
692  geographic_point_init(n2->p2->x, n2->p2->y, &(e.end));
693  close1 = gp1;
694  d = edge_distance_to_point(&e, &gp1, &close2);
695  }
696  /* Node 2 is a point */
697  else
698  {
699  geographic_point_init(n2->p1->x, n2->p1->y, &gp1);
700  geographic_point_init(n1->p1->x, n1->p1->y, &(e.start));
701  geographic_point_init(n1->p2->x, n1->p2->y, &(e.end));
702  close1 = gp1;
703  d = edge_distance_to_point(&e, &gp1, &close2);
704  }
705  LWDEBUGF(4, " got distance %g", d);
706  }
707  /* Both nodes are edges */
708  else
709  {
710  GEOGRAPHIC_EDGE e1, e2;
712  POINT3D A1, A2, B1, B2;
713  geographic_point_init(n1->p1->x, n1->p1->y, &(e1.start));
714  geographic_point_init(n1->p2->x, n1->p2->y, &(e1.end));
715  geographic_point_init(n2->p1->x, n2->p1->y, &(e2.start));
716  geographic_point_init(n2->p2->x, n2->p2->y, &(e2.end));
717  geog2cart(&(e1.start), &A1);
718  geog2cart(&(e1.end), &A2);
719  geog2cart(&(e2.start), &B1);
720  geog2cart(&(e2.end), &B2);
721  if ( edge_intersects(&A1, &A2, &B1, &B2) )
722  {
723  d = 0.0;
724  edge_intersection(&e1, &e2, &g);
725  close1 = close2 = g;
726  }
727  else
728  {
729  d = edge_distance_to_edge(&e1, &e2, &close1, &close2);
730  }
731  LWDEBUGF(4, "edge_distance_to_edge returned %g", d);
732  }
733  if ( d < *min_dist )
734  {
735  *min_dist = d;
736  *closest1 = close1;
737  *closest2 = close2;
738  }
739  return d;
740  }
741  else
742  {
743  d_min = FLT_MAX;
744  /* Drive the recursion into the COLLECTION types first so we end up with */
745  /* pairings of primitive geometries that can be forced into the point-in-polygon */
746  /* tests above. */
747  if ( n1->geom_type && lwtype_is_collection(n1->geom_type) )
748  {
749  for ( i = 0; i < n1->num_nodes; i++ )
750  {
751  d = circ_tree_distance_tree_internal(n1->nodes[i], n2, threshold, min_dist, max_dist, closest1, closest2);
752  d_min = FP_MIN(d_min, d);
753  }
754  }
755  else if ( n2->geom_type && lwtype_is_collection(n2->geom_type) )
756  {
757  for ( i = 0; i < n2->num_nodes; i++ )
758  {
759  d = circ_tree_distance_tree_internal(n1, n2->nodes[i], threshold, min_dist, max_dist, closest1, closest2);
760  d_min = FP_MIN(d_min, d);
761  }
762  }
763  else if ( ! circ_node_is_leaf(n1) )
764  {
765  for ( i = 0; i < n1->num_nodes; i++ )
766  {
767  d = circ_tree_distance_tree_internal(n1->nodes[i], n2, threshold, min_dist, max_dist, closest1, closest2);
768  d_min = FP_MIN(d_min, d);
769  }
770  }
771  else if ( ! circ_node_is_leaf(n2) )
772  {
773  for ( i = 0; i < n2->num_nodes; i++ )
774  {
775  d = circ_tree_distance_tree_internal(n1, n2->nodes[i], threshold, min_dist, max_dist, closest1, closest2);
776  d_min = FP_MIN(d_min, d);
777  }
778  }
779  else
780  {
781  /* Never get here */
782  }
783 
784  return d_min;
785  }
786 }
double sphere_distance(const GEOGRAPHIC_POINT *s, const GEOGRAPHIC_POINT *e)
Given two points on a unit sphere, calculate their distance apart in radians.
Definition: lwgeodetic.c:913
double edge_distance_to_edge(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *closest1, GEOGRAPHIC_POINT *closest2)
Calculate the distance between two edges.
Definition: lwgeodetic.c:1234
Two-point great circle segment from a to b.
Definition: lwgeodetic.h:56
uint32_t num_nodes
uint32_t geom_type
int circ_tree_get_point(const CIRC_NODE *node, POINT2D *pt)
Returns a POINT2D that is a vertex of the input shape.
POINT2D * p2
#define POLYGONTYPE
Definition: liblwgeom.h:86
POINT2D * p1
#define LWDEBUG(level, msg)
Definition: lwgeom_log.h:83
static double circ_tree_distance_tree_internal(const CIRC_NODE *n1, const CIRC_NODE *n2, double threshold, double *min_dist, double *max_dist, GEOGRAPHIC_POINT *closest1, GEOGRAPHIC_POINT *closest2)
#define FP_MIN(A, B)
Point in spherical coordinates on the world.
Definition: lwgeodetic.h:47
unsigned int uint32_t
Definition: uthash.h:78
double x
Definition: liblwgeom.h:327
static int circ_node_is_leaf(const CIRC_NODE *node)
Internal nodes have their point references set to NULL.
static double circ_node_max_distance(const CIRC_NODE *n1, const CIRC_NODE *n2)
GEOGRAPHIC_POINT start
Definition: lwgeodetic.h:58
double edge_distance_to_point(const GEOGRAPHIC_EDGE *e, const GEOGRAPHIC_POINT *gp, GEOGRAPHIC_POINT *closest)
Definition: lwgeodetic.c:1183
int circ_tree_contains_point(const CIRC_NODE *node, const POINT2D *pt, const POINT2D *pt_outside, int *on_boundary)
Walk the tree and count intersections between the stab line and the edges.
int lwtype_is_collection(uint8_t type)
Determine whether a type number is a collection or not.
Definition: lwgeom.c:1086
uint32_t edge_intersects(const POINT3D *A1, const POINT3D *A2, const POINT3D *B1, const POINT3D *B2)
Returns non-zero if edges A and B interact.
Definition: lwgeodetic.c:3411
GEOGRAPHIC_POINT end
Definition: lwgeodetic.h:59
double y
Definition: liblwgeom.h:327
void geog2cart(const GEOGRAPHIC_POINT *g, POINT3D *p)
Convert spherical coordinates to cartesion coordinates on unit sphere.
Definition: lwgeodetic.c:369
static double circ_node_min_distance(const CIRC_NODE *n1, const CIRC_NODE *n2)
void geographic_point_init(double lon, double lat, GEOGRAPHIC_POINT *g)
Initialize a geographic point.
Definition: lwgeodetic.c:171
POINT2D pt_outside
#define LWDEBUGF(level, msg,...)
Definition: lwgeom_log.h:88
int edge_intersection(const GEOGRAPHIC_EDGE *e1, const GEOGRAPHIC_EDGE *e2, GEOGRAPHIC_POINT *g)
Returns true if an intersection can be calculated, and places it in *g.
Definition: lwgeodetic.c:1092
struct circ_node ** nodes

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