TLA  Line data    Source code

       1                 : /*-------------------------------------------------------------------------
       2                 :  *
       3                 :  * spgproc.c
       4                 :  *    Common supporting procedures for SP-GiST opclasses.
       5                 :  *
       6                 :  *
       7                 :  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
       8                 :  * Portions Copyright (c) 1994, Regents of the University of California
       9                 :  *
      10                 :  * IDENTIFICATION
      11                 :  *          src/backend/access/spgist/spgproc.c
      12                 :  *
      13                 :  *-------------------------------------------------------------------------
      14                 :  */
      15                 : 
      16                 : #include "postgres.h"
      17                 : 
      18                 : #include <math.h>
      19                 : 
      20                 : #include "access/spgist_private.h"
      21                 : #include "utils/builtins.h"
      22                 : #include "utils/float.h"
      23                 : #include "utils/geo_decls.h"
      24                 : 
      25                 : #define point_point_distance(p1,p2) \
      26                 :     DatumGetFloat8(DirectFunctionCall2(point_distance, \
      27                 :                                        PointPGetDatum(p1), PointPGetDatum(p2)))
      28                 : 
      29                 : /* Point-box distance in the assumption that box is aligned by axis */
      30                 : static double
      31 CBC       47052 : point_box_distance(Point *point, BOX *box)
      32                 : {
      33                 :     double      dx,
      34                 :                 dy;
      35                 : 
      36           47052 :     if (isnan(point->x) || isnan(box->low.x) ||
      37           47052 :         isnan(point->y) || isnan(box->low.y))
      38 UBC           0 :         return get_float8_nan();
      39                 : 
      40 CBC       47052 :     if (point->x < box->low.x)
      41           42834 :         dx = box->low.x - point->x;
      42            4218 :     else if (point->x > box->high.x)
      43            3330 :         dx = point->x - box->high.x;
      44                 :     else
      45             888 :         dx = 0.0;
      46                 : 
      47           47052 :     if (point->y < box->low.y)
      48           22632 :         dy = box->low.y - point->y;
      49           24420 :     else if (point->y > box->high.y)
      50           23862 :         dy = point->y - box->high.y;
      51                 :     else
      52             558 :         dy = 0.0;
      53                 : 
      54           47052 :     return HYPOT(dx, dy);
      55                 : }
      56                 : 
      57                 : /*
      58                 :  * Returns distances from given key to array of ordering scan keys.  Leaf key
      59                 :  * is expected to be point, non-leaf key is expected to be box.  Scan key
      60                 :  * arguments are expected to be points.
      61                 :  */
      62                 : double *
      63          186636 : spg_key_orderbys_distances(Datum key, bool isLeaf,
      64                 :                            ScanKey orderbys, int norderbys)
      65                 : {
      66                 :     int         sk_num;
      67          186636 :     double     *distances = (double *) palloc(norderbys * sizeof(double)),
      68          186636 :                *distance = distances;
      69                 : 
      70          374226 :     for (sk_num = 0; sk_num < norderbys; ++sk_num, ++orderbys, ++distance)
      71                 :     {
      72          187590 :         Point      *point = DatumGetPointP(orderbys->sk_argument);
      73                 : 
      74          187590 :         *distance = isLeaf ? point_point_distance(point, DatumGetPointP(key))
      75          187590 :             : point_box_distance(point, DatumGetBoxP(key));
      76                 :     }
      77                 : 
      78          186636 :     return distances;
      79                 : }
      80                 : 
      81                 : BOX *
      82            2001 : box_copy(BOX *orig)
      83                 : {
      84            2001 :     BOX        *result = palloc(sizeof(BOX));
      85                 : 
      86            2001 :     *result = *orig;
      87            2001 :     return result;
      88                 : }