pgLatLon

annotate latlon-v0003.c @ 9:dc8da756b761

Changed version to 0.3
author jbe
date Fri Sep 02 14:04:04 2016 +0200 (2016-09-02)
parents latlon-v0002.c@bccc1e155ad8
children 684a78d2f9f0
rev   line source
jbe@0 1
jbe@0 2 /*-------------*
jbe@0 3 * C prelude *
jbe@0 4 *-------------*/
jbe@0 5
jbe@0 6 #include "postgres.h"
jbe@0 7 #include "fmgr.h"
jbe@0 8 #include "libpq/pqformat.h"
jbe@0 9 #include "access/gist.h"
jbe@0 10 #include "access/stratnum.h"
jbe@0 11 #include "utils/array.h"
jbe@0 12 #include <math.h>
jbe@0 13
jbe@0 14 #ifdef PG_MODULE_MAGIC
jbe@0 15 PG_MODULE_MAGIC;
jbe@0 16 #endif
jbe@0 17
jbe@0 18 #if INT_MAX < 2147483647
jbe@0 19 #error Expected int type to be at least 32 bit wide
jbe@0 20 #endif
jbe@0 21
jbe@0 22
jbe@0 23 /*---------------------------------*
jbe@0 24 * distance calculation on earth *
jbe@0 25 * (using WGS-84 spheroid) *
jbe@0 26 *---------------------------------*/
jbe@0 27
jbe@0 28 /* WGS-84 spheroid with following parameters:
jbe@0 29 semi-major axis a = 6378137
jbe@0 30 semi-minor axis b = a * (1 - 1/298.257223563)
jbe@0 31 estimated diameter = 2 * (2*a+b)/3
jbe@0 32 */
jbe@0 33 #define PGL_SPHEROID_A 6378137.0 /* semi major axis */
jbe@0 34 #define PGL_SPHEROID_F (1.0/298.257223563) /* flattening */
jbe@0 35 #define PGL_SPHEROID_B (PGL_SPHEROID_A * (1.0-PGL_SPHEROID_F))
jbe@0 36 #define PGL_EPS2 ( ( PGL_SPHEROID_A * PGL_SPHEROID_A - \
jbe@0 37 PGL_SPHEROID_B * PGL_SPHEROID_B ) / \
jbe@0 38 ( PGL_SPHEROID_A * PGL_SPHEROID_A ) )
jbe@0 39 #define PGL_SUBEPS2 (1.0-PGL_EPS2)
jbe@0 40 #define PGL_DIAMETER ((4.0*PGL_SPHEROID_A + 2.0*PGL_SPHEROID_B) / 3.0)
jbe@0 41 #define PGL_SCALE (PGL_SPHEROID_A / PGL_DIAMETER) /* semi-major ref. */
jbe@0 42 #define PGL_FADELIMIT (PGL_DIAMETER * M_PI / 6.0) /* 1/6 circumference */
jbe@0 43 #define PGL_MAXDIST (PGL_DIAMETER * M_PI / 2.0) /* maximum distance */
jbe@0 44
jbe@0 45 /* calculate distance between two points on earth (given in degrees) */
jbe@0 46 static inline double pgl_distance(
jbe@0 47 double lat1, double lon1, double lat2, double lon2
jbe@0 48 ) {
jbe@0 49 float8 lat1cos, lat1sin, lat2cos, lat2sin, lon2cos, lon2sin;
jbe@0 50 float8 nphi1, nphi2, x1, z1, x2, y2, z2, g, s, t;
jbe@0 51 /* normalize delta longitude (lon2 > 0 && lon1 = 0) */
jbe@0 52 /* lon1 = 0 (not used anymore) */
jbe@0 53 lon2 = fabs(lon2-lon1);
jbe@0 54 /* convert to radians (first divide, then multiply) */
jbe@0 55 lat1 = (lat1 / 180.0) * M_PI;
jbe@0 56 lat2 = (lat2 / 180.0) * M_PI;
jbe@0 57 lon2 = (lon2 / 180.0) * M_PI;
jbe@0 58 /* make lat2 >= lat1 to ensure reversal-symmetry despite floating point
jbe@0 59 operations (lon2 >= lon1 is already ensured in a previous step) */
jbe@0 60 if (lat2 < lat1) { float8 swap = lat1; lat1 = lat2; lat2 = swap; }
jbe@0 61 /* calculate 3d coordinates on scaled ellipsoid which has an average diameter
jbe@0 62 of 1.0 */
jbe@0 63 lat1cos = cos(lat1); lat1sin = sin(lat1);
jbe@0 64 lat2cos = cos(lat2); lat2sin = sin(lat2);
jbe@0 65 lon2cos = cos(lon2); lon2sin = sin(lon2);
jbe@0 66 nphi1 = PGL_SCALE / sqrt(1 - PGL_EPS2 * lat1sin * lat1sin);
jbe@0 67 nphi2 = PGL_SCALE / sqrt(1 - PGL_EPS2 * lat2sin * lat2sin);
jbe@0 68 x1 = nphi1 * lat1cos;
jbe@0 69 z1 = nphi1 * PGL_SUBEPS2 * lat1sin;
jbe@0 70 x2 = nphi2 * lat2cos * lon2cos;
jbe@0 71 y2 = nphi2 * lat2cos * lon2sin;
jbe@0 72 z2 = nphi2 * PGL_SUBEPS2 * lat2sin;
jbe@0 73 /* calculate tunnel distance through scaled (diameter 1.0) ellipsoid */
jbe@0 74 g = sqrt((x2-x1)*(x2-x1) + y2*y2 + (z2-z1)*(z2-z1));
jbe@0 75 /* convert tunnel distance through scaled ellipsoid to approximated surface
jbe@0 76 distance on original ellipsoid */
jbe@0 77 if (g > 1.0) g = 1.0;
jbe@0 78 s = PGL_DIAMETER * asin(g);
jbe@0 79 /* return result only if small enough to be precise (less than 1/3 of
jbe@0 80 maximum possible distance) */
jbe@0 81 if (s <= PGL_FADELIMIT) return s;
jbe@0 82 /* calculate tunnel distance to antipodal point through scaled ellipsoid */
jbe@3 83 g = sqrt((x2+x1)*(x2+x1) + y2*y2 + (z2+z1)*(z2+z1));
jbe@0 84 /* convert tunnel distance to antipodal point through scaled ellipsoid to
jbe@0 85 approximated surface distance to antipodal point on original ellipsoid */
jbe@0 86 if (g > 1.0) g = 1.0;
jbe@0 87 t = PGL_DIAMETER * asin(g);
jbe@0 88 /* surface distance between original points can now be approximated by
jbe@0 89 substracting antipodal distance from maximum possible distance;
jbe@0 90 return result only if small enough (less than 1/3 of maximum possible
jbe@0 91 distance) */
jbe@0 92 if (t <= PGL_FADELIMIT) return PGL_MAXDIST-t;
jbe@0 93 /* otherwise crossfade direct and antipodal result to ensure monotonicity */
jbe@0 94 return (
jbe@0 95 (s * (t-PGL_FADELIMIT) + (PGL_MAXDIST-t) * (s-PGL_FADELIMIT)) /
jbe@0 96 (s + t - 2*PGL_FADELIMIT)
jbe@0 97 );
jbe@0 98 }
jbe@0 99
jbe@0 100 /* finite distance that can not be reached on earth */
jbe@0 101 #define PGL_ULTRA_DISTANCE (3 * PGL_MAXDIST)
jbe@0 102
jbe@0 103
jbe@0 104 /*--------------------------------*
jbe@0 105 * simple geographic data types *
jbe@0 106 *--------------------------------*/
jbe@0 107
jbe@0 108 /* point on earth given by latitude and longitude in degrees */
jbe@0 109 /* (type "epoint" in SQL) */
jbe@0 110 typedef struct {
jbe@0 111 double lat; /* between -90 and 90 (both inclusive) */
jbe@0 112 double lon; /* between -180 and 180 (both inclusive) */
jbe@0 113 } pgl_point;
jbe@0 114
jbe@0 115 /* box delimited by two parallels and two meridians (all in degrees) */
jbe@0 116 /* (type "ebox" in SQL) */
jbe@0 117 typedef struct {
jbe@0 118 double lat_min; /* between -90 and 90 (both inclusive) */
jbe@0 119 double lat_max; /* between -90 and 90 (both inclusive) */
jbe@0 120 double lon_min; /* between -180 and 180 (both inclusive) */
jbe@0 121 double lon_max; /* between -180 and 180 (both inclusive) */
jbe@0 122 /* if lat_min > lat_max, then box is empty */
jbe@0 123 /* if lon_min > lon_max, then 180th meridian is crossed */
jbe@0 124 } pgl_box;
jbe@0 125
jbe@0 126 /* circle on earth surface (for radial searches with fixed radius) */
jbe@0 127 /* (type "ecircle" in SQL) */
jbe@0 128 typedef struct {
jbe@0 129 pgl_point center;
jbe@0 130 double radius; /* positive (including +0 but excluding -0), or -INFINITY */
jbe@0 131 /* A negative radius (i.e. -INFINITY) denotes nothing (i.e. no point),
jbe@0 132 zero radius (0) denotes a single point,
jbe@0 133 a finite radius (0 < radius < INFINITY) denotes a filled circle, and
jbe@0 134 a radius of INFINITY is valid and means complete coverage of earth. */
jbe@0 135 } pgl_circle;
jbe@0 136
jbe@0 137
jbe@0 138 /*----------------------------------*
jbe@0 139 * geographic "cluster" data type *
jbe@0 140 *----------------------------------*/
jbe@0 141
jbe@0 142 /* A cluster is a collection of points, paths, outlines, and polygons. If two
jbe@0 143 polygons in a cluster overlap, the area covered by both polygons does not
jbe@0 144 belong to the cluster. This way, a cluster can be used to describe complex
jbe@0 145 shapes like polygons with holes. Outlines are non-filled polygons. Paths are
jbe@0 146 open by default (i.e. the last point in the list is not connected with the
jbe@0 147 first point in the list). Note that each outline or polygon in a cluster
jbe@0 148 must cover a longitude range of less than 180 degrees to avoid ambiguities.
jbe@0 149 Areas which are larger may be split into multiple polygons. */
jbe@0 150
jbe@0 151 /* maximum number of points in a cluster */
jbe@0 152 /* (limited to avoid integer overflows, e.g. when allocating memory) */
jbe@0 153 #define PGL_CLUSTER_MAXPOINTS 16777216
jbe@0 154
jbe@0 155 /* types of cluster entries */
jbe@0 156 #define PGL_ENTRY_POINT 1 /* a point */
jbe@0 157 #define PGL_ENTRY_PATH 2 /* a path from first point to last point */
jbe@0 158 #define PGL_ENTRY_OUTLINE 3 /* a non-filled polygon with given vertices */
jbe@0 159 #define PGL_ENTRY_POLYGON 4 /* a filled polygon with given vertices */
jbe@0 160
jbe@0 161 /* Entries of a cluster are described by two different structs: pgl_newentry
jbe@0 162 and pgl_entry. The first is used only during construction of a cluster, the
jbe@0 163 second is used in all other cases (e.g. when reading clusters from the
jbe@0 164 database, performing operations, etc). */
jbe@0 165
jbe@0 166 /* entry for new geographic cluster during construction of that cluster */
jbe@0 167 typedef struct {
jbe@0 168 int32_t entrytype;
jbe@0 169 int32_t npoints;
jbe@0 170 pgl_point *points; /* pointer to an array of points (pgl_point) */
jbe@0 171 } pgl_newentry;
jbe@0 172
jbe@0 173 /* entry of geographic cluster */
jbe@0 174 typedef struct {
jbe@0 175 int32_t entrytype; /* type of entry: point, path, outline, polygon */
jbe@0 176 int32_t npoints; /* number of stored points (set to 1 for point entry) */
jbe@0 177 int32_t offset; /* offset of pgl_point array from cluster base address */
jbe@0 178 /* use macro PGL_ENTRY_POINTS to obtain a pointer to the array of points */
jbe@0 179 } pgl_entry;
jbe@0 180
jbe@0 181 /* geographic cluster which is a collection of points, (open) paths, polygons,
jbe@0 182 and outlines (non-filled polygons) */
jbe@0 183 typedef struct {
jbe@0 184 char header[VARHDRSZ]; /* PostgreSQL header for variable size data types */
jbe@0 185 int32_t nentries; /* number of stored points */
jbe@0 186 pgl_circle bounding; /* bounding circle */
jbe@0 187 /* Note: bounding circle ensures alignment of pgl_cluster for points */
jbe@0 188 pgl_entry entries[FLEXIBLE_ARRAY_MEMBER]; /* var-length data */
jbe@0 189 } pgl_cluster;
jbe@0 190
jbe@0 191 /* macro to determine memory alignment of points */
jbe@0 192 /* (needed to store pgl_point array after entries in pgl_cluster) */
jbe@0 193 typedef struct { char dummy; pgl_point aligned; } pgl_point_alignment;
jbe@0 194 #define PGL_POINT_ALIGNMENT offsetof(pgl_point_alignment, aligned)
jbe@0 195
jbe@0 196 /* macro to extract a pointer to the array of points of a cluster entry */
jbe@0 197 #define PGL_ENTRY_POINTS(cluster, idx) \
jbe@0 198 ((pgl_point *)(((intptr_t)cluster)+(cluster)->entries[idx].offset))
jbe@0 199
jbe@0 200 /* convert pgl_newentry array to pgl_cluster */
jbe@0 201 static pgl_cluster *pgl_new_cluster(int nentries, pgl_newentry *entries) {
jbe@0 202 int i; /* index of current entry */
jbe@0 203 int npoints = 0; /* number of points in whole cluster */
jbe@0 204 int entry_npoints; /* number of points in current entry */
jbe@0 205 int points_offset = PGL_POINT_ALIGNMENT * (
jbe@0 206 ( offsetof(pgl_cluster, entries) +
jbe@0 207 nentries * sizeof(pgl_entry) +
jbe@0 208 PGL_POINT_ALIGNMENT - 1
jbe@0 209 ) / PGL_POINT_ALIGNMENT
jbe@0 210 ); /* offset of pgl_point array from base address (considering alignment) */
jbe@0 211 pgl_cluster *cluster; /* new cluster to be returned */
jbe@0 212 /* determine total number of points */
jbe@0 213 for (i=0; i<nentries; i++) npoints += entries[i].npoints;
jbe@0 214 /* allocate memory for cluster (including entries and points) */
jbe@0 215 cluster = palloc(points_offset + npoints * sizeof(pgl_point));
jbe@0 216 /* re-count total number of points to determine offset for each entry */
jbe@0 217 npoints = 0;
jbe@0 218 /* copy entries and points */
jbe@0 219 for (i=0; i<nentries; i++) {
jbe@0 220 /* determine number of points in entry */
jbe@0 221 entry_npoints = entries[i].npoints;
jbe@0 222 /* copy entry */
jbe@0 223 cluster->entries[i].entrytype = entries[i].entrytype;
jbe@0 224 cluster->entries[i].npoints = entry_npoints;
jbe@0 225 /* calculate offset (in bytes) of pgl_point array */
jbe@0 226 cluster->entries[i].offset = points_offset + npoints * sizeof(pgl_point);
jbe@0 227 /* copy points */
jbe@0 228 memcpy(
jbe@0 229 PGL_ENTRY_POINTS(cluster, i),
jbe@0 230 entries[i].points,
jbe@0 231 entry_npoints * sizeof(pgl_point)
jbe@0 232 );
jbe@0 233 /* update total number of points processed */
jbe@0 234 npoints += entry_npoints;
jbe@0 235 }
jbe@0 236 /* set number of entries in cluster */
jbe@0 237 cluster->nentries = nentries;
jbe@0 238 /* set PostgreSQL header for variable sized data */
jbe@0 239 SET_VARSIZE(cluster, points_offset + npoints * sizeof(pgl_point));
jbe@0 240 /* return newly created cluster */
jbe@0 241 return cluster;
jbe@0 242 }
jbe@0 243
jbe@0 244
jbe@0 245 /*----------------------------------------*
jbe@0 246 * C functions on geographic data types *
jbe@0 247 *----------------------------------------*/
jbe@0 248
jbe@0 249 /* round latitude or longitude to 12 digits after decimal point */
jbe@0 250 static inline double pgl_round(double val) {
jbe@0 251 return round(val * 1e12) / 1e12;
jbe@0 252 }
jbe@0 253
jbe@0 254 /* compare two points */
jbe@0 255 /* (equality when same point on earth is described, otherwise an arbitrary
jbe@0 256 linear order) */
jbe@0 257 static int pgl_point_cmp(pgl_point *point1, pgl_point *point2) {
jbe@0 258 double lon1, lon2; /* modified longitudes for special cases */
jbe@0 259 /* use latitude as first ordering criterion */
jbe@0 260 if (point1->lat < point2->lat) return -1;
jbe@0 261 if (point1->lat > point2->lat) return 1;
jbe@0 262 /* determine modified longitudes (considering special case of poles and
jbe@0 263 180th meridian which can be described as W180 or E180) */
jbe@0 264 if (point1->lat == -90 || point1->lat == 90) lon1 = 0;
jbe@0 265 else if (point1->lon == 180) lon1 = -180;
jbe@0 266 else lon1 = point1->lon;
jbe@0 267 if (point2->lat == -90 || point2->lat == 90) lon2 = 0;
jbe@0 268 else if (point2->lon == 180) lon2 = -180;
jbe@0 269 else lon2 = point2->lon;
jbe@0 270 /* use (modified) longitude as secondary ordering criterion */
jbe@0 271 if (lon1 < lon2) return -1;
jbe@0 272 if (lon1 > lon2) return 1;
jbe@0 273 /* no difference found, points are equal */
jbe@0 274 return 0;
jbe@0 275 }
jbe@0 276
jbe@0 277 /* compare two boxes */
jbe@0 278 /* (equality when same box on earth is described, otherwise an arbitrary linear
jbe@0 279 order) */
jbe@0 280 static int pgl_box_cmp(pgl_box *box1, pgl_box *box2) {
jbe@0 281 /* two empty boxes are equal, and an empty box is always considered "less
jbe@0 282 than" a non-empty box */
jbe@0 283 if (box1->lat_min> box1->lat_max && box2->lat_min<=box2->lat_max) return -1;
jbe@0 284 if (box1->lat_min> box1->lat_max && box2->lat_min> box2->lat_max) return 0;
jbe@0 285 if (box1->lat_min<=box1->lat_max && box2->lat_min> box2->lat_max) return 1;
jbe@0 286 /* use southern border as first ordering criterion */
jbe@0 287 if (box1->lat_min < box2->lat_min) return -1;
jbe@0 288 if (box1->lat_min > box2->lat_min) return 1;
jbe@0 289 /* use northern border as second ordering criterion */
jbe@0 290 if (box1->lat_max < box2->lat_max) return -1;
jbe@0 291 if (box1->lat_max > box2->lat_max) return 1;
jbe@0 292 /* use western border as third ordering criterion */
jbe@0 293 if (box1->lon_min < box2->lon_min) return -1;
jbe@0 294 if (box1->lon_min > box2->lon_min) return 1;
jbe@0 295 /* use eastern border as fourth ordering criterion */
jbe@0 296 if (box1->lon_max < box2->lon_max) return -1;
jbe@0 297 if (box1->lon_max > box2->lon_max) return 1;
jbe@0 298 /* no difference found, boxes are equal */
jbe@0 299 return 0;
jbe@0 300 }
jbe@0 301
jbe@0 302 /* compare two circles */
jbe@0 303 /* (equality when same circle on earth is described, otherwise an arbitrary
jbe@0 304 linear order) */
jbe@0 305 static int pgl_circle_cmp(pgl_circle *circle1, pgl_circle *circle2) {
jbe@0 306 /* two circles with same infinite radius (positive or negative infinity) are
jbe@0 307 considered equal independently of center point */
jbe@0 308 if (
jbe@0 309 !isfinite(circle1->radius) && !isfinite(circle2->radius) &&
jbe@0 310 circle1->radius == circle2->radius
jbe@0 311 ) return 0;
jbe@0 312 /* use radius as first ordering criterion */
jbe@0 313 if (circle1->radius < circle2->radius) return -1;
jbe@0 314 if (circle1->radius > circle2->radius) return 1;
jbe@0 315 /* use center point as secondary ordering criterion */
jbe@0 316 return pgl_point_cmp(&(circle1->center), &(circle2->center));
jbe@0 317 }
jbe@0 318
jbe@0 319 /* set box to empty box*/
jbe@0 320 static void pgl_box_set_empty(pgl_box *box) {
jbe@0 321 box->lat_min = INFINITY;
jbe@0 322 box->lat_max = -INFINITY;
jbe@0 323 box->lon_min = 0;
jbe@0 324 box->lon_max = 0;
jbe@0 325 }
jbe@0 326
jbe@0 327 /* check if point is inside a box */
jbe@0 328 static bool pgl_point_in_box(pgl_point *point, pgl_box *box) {
jbe@0 329 return (
jbe@0 330 point->lat >= box->lat_min && point->lat <= box->lat_max && (
jbe@0 331 (box->lon_min > box->lon_max) ? (
jbe@0 332 /* box crosses 180th meridian */
jbe@0 333 point->lon >= box->lon_min || point->lon <= box->lon_max
jbe@0 334 ) : (
jbe@0 335 /* box does not cross the 180th meridian */
jbe@0 336 point->lon >= box->lon_min && point->lon <= box->lon_max
jbe@0 337 )
jbe@0 338 )
jbe@0 339 );
jbe@0 340 }
jbe@0 341
jbe@0 342 /* check if two boxes overlap */
jbe@0 343 static bool pgl_boxes_overlap(pgl_box *box1, pgl_box *box2) {
jbe@0 344 return (
jbe@0 345 box2->lat_max >= box2->lat_min && /* ensure box2 is not empty */
jbe@0 346 ( box2->lat_min >= box1->lat_min || box2->lat_max >= box1->lat_min ) &&
jbe@0 347 ( box2->lat_min <= box1->lat_max || box2->lat_max <= box1->lat_max ) && (
jbe@0 348 (
jbe@0 349 /* check if one and only one box crosses the 180th meridian */
jbe@0 350 ((box1->lon_min > box1->lon_max) ? 1 : 0) ^
jbe@0 351 ((box2->lon_min > box2->lon_max) ? 1 : 0)
jbe@0 352 ) ? (
jbe@0 353 /* exactly one box crosses the 180th meridian */
jbe@0 354 box2->lon_min >= box1->lon_min || box2->lon_max >= box1->lon_min ||
jbe@0 355 box2->lon_min <= box1->lon_max || box2->lon_max <= box1->lon_max
jbe@0 356 ) : (
jbe@0 357 /* no box or both boxes cross the 180th meridian */
jbe@0 358 (
jbe@0 359 (box2->lon_min >= box1->lon_min || box2->lon_max >= box1->lon_min) &&
jbe@0 360 (box2->lon_min <= box1->lon_max || box2->lon_max <= box1->lon_max)
jbe@0 361 ) ||
jbe@0 362 /* handle W180 == E180 */
jbe@0 363 ( box1->lon_min == -180 && box2->lon_max == 180 ) ||
jbe@0 364 ( box2->lon_min == -180 && box1->lon_max == 180 )
jbe@0 365 )
jbe@0 366 )
jbe@0 367 );
jbe@0 368 }
jbe@0 369
jbe@0 370 /* check unambiguousness of east/west orientation of cluster entries and set
jbe@0 371 bounding circle of cluster */
jbe@0 372 static bool pgl_finalize_cluster(pgl_cluster *cluster) {
jbe@0 373 int i, j; /* i: index of entry, j: index of point in entry */
jbe@0 374 int npoints; /* number of points in entry */
jbe@0 375 int total_npoints = 0; /* total number of points in cluster */
jbe@0 376 pgl_point *points; /* points in entry */
jbe@0 377 int lon_dir; /* first point of entry west (-1) or east (+1) */
jbe@0 378 double lon_break = 0; /* antipodal longitude of first point in entry */
jbe@0 379 double lon_min, lon_max; /* covered longitude range of entry */
jbe@0 380 double value; /* temporary variable */
jbe@0 381 /* reset bounding circle center to empty circle at 0/0 coordinates */
jbe@0 382 cluster->bounding.center.lat = 0;
jbe@0 383 cluster->bounding.center.lon = 0;
jbe@0 384 cluster->bounding.radius = -INFINITY;
jbe@0 385 /* if cluster is not empty */
jbe@0 386 if (cluster->nentries != 0) {
jbe@0 387 /* iterate over all cluster entries and ensure they each cover a longitude
jbe@0 388 range less than 180 degrees */
jbe@0 389 for (i=0; i<cluster->nentries; i++) {
jbe@0 390 /* get properties of entry */
jbe@0 391 npoints = cluster->entries[i].npoints;
jbe@0 392 points = PGL_ENTRY_POINTS(cluster, i);
jbe@0 393 /* get longitude of first point of entry */
jbe@0 394 value = points[0].lon;
jbe@0 395 /* initialize lon_min and lon_max with longitude of first point */
jbe@0 396 lon_min = value;
jbe@0 397 lon_max = value;
jbe@0 398 /* determine east/west orientation of first point and calculate antipodal
jbe@0 399 longitude (Note: rounding required here) */
jbe@0 400 if (value < 0) { lon_dir = -1; lon_break = pgl_round(value + 180); }
jbe@0 401 else if (value > 0) { lon_dir = 1; lon_break = pgl_round(value - 180); }
jbe@0 402 else lon_dir = 0;
jbe@0 403 /* iterate over all other points in entry */
jbe@0 404 for (j=1; j<npoints; j++) {
jbe@0 405 /* consider longitude wrap-around */
jbe@0 406 value = points[j].lon;
jbe@0 407 if (lon_dir<0 && value>lon_break) value = pgl_round(value - 360);
jbe@0 408 else if (lon_dir>0 && value<lon_break) value = pgl_round(value + 360);
jbe@0 409 /* update lon_min and lon_max */
jbe@0 410 if (value < lon_min) lon_min = value;
jbe@0 411 else if (value > lon_max) lon_max = value;
jbe@0 412 /* return false if 180 degrees or more are covered */
jbe@0 413 if (lon_max - lon_min >= 180) return false;
jbe@0 414 }
jbe@0 415 }
jbe@0 416 /* iterate over all points of all entries and calculate arbitrary center
jbe@0 417 point for bounding circle (best if center point minimizes the radius,
jbe@0 418 but some error is allowed here) */
jbe@0 419 for (i=0; i<cluster->nentries; i++) {
jbe@0 420 /* get properties of entry */
jbe@0 421 npoints = cluster->entries[i].npoints;
jbe@0 422 points = PGL_ENTRY_POINTS(cluster, i);
jbe@0 423 /* check if first entry */
jbe@0 424 if (i==0) {
jbe@0 425 /* get longitude of first point of first entry in whole cluster */
jbe@0 426 value = points[0].lon;
jbe@0 427 /* initialize lon_min and lon_max with longitude of first point of
jbe@0 428 first entry in whole cluster (used to determine if whole cluster
jbe@0 429 covers a longitude range of 180 degrees or more) */
jbe@0 430 lon_min = value;
jbe@0 431 lon_max = value;
jbe@0 432 /* determine east/west orientation of first point and calculate
jbe@0 433 antipodal longitude (Note: rounding not necessary here) */
jbe@0 434 if (value < 0) { lon_dir = -1; lon_break = value + 180; }
jbe@0 435 else if (value > 0) { lon_dir = 1; lon_break = value - 180; }
jbe@0 436 else lon_dir = 0;
jbe@0 437 }
jbe@0 438 /* iterate over all points in entry */
jbe@0 439 for (j=0; j<npoints; j++) {
jbe@0 440 /* longitude wrap-around (Note: rounding not necessary here) */
jbe@0 441 value = points[j].lon;
jbe@0 442 if (lon_dir < 0 && value > lon_break) value -= 360;
jbe@0 443 else if (lon_dir > 0 && value < lon_break) value += 360;
jbe@0 444 if (value < lon_min) lon_min = value;
jbe@0 445 else if (value > lon_max) lon_max = value;
jbe@0 446 /* set bounding circle to cover whole earth if more than 180 degrees
jbe@0 447 are covered */
jbe@0 448 if (lon_max - lon_min >= 180) {
jbe@0 449 cluster->bounding.center.lat = 0;
jbe@0 450 cluster->bounding.center.lon = 0;
jbe@0 451 cluster->bounding.radius = INFINITY;
jbe@0 452 return true;
jbe@0 453 }
jbe@0 454 /* add point to bounding circle center (for average calculation) */
jbe@0 455 cluster->bounding.center.lat += points[j].lat;
jbe@0 456 cluster->bounding.center.lon += value;
jbe@0 457 }
jbe@0 458 /* count total number of points */
jbe@0 459 total_npoints += npoints;
jbe@0 460 }
jbe@0 461 /* determine average latitude and longitude of cluster */
jbe@0 462 cluster->bounding.center.lat /= total_npoints;
jbe@0 463 cluster->bounding.center.lon /= total_npoints;
jbe@0 464 /* normalize longitude of center of cluster bounding circle */
jbe@0 465 if (cluster->bounding.center.lon < -180) {
jbe@0 466 cluster->bounding.center.lon += 360;
jbe@0 467 }
jbe@0 468 else if (cluster->bounding.center.lon > 180) {
jbe@0 469 cluster->bounding.center.lon -= 360;
jbe@0 470 }
jbe@0 471 /* round bounding circle center (useful if it is used by other functions) */
jbe@0 472 cluster->bounding.center.lat = pgl_round(cluster->bounding.center.lat);
jbe@0 473 cluster->bounding.center.lon = pgl_round(cluster->bounding.center.lon);
jbe@0 474 /* calculate radius of bounding circle */
jbe@0 475 for (i=0; i<cluster->nentries; i++) {
jbe@0 476 npoints = cluster->entries[i].npoints;
jbe@0 477 points = PGL_ENTRY_POINTS(cluster, i);
jbe@0 478 for (j=0; j<npoints; j++) {
jbe@0 479 value = pgl_distance(
jbe@0 480 cluster->bounding.center.lat, cluster->bounding.center.lon,
jbe@0 481 points[j].lat, points[j].lon
jbe@0 482 );
jbe@0 483 if (value > cluster->bounding.radius) cluster->bounding.radius = value;
jbe@0 484 }
jbe@0 485 }
jbe@0 486 }
jbe@0 487 /* return true (east/west orientation is unambiguous) */
jbe@0 488 return true;
jbe@0 489 }
jbe@0 490
jbe@0 491 /* check if point is inside cluster */
jbe@0 492 static bool pgl_point_in_cluster(pgl_point *point, pgl_cluster *cluster) {
jbe@0 493 int i, j, k; /* i: entry, j: point in entry, k: next point in entry */
jbe@0 494 int entrytype; /* type of entry */
jbe@0 495 int npoints; /* number of points in entry */
jbe@0 496 pgl_point *points; /* array of points in entry */
jbe@0 497 int lon_dir = 0; /* first vertex west (-1) or east (+1) */
jbe@0 498 double lon_break = 0; /* antipodal longitude of first vertex */
jbe@0 499 double lat0 = point->lat; /* latitude of point */
jbe@0 500 double lon0; /* (adjusted) longitude of point */
jbe@0 501 double lat1, lon1; /* latitude and (adjusted) longitude of vertex */
jbe@0 502 double lat2, lon2; /* latitude and (adjusted) longitude of next vertex */
jbe@0 503 double lon; /* longitude of intersection */
jbe@0 504 int counter = 0; /* counter for intersections east of point */
jbe@0 505 /* points outside bounding circle are always assumed to be non-overlapping */
jbe@0 506 /* (necessary for consistent table and index scans) */
jbe@0 507 if (
jbe@0 508 pgl_distance(
jbe@0 509 point->lat, point->lon,
jbe@0 510 cluster->bounding.center.lat, cluster->bounding.center.lon
jbe@0 511 ) > cluster->bounding.radius
jbe@0 512 ) return false;
jbe@0 513 /* iterate over all entries */
jbe@0 514 for (i=0; i<cluster->nentries; i++) {
jbe@0 515 /* get properties of entry */
jbe@0 516 entrytype = cluster->entries[i].entrytype;
jbe@0 517 npoints = cluster->entries[i].npoints;
jbe@0 518 points = PGL_ENTRY_POINTS(cluster, i);
jbe@0 519 /* determine east/west orientation of first point of entry and calculate
jbe@0 520 antipodal longitude */
jbe@0 521 lon_break = points[0].lon;
jbe@0 522 if (lon_break < 0) { lon_dir = -1; lon_break += 180; }
jbe@0 523 else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; }
jbe@0 524 else lon_dir = 0;
jbe@0 525 /* get longitude of point */
jbe@0 526 lon0 = point->lon;
jbe@0 527 /* consider longitude wrap-around for point */
jbe@0 528 if (lon_dir < 0 && lon0 > lon_break) lon0 = pgl_round(lon0 - 360);
jbe@0 529 else if (lon_dir > 0 && lon0 < lon_break) lon0 = pgl_round(lon0 + 360);
jbe@0 530 /* iterate over all edges and vertices */
jbe@0 531 for (j=0; j<npoints; j++) {
jbe@0 532 /* return true if point is on vertex of polygon */
jbe@0 533 if (pgl_point_cmp(point, &(points[j])) == 0) return true;
jbe@0 534 /* calculate index of next vertex */
jbe@0 535 k = (j+1) % npoints;
jbe@0 536 /* skip last edge unless entry is (closed) outline or polygon */
jbe@0 537 if (
jbe@0 538 k == 0 &&
jbe@0 539 entrytype != PGL_ENTRY_OUTLINE &&
jbe@0 540 entrytype != PGL_ENTRY_POLYGON
jbe@0 541 ) continue;
jbe@0 542 /* get latitude and longitude values of edge */
jbe@0 543 lat1 = points[j].lat;
jbe@0 544 lat2 = points[k].lat;
jbe@0 545 lon1 = points[j].lon;
jbe@0 546 lon2 = points[k].lon;
jbe@0 547 /* consider longitude wrap-around for edge */
jbe@0 548 if (lon_dir < 0 && lon1 > lon_break) lon1 = pgl_round(lon1 - 360);
jbe@0 549 else if (lon_dir > 0 && lon1 < lon_break) lon1 = pgl_round(lon1 + 360);
jbe@0 550 if (lon_dir < 0 && lon2 > lon_break) lon2 = pgl_round(lon2 - 360);
jbe@0 551 else if (lon_dir > 0 && lon2 < lon_break) lon2 = pgl_round(lon2 + 360);
jbe@0 552 /* return true if point is on horizontal (west to east) edge of polygon */
jbe@0 553 if (
jbe@0 554 lat0 == lat1 && lat0 == lat2 &&
jbe@0 555 ( (lon0 >= lon1 && lon0 <= lon2) || (lon0 >= lon2 && lon0 <= lon1) )
jbe@0 556 ) return true;
jbe@0 557 /* check if edge crosses east/west line of point */
jbe@0 558 if ((lat1 < lat0 && lat2 >= lat0) || (lat2 < lat0 && lat1 >= lat0)) {
jbe@0 559 /* calculate longitude of intersection */
jbe@0 560 lon = (lon1 * (lat2-lat0) + lon2 * (lat0-lat1)) / (lat2-lat1);
jbe@0 561 /* return true if intersection goes (approximately) through point */
jbe@0 562 if (pgl_round(lon) == lon0) return true;
jbe@0 563 /* count intersection if east of point and entry is polygon*/
jbe@0 564 if (entrytype == PGL_ENTRY_POLYGON && lon > lon0) counter++;
jbe@0 565 }
jbe@0 566 }
jbe@0 567 }
jbe@0 568 /* return true if number of intersections is odd */
jbe@0 569 return counter & 1;
jbe@0 570 }
jbe@0 571
jbe@0 572 /* calculate (approximate) distance between point and cluster */
jbe@0 573 static double pgl_point_cluster_distance(pgl_point *point, pgl_cluster *cluster) {
jbe@0 574 int i, j, k; /* i: entry, j: point in entry, k: next point in entry */
jbe@0 575 int entrytype; /* type of entry */
jbe@0 576 int npoints; /* number of points in entry */
jbe@0 577 pgl_point *points; /* array of points in entry */
jbe@0 578 int lon_dir = 0; /* first vertex west (-1) or east (+1) */
jbe@0 579 double lon_break = 0; /* antipodal longitude of first vertex */
jbe@0 580 double lon_min = 0; /* minimum (adjusted) longitude of entry vertices */
jbe@0 581 double lon_max = 0; /* maximum (adjusted) longitude of entry vertices */
jbe@0 582 double lat0 = point->lat; /* latitude of point */
jbe@0 583 double lon0; /* (adjusted) longitude of point */
jbe@0 584 double lat1, lon1; /* latitude and (adjusted) longitude of vertex */
jbe@0 585 double lat2, lon2; /* latitude and (adjusted) longitude of next vertex */
jbe@0 586 double s; /* scalar for vector calculations */
jbe@0 587 double dist; /* distance calculated in one step */
jbe@0 588 double min_dist = INFINITY; /* minimum distance */
jbe@0 589 /* distance is zero if point is contained in cluster */
jbe@0 590 if (pgl_point_in_cluster(point, cluster)) return 0;
jbe@0 591 /* iterate over all entries */
jbe@0 592 for (i=0; i<cluster->nentries; i++) {
jbe@0 593 /* get properties of entry */
jbe@0 594 entrytype = cluster->entries[i].entrytype;
jbe@0 595 npoints = cluster->entries[i].npoints;
jbe@0 596 points = PGL_ENTRY_POINTS(cluster, i);
jbe@0 597 /* determine east/west orientation of first point of entry and calculate
jbe@0 598 antipodal longitude */
jbe@0 599 lon_break = points[0].lon;
jbe@0 600 if (lon_break < 0) { lon_dir = -1; lon_break += 180; }
jbe@0 601 else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; }
jbe@0 602 else lon_dir = 0;
jbe@0 603 /* determine covered longitude range */
jbe@0 604 for (j=0; j<npoints; j++) {
jbe@0 605 /* get longitude of vertex */
jbe@0 606 lon1 = points[j].lon;
jbe@0 607 /* adjust longitude to fix potential wrap-around */
jbe@0 608 if (lon_dir < 0 && lon1 > lon_break) lon1 -= 360;
jbe@0 609 else if (lon_dir > 0 && lon1 < lon_break) lon1 += 360;
jbe@0 610 /* update minimum and maximum longitude of polygon */
jbe@0 611 if (j == 0 || lon1 < lon_min) lon_min = lon1;
jbe@0 612 if (j == 0 || lon1 > lon_max) lon_max = lon1;
jbe@0 613 }
jbe@0 614 /* adjust longitude wrap-around according to full longitude range */
jbe@0 615 lon_break = (lon_max + lon_min) / 2;
jbe@0 616 if (lon_break < 0) { lon_dir = -1; lon_break += 180; }
jbe@0 617 else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; }
jbe@0 618 /* get longitude of point */
jbe@0 619 lon0 = point->lon;
jbe@0 620 /* consider longitude wrap-around for point */
jbe@0 621 if (lon_dir < 0 && lon0 > lon_break) lon0 -= 360;
jbe@0 622 else if (lon_dir > 0 && lon0 < lon_break) lon0 += 360;
jbe@0 623 /* iterate over all edges and vertices */
jbe@0 624 for (j=0; j<npoints; j++) {
jbe@0 625 /* get latitude and longitude values of current point */
jbe@0 626 lat1 = points[j].lat;
jbe@0 627 lon1 = points[j].lon;
jbe@0 628 /* consider longitude wrap-around for current point */
jbe@0 629 if (lon_dir < 0 && lon1 > lon_break) lon1 -= 360;
jbe@0 630 else if (lon_dir > 0 && lon1 < lon_break) lon1 += 360;
jbe@0 631 /* calculate distance to vertex */
jbe@0 632 dist = pgl_distance(lat0, lon0, lat1, lon1);
jbe@0 633 /* store calculated distance if smallest */
jbe@0 634 if (dist < min_dist) min_dist = dist;
jbe@0 635 /* calculate index of next vertex */
jbe@0 636 k = (j+1) % npoints;
jbe@0 637 /* skip last edge unless entry is (closed) outline or polygon */
jbe@0 638 if (
jbe@0 639 k == 0 &&
jbe@0 640 entrytype != PGL_ENTRY_OUTLINE &&
jbe@0 641 entrytype != PGL_ENTRY_POLYGON
jbe@0 642 ) continue;
jbe@0 643 /* get latitude and longitude values of next point */
jbe@0 644 lat2 = points[k].lat;
jbe@0 645 lon2 = points[k].lon;
jbe@0 646 /* consider longitude wrap-around for next point */
jbe@0 647 if (lon_dir < 0 && lon2 > lon_break) lon2 -= 360;
jbe@0 648 else if (lon_dir > 0 && lon2 < lon_break) lon2 += 360;
jbe@0 649 /* go to next vertex and edge if edge is degenerated */
jbe@0 650 if (lat1 == lat2 && lon1 == lon2) continue;
jbe@0 651 /* otherwise test if point can be projected onto edge of polygon */
jbe@0 652 s = (
jbe@0 653 ((lat0-lat1) * (lat2-lat1) + (lon0-lon1) * (lon2-lon1)) /
jbe@0 654 ((lat2-lat1) * (lat2-lat1) + (lon2-lon1) * (lon2-lon1))
jbe@0 655 );
jbe@0 656 /* go to next vertex and edge if point cannot be projected */
jbe@0 657 if (!(s > 0 && s < 1)) continue;
jbe@0 658 /* calculate distance from original point to projected point */
jbe@0 659 dist = pgl_distance(
jbe@0 660 lat0, lon0,
jbe@0 661 lat1 + s * (lat2-lat1),
jbe@0 662 lon1 + s * (lon2-lon1)
jbe@0 663 );
jbe@0 664 /* store calculated distance if smallest */
jbe@0 665 if (dist < min_dist) min_dist = dist;
jbe@0 666 }
jbe@0 667 }
jbe@0 668 /* return minimum distance */
jbe@0 669 return min_dist;
jbe@0 670 }
jbe@0 671
jbe@0 672 /* estimator function for distance between box and point */
jbe@0 673 /* allowed to return smaller values than actually correct */
jbe@0 674 static double pgl_estimate_point_box_distance(pgl_point *point, pgl_box *box) {
jbe@0 675 double dlon; /* longitude range of box (delta longitude) */
jbe@0 676 double h; /* half of distance along meridian */
jbe@0 677 double d; /* distance between both southern or both northern points */
jbe@0 678 double cur_dist; /* calculated distance */
jbe@0 679 double min_dist; /* minimum distance calculated */
jbe@0 680 /* return infinity if bounding box is empty */
jbe@0 681 if (box->lat_min > box->lat_max) return INFINITY;
jbe@0 682 /* return zero if point is inside bounding box */
jbe@0 683 if (pgl_point_in_box(point, box)) return 0;
jbe@0 684 /* calculate delta longitude */
jbe@0 685 dlon = box->lon_max - box->lon_min;
jbe@0 686 if (dlon < 0) dlon += 360; /* 180th meridian crossed */
jbe@0 687 /* if delta longitude is greater than 180 degrees, perform safe fall-back */
jbe@0 688 if (dlon > 180) return 0;
jbe@0 689 /* calculate half of distance along meridian */
jbe@0 690 h = pgl_distance(box->lat_min, 0, box->lat_max, 0) / 2;
jbe@0 691 /* calculate full distance between southern points */
jbe@0 692 d = pgl_distance(box->lat_min, 0, box->lat_min, dlon);
jbe@0 693 /* calculate maximum of full distance and half distance */
jbe@0 694 if (h > d) d = h;
jbe@0 695 /* calculate distance from point to first southern vertex and substract
jbe@0 696 maximum error */
jbe@0 697 min_dist = pgl_distance(
jbe@0 698 point->lat, point->lon, box->lat_min, box->lon_min
jbe@0 699 ) - d;
jbe@0 700 /* return zero if estimated distance is smaller than zero */
jbe@0 701 if (min_dist <= 0) return 0;
jbe@0 702 /* repeat procedure with second southern vertex */
jbe@0 703 cur_dist = pgl_distance(
jbe@0 704 point->lat, point->lon, box->lat_min, box->lon_max
jbe@0 705 ) - d;
jbe@0 706 if (cur_dist <= 0) return 0;
jbe@0 707 if (cur_dist < min_dist) min_dist = cur_dist;
jbe@0 708 /* calculate full distance between northern points */
jbe@0 709 d = pgl_distance(box->lat_max, 0, box->lat_max, dlon);
jbe@0 710 /* calculate maximum of full distance and half distance */
jbe@0 711 if (h > d) d = h;
jbe@0 712 /* repeat procedure with northern vertices */
jbe@0 713 cur_dist = pgl_distance(
jbe@0 714 point->lat, point->lon, box->lat_max, box->lon_max
jbe@0 715 ) - d;
jbe@0 716 if (cur_dist <= 0) return 0;
jbe@0 717 if (cur_dist < min_dist) min_dist = cur_dist;
jbe@0 718 cur_dist = pgl_distance(
jbe@0 719 point->lat, point->lon, box->lat_max, box->lon_min
jbe@0 720 ) - d;
jbe@0 721 if (cur_dist <= 0) return 0;
jbe@0 722 if (cur_dist < min_dist) min_dist = cur_dist;
jbe@0 723 /* return smallest value (unless already returned zero) */
jbe@0 724 return min_dist;
jbe@0 725 }
jbe@0 726
jbe@0 727
jbe@0 728 /*----------------------------*
jbe@0 729 * fractal geographic index *
jbe@0 730 *----------------------------*/
jbe@0 731
jbe@0 732 /* number of bytes used for geographic (center) position in keys */
jbe@0 733 #define PGL_KEY_LATLON_BYTELEN 7
jbe@0 734
jbe@0 735 /* maximum reference value for logarithmic size of geographic objects */
jbe@0 736 #define PGL_AREAKEY_REFOBJSIZE (PGL_DIAMETER/3.0) /* can be tweaked */
jbe@0 737
jbe@0 738 /* safety margin to avoid floating point errors in distance estimation */
jbe@0 739 #define PGL_FPE_SAFETY (1.0+1e-14) /* slightly greater than 1.0 */
jbe@0 740
jbe@0 741 /* pointer to index key (either pgl_pointkey or pgl_areakey) */
jbe@0 742 typedef unsigned char *pgl_keyptr;
jbe@0 743
jbe@0 744 /* index key for points (objects with zero area) on the spheroid */
jbe@0 745 /* bit 0..55: interspersed bits of latitude and longitude,
jbe@0 746 bit 56..57: always zero,
jbe@0 747 bit 58..63: node depth in hypothetic (full) tree from 0 to 56 (incl.) */
jbe@0 748 typedef unsigned char pgl_pointkey[PGL_KEY_LATLON_BYTELEN+1];
jbe@0 749
jbe@0 750 /* index key for geographic objects on spheroid with area greater than zero */
jbe@0 751 /* bit 0..55: interspersed bits of latitude and longitude of center point,
jbe@0 752 bit 56: always set to 1,
jbe@0 753 bit 57..63: node depth in hypothetic (full) tree from 0 to (2*56)+1 (incl.),
jbe@0 754 bit 64..71: logarithmic object size from 0 to 56+1 = 57 (incl.), but set to
jbe@0 755 PGL_KEY_OBJSIZE_EMPTY (with interspersed bits = 0 and node depth
jbe@0 756 = 113) for empty objects, and set to PGL_KEY_OBJSIZE_UNIVERSAL
jbe@0 757 (with interspersed bits = 0 and node depth = 0) for keys which
jbe@0 758 cover both empty and non-empty objects */
jbe@0 759
jbe@0 760 typedef unsigned char pgl_areakey[PGL_KEY_LATLON_BYTELEN+2];
jbe@0 761
jbe@0 762 /* helper macros for reading/writing index keys */
jbe@0 763 #define PGL_KEY_NODEDEPTH_OFFSET PGL_KEY_LATLON_BYTELEN
jbe@0 764 #define PGL_KEY_OBJSIZE_OFFSET (PGL_KEY_NODEDEPTH_OFFSET+1)
jbe@0 765 #define PGL_POINTKEY_MAXDEPTH (PGL_KEY_LATLON_BYTELEN*8)
jbe@0 766 #define PGL_AREAKEY_MAXDEPTH (2*PGL_POINTKEY_MAXDEPTH+1)
jbe@0 767 #define PGL_AREAKEY_MAXOBJSIZE (PGL_POINTKEY_MAXDEPTH+1)
jbe@0 768 #define PGL_AREAKEY_TYPEMASK 0x80
jbe@0 769 #define PGL_KEY_LATLONBIT(key, n) ((key)[(n)/8] & (0x80 >> ((n)%8)))
jbe@0 770 #define PGL_KEY_LATLONBIT_DIFF(key1, key2, n) \
jbe@0 771 ( PGL_KEY_LATLONBIT(key1, n) ^ \
jbe@0 772 PGL_KEY_LATLONBIT(key2, n) )
jbe@0 773 #define PGL_KEY_IS_AREAKEY(key) ((key)[PGL_KEY_NODEDEPTH_OFFSET] & \
jbe@0 774 PGL_AREAKEY_TYPEMASK)
jbe@0 775 #define PGL_KEY_NODEDEPTH(key) ((key)[PGL_KEY_NODEDEPTH_OFFSET] & \
jbe@0 776 (PGL_AREAKEY_TYPEMASK-1))
jbe@0 777 #define PGL_KEY_OBJSIZE(key) ((key)[PGL_KEY_OBJSIZE_OFFSET])
jbe@0 778 #define PGL_KEY_OBJSIZE_EMPTY 126
jbe@0 779 #define PGL_KEY_OBJSIZE_UNIVERSAL 127
jbe@0 780 #define PGL_KEY_IS_EMPTY(key) ( PGL_KEY_IS_AREAKEY(key) && \
jbe@0 781 (key)[PGL_KEY_OBJSIZE_OFFSET] == \
jbe@0 782 PGL_KEY_OBJSIZE_EMPTY )
jbe@0 783 #define PGL_KEY_IS_UNIVERSAL(key) ( PGL_KEY_IS_AREAKEY(key) && \
jbe@0 784 (key)[PGL_KEY_OBJSIZE_OFFSET] == \
jbe@0 785 PGL_KEY_OBJSIZE_UNIVERSAL )
jbe@0 786
jbe@0 787 /* set area key to match empty objects only */
jbe@0 788 static void pgl_key_set_empty(pgl_keyptr key) {
jbe@0 789 memset(key, 0, sizeof(pgl_areakey));
jbe@0 790 /* Note: setting node depth to maximum is required for picksplit function */
jbe@0 791 key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | PGL_AREAKEY_MAXDEPTH;
jbe@0 792 key[PGL_KEY_OBJSIZE_OFFSET] = PGL_KEY_OBJSIZE_EMPTY;
jbe@0 793 }
jbe@0 794
jbe@0 795 /* set area key to match any object (including empty objects) */
jbe@0 796 static void pgl_key_set_universal(pgl_keyptr key) {
jbe@0 797 memset(key, 0, sizeof(pgl_areakey));
jbe@0 798 key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK;
jbe@0 799 key[PGL_KEY_OBJSIZE_OFFSET] = PGL_KEY_OBJSIZE_UNIVERSAL;
jbe@0 800 }
jbe@0 801
jbe@0 802 /* convert a point on earth into a max-depth key to be used in index */
jbe@0 803 static void pgl_point_to_key(pgl_point *point, pgl_keyptr key) {
jbe@0 804 double lat = point->lat;
jbe@0 805 double lon = point->lon;
jbe@0 806 int i;
jbe@0 807 /* clear latitude and longitude bits */
jbe@0 808 memset(key, 0, PGL_KEY_LATLON_BYTELEN);
jbe@0 809 /* set node depth to maximum and type bit to zero */
jbe@0 810 key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_POINTKEY_MAXDEPTH;
jbe@0 811 /* iterate over all latitude/longitude bit pairs */
jbe@0 812 for (i=0; i<PGL_POINTKEY_MAXDEPTH/2; i++) {
jbe@0 813 /* determine latitude bit */
jbe@0 814 if (lat >= 0) {
jbe@0 815 key[i/4] |= 0x80 >> (2*(i%4));
jbe@0 816 lat *= 2; lat -= 90;
jbe@0 817 } else {
jbe@0 818 lat *= 2; lat += 90;
jbe@0 819 }
jbe@0 820 /* determine longitude bit */
jbe@0 821 if (lon >= 0) {
jbe@0 822 key[i/4] |= 0x80 >> (2*(i%4)+1);
jbe@0 823 lon *= 2; lon -= 180;
jbe@0 824 } else {
jbe@0 825 lon *= 2; lon += 180;
jbe@0 826 }
jbe@0 827 }
jbe@0 828 }
jbe@0 829
jbe@0 830 /* convert a circle on earth into a max-depth key to be used in an index */
jbe@0 831 static void pgl_circle_to_key(pgl_circle *circle, pgl_keyptr key) {
jbe@0 832 /* handle special case of empty circle */
jbe@0 833 if (circle->radius < 0) {
jbe@0 834 pgl_key_set_empty(key);
jbe@0 835 return;
jbe@0 836 }
jbe@0 837 /* perform same action as for point keys */
jbe@0 838 pgl_point_to_key(&(circle->center), key);
jbe@0 839 /* but overwrite type and node depth to fit area index key */
jbe@0 840 key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | PGL_AREAKEY_MAXDEPTH;
jbe@0 841 /* check if radius is greater than (or equal to) reference size */
jbe@0 842 /* (treat equal values as greater values for numerical safety) */
jbe@0 843 if (circle->radius >= PGL_AREAKEY_REFOBJSIZE) {
jbe@0 844 /* if yes, set logarithmic size to zero */
jbe@0 845 key[PGL_KEY_OBJSIZE_OFFSET] = 0;
jbe@0 846 } else {
jbe@0 847 /* otherwise, determine logarithmic size iteratively */
jbe@0 848 /* (one step is equivalent to a factor of sqrt(2)) */
jbe@0 849 double reference = PGL_AREAKEY_REFOBJSIZE / M_SQRT2;
jbe@0 850 int objsize = 1;
jbe@0 851 while (objsize < PGL_AREAKEY_MAXOBJSIZE) {
jbe@0 852 /* stop when radius is greater than (or equal to) adjusted reference */
jbe@0 853 /* (treat equal values as greater values for numerical safety) */
jbe@0 854 if (circle->radius >= reference) break;
jbe@0 855 reference /= M_SQRT2;
jbe@0 856 objsize++;
jbe@0 857 }
jbe@0 858 /* set logarithmic size to determined value */
jbe@0 859 key[PGL_KEY_OBJSIZE_OFFSET] = objsize;
jbe@0 860 }
jbe@0 861 }
jbe@0 862
jbe@0 863 /* check if one key is subkey of another key or vice versa */
jbe@0 864 static bool pgl_keys_overlap(pgl_keyptr key1, pgl_keyptr key2) {
jbe@0 865 int i; /* key bit offset (includes both lat/lon and log. obj. size bits) */
jbe@0 866 /* determine smallest depth */
jbe@0 867 int depth1 = PGL_KEY_NODEDEPTH(key1);
jbe@0 868 int depth2 = PGL_KEY_NODEDEPTH(key2);
jbe@0 869 int depth = (depth1 < depth2) ? depth1 : depth2;
jbe@0 870 /* check if keys are area keys (assuming that both keys have same type) */
jbe@0 871 if (PGL_KEY_IS_AREAKEY(key1)) {
jbe@0 872 int j = 0; /* bit offset for logarithmic object size bits */
jbe@0 873 int k = 0; /* bit offset for latitude and longitude */
jbe@0 874 /* fetch logarithmic object size information */
jbe@0 875 int objsize1 = PGL_KEY_OBJSIZE(key1);
jbe@0 876 int objsize2 = PGL_KEY_OBJSIZE(key2);
jbe@0 877 /* handle special cases for empty objects (universal and empty keys) */
jbe@0 878 if (
jbe@0 879 objsize1 == PGL_KEY_OBJSIZE_UNIVERSAL ||
jbe@0 880 objsize2 == PGL_KEY_OBJSIZE_UNIVERSAL
jbe@0 881 ) return true;
jbe@0 882 if (
jbe@0 883 objsize1 == PGL_KEY_OBJSIZE_EMPTY ||
jbe@0 884 objsize2 == PGL_KEY_OBJSIZE_EMPTY
jbe@0 885 ) return objsize1 == objsize2;
jbe@0 886 /* iterate through key bits */
jbe@0 887 for (i=0; i<depth; i++) {
jbe@0 888 /* every second bit is a bit describing the object size */
jbe@0 889 if (i%2 == 0) {
jbe@0 890 /* check if object size bit is different in both keys (objsize1 and
jbe@0 891 objsize2 describe the minimum index when object size bit is set) */
jbe@0 892 if (
jbe@0 893 (objsize1 <= j && objsize2 > j) ||
jbe@0 894 (objsize2 <= j && objsize1 > j)
jbe@0 895 ) {
jbe@0 896 /* bit differs, therefore keys are in separate branches */
jbe@0 897 return false;
jbe@0 898 }
jbe@0 899 /* increase bit counter for object size bits */
jbe@0 900 j++;
jbe@0 901 }
jbe@0 902 /* all other bits describe latitude and longitude */
jbe@0 903 else {
jbe@0 904 /* check if bit differs in both keys */
jbe@0 905 if (PGL_KEY_LATLONBIT_DIFF(key1, key2, k)) {
jbe@0 906 /* bit differs, therefore keys are in separate branches */
jbe@0 907 return false;
jbe@0 908 }
jbe@0 909 /* increase bit counter for latitude/longitude bits */
jbe@0 910 k++;
jbe@0 911 }
jbe@0 912 }
jbe@0 913 }
jbe@0 914 /* if not, keys are point keys */
jbe@0 915 else {
jbe@0 916 /* iterate through key bits */
jbe@0 917 for (i=0; i<depth; i++) {
jbe@0 918 /* check if bit differs in both keys */
jbe@0 919 if (PGL_KEY_LATLONBIT_DIFF(key1, key2, i)) {
jbe@0 920 /* bit differs, therefore keys are in separate branches */
jbe@0 921 return false;
jbe@0 922 }
jbe@0 923 }
jbe@0 924 }
jbe@0 925 /* return true because keys are in the same branch */
jbe@0 926 return true;
jbe@0 927 }
jbe@0 928
jbe@0 929 /* combine two keys into new key which covers both original keys */
jbe@0 930 /* (result stored in first argument) */
jbe@0 931 static void pgl_unite_keys(pgl_keyptr dst, pgl_keyptr src) {
jbe@0 932 int i; /* key bit offset (includes both lat/lon and log. obj. size bits) */
jbe@0 933 /* determine smallest depth */
jbe@0 934 int depth1 = PGL_KEY_NODEDEPTH(dst);
jbe@0 935 int depth2 = PGL_KEY_NODEDEPTH(src);
jbe@0 936 int depth = (depth1 < depth2) ? depth1 : depth2;
jbe@0 937 /* check if keys are area keys (assuming that both keys have same type) */
jbe@0 938 if (PGL_KEY_IS_AREAKEY(dst)) {
jbe@0 939 pgl_areakey dstbuf = { 0, }; /* destination buffer (cleared) */
jbe@0 940 int j = 0; /* bit offset for logarithmic object size bits */
jbe@0 941 int k = 0; /* bit offset for latitude and longitude */
jbe@0 942 /* fetch logarithmic object size information */
jbe@0 943 int objsize1 = PGL_KEY_OBJSIZE(dst);
jbe@0 944 int objsize2 = PGL_KEY_OBJSIZE(src);
jbe@0 945 /* handle special cases for empty objects (universal and empty keys) */
jbe@0 946 if (
jbe@0 947 objsize1 > PGL_AREAKEY_MAXOBJSIZE ||
jbe@0 948 objsize2 > PGL_AREAKEY_MAXOBJSIZE
jbe@0 949 ) {
jbe@0 950 if (
jbe@0 951 objsize1 == PGL_KEY_OBJSIZE_EMPTY &&
jbe@0 952 objsize2 == PGL_KEY_OBJSIZE_EMPTY
jbe@0 953 ) pgl_key_set_empty(dst);
jbe@0 954 else pgl_key_set_universal(dst);
jbe@0 955 return;
jbe@0 956 }
jbe@0 957 /* iterate through key bits */
jbe@0 958 for (i=0; i<depth; i++) {
jbe@0 959 /* every second bit is a bit describing the object size */
jbe@0 960 if (i%2 == 0) {
jbe@0 961 /* increase bit counter for object size bits first */
jbe@0 962 /* (handy when setting objsize variable) */
jbe@0 963 j++;
jbe@0 964 /* check if object size bit is set in neither key */
jbe@0 965 if (objsize1 >= j && objsize2 >= j) {
jbe@0 966 /* set objsize in destination buffer to indicate that size bit is
jbe@0 967 unset in destination buffer at the current bit position */
jbe@0 968 dstbuf[PGL_KEY_OBJSIZE_OFFSET] = j;
jbe@0 969 }
jbe@0 970 /* break if object size bit is set in one key only */
jbe@0 971 else if (objsize1 >= j || objsize2 >= j) break;
jbe@0 972 }
jbe@0 973 /* all other bits describe latitude and longitude */
jbe@0 974 else {
jbe@0 975 /* break if bit differs in both keys */
jbe@0 976 if (PGL_KEY_LATLONBIT(dst, k)) {
jbe@0 977 if (!PGL_KEY_LATLONBIT(src, k)) break;
jbe@0 978 /* but set bit in destination buffer if bit is set in both keys */
jbe@0 979 dstbuf[k/8] |= 0x80 >> (k%8);
jbe@0 980 } else if (PGL_KEY_LATLONBIT(src, k)) break;
jbe@0 981 /* increase bit counter for latitude/longitude bits */
jbe@0 982 k++;
jbe@0 983 }
jbe@0 984 }
jbe@0 985 /* set common node depth and type bit (type bit = 1) */
jbe@0 986 dstbuf[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | i;
jbe@0 987 /* copy contents of destination buffer to first key */
jbe@0 988 memcpy(dst, dstbuf, sizeof(pgl_areakey));
jbe@0 989 }
jbe@0 990 /* if not, keys are point keys */
jbe@0 991 else {
jbe@0 992 pgl_pointkey dstbuf = { 0, }; /* destination buffer (cleared) */
jbe@0 993 /* iterate through key bits */
jbe@0 994 for (i=0; i<depth; i++) {
jbe@0 995 /* break if bit differs in both keys */
jbe@0 996 if (PGL_KEY_LATLONBIT(dst, i)) {
jbe@0 997 if (!PGL_KEY_LATLONBIT(src, i)) break;
jbe@0 998 /* but set bit in destination buffer if bit is set in both keys */
jbe@0 999 dstbuf[i/8] |= 0x80 >> (i%8);
jbe@0 1000 } else if (PGL_KEY_LATLONBIT(src, i)) break;
jbe@0 1001 }
jbe@0 1002 /* set common node depth (type bit = 0) */
jbe@0 1003 dstbuf[PGL_KEY_NODEDEPTH_OFFSET] = i;
jbe@0 1004 /* copy contents of destination buffer to first key */
jbe@0 1005 memcpy(dst, dstbuf, sizeof(pgl_pointkey));
jbe@0 1006 }
jbe@0 1007 }
jbe@0 1008
jbe@0 1009 /* determine center(!) boundaries and radius estimation of index key */
jbe@0 1010 static double pgl_key_to_box(pgl_keyptr key, pgl_box *box) {
jbe@0 1011 int i;
jbe@0 1012 /* determine node depth */
jbe@0 1013 int depth = PGL_KEY_NODEDEPTH(key);
jbe@0 1014 /* center point of possible result */
jbe@0 1015 double lat = 0;
jbe@0 1016 double lon = 0;
jbe@0 1017 /* maximum distance of real center point from key center */
jbe@0 1018 double dlat = 90;
jbe@0 1019 double dlon = 180;
jbe@0 1020 /* maximum radius of contained objects */
jbe@0 1021 double radius = 0; /* always return zero for point index keys */
jbe@0 1022 /* check if key is area key */
jbe@0 1023 if (PGL_KEY_IS_AREAKEY(key)) {
jbe@0 1024 /* get logarithmic object size */
jbe@0 1025 int objsize = PGL_KEY_OBJSIZE(key);
jbe@0 1026 /* handle special cases for empty objects (universal and empty keys) */
jbe@0 1027 if (objsize == PGL_KEY_OBJSIZE_EMPTY) {
jbe@0 1028 pgl_box_set_empty(box);
jbe@0 1029 return 0;
jbe@0 1030 } else if (objsize == PGL_KEY_OBJSIZE_UNIVERSAL) {
jbe@0 1031 box->lat_min = -90;
jbe@0 1032 box->lat_max = 90;
jbe@0 1033 box->lon_min = -180;
jbe@0 1034 box->lon_max = 180;
jbe@0 1035 return 0; /* any value >= 0 would do */
jbe@0 1036 }
jbe@0 1037 /* calculate maximum possible radius of objects covered by the given key */
jbe@0 1038 if (objsize == 0) radius = INFINITY;
jbe@0 1039 else {
jbe@0 1040 radius = PGL_AREAKEY_REFOBJSIZE;
jbe@0 1041 while (--objsize) radius /= M_SQRT2;
jbe@0 1042 }
jbe@0 1043 /* iterate over latitude and longitude bits in key */
jbe@0 1044 /* (every second bit is a latitude or longitude bit) */
jbe@0 1045 for (i=0; i<depth/2; i++) {
jbe@0 1046 /* check if latitude bit */
jbe@0 1047 if (i%2 == 0) {
jbe@0 1048 /* cut latitude dimension in half */
jbe@0 1049 dlat /= 2;
jbe@0 1050 /* increase center latitude if bit is 1, otherwise decrease */
jbe@0 1051 if (PGL_KEY_LATLONBIT(key, i)) lat += dlat;
jbe@0 1052 else lat -= dlat;
jbe@0 1053 }
jbe@0 1054 /* otherwise longitude bit */
jbe@0 1055 else {
jbe@0 1056 /* cut longitude dimension in half */
jbe@0 1057 dlon /= 2;
jbe@0 1058 /* increase center longitude if bit is 1, otherwise decrease */
jbe@0 1059 if (PGL_KEY_LATLONBIT(key, i)) lon += dlon;
jbe@0 1060 else lon -= dlon;
jbe@0 1061 }
jbe@0 1062 }
jbe@0 1063 }
jbe@0 1064 /* if not, keys are point keys */
jbe@0 1065 else {
jbe@0 1066 /* iterate over all bits in key */
jbe@0 1067 for (i=0; i<depth; i++) {
jbe@0 1068 /* check if latitude bit */
jbe@0 1069 if (i%2 == 0) {
jbe@0 1070 /* cut latitude dimension in half */
jbe@0 1071 dlat /= 2;
jbe@0 1072 /* increase center latitude if bit is 1, otherwise decrease */
jbe@0 1073 if (PGL_KEY_LATLONBIT(key, i)) lat += dlat;
jbe@0 1074 else lat -= dlat;
jbe@0 1075 }
jbe@0 1076 /* otherwise longitude bit */
jbe@0 1077 else {
jbe@0 1078 /* cut longitude dimension in half */
jbe@0 1079 dlon /= 2;
jbe@0 1080 /* increase center longitude if bit is 1, otherwise decrease */
jbe@0 1081 if (PGL_KEY_LATLONBIT(key, i)) lon += dlon;
jbe@0 1082 else lon -= dlon;
jbe@0 1083 }
jbe@0 1084 }
jbe@0 1085 }
jbe@0 1086 /* calculate boundaries from center point and remaining dlat and dlon */
jbe@0 1087 /* (return values through pointer to box) */
jbe@0 1088 box->lat_min = lat - dlat;
jbe@0 1089 box->lat_max = lat + dlat;
jbe@0 1090 box->lon_min = lon - dlon;
jbe@0 1091 box->lon_max = lon + dlon;
jbe@0 1092 /* return radius (as a function return value) */
jbe@0 1093 return radius;
jbe@0 1094 }
jbe@0 1095
jbe@0 1096 /* estimator function for distance between point and index key */
jbe@0 1097 /* allowed to return smaller values than actually correct */
jbe@0 1098 static double pgl_estimate_key_distance(pgl_keyptr key, pgl_point *point) {
jbe@0 1099 pgl_box box; /* center(!) bounding box of area index key */
jbe@0 1100 /* calculate center(!) bounding box and maximum radius of objects covered
jbe@0 1101 by area index key (radius is zero for point index keys) */
jbe@0 1102 double distance = pgl_key_to_box(key, &box);
jbe@0 1103 /* calculate estimated distance between bounding box of center point of
jbe@0 1104 indexed object and point passed as second argument, then substract maximum
jbe@0 1105 radius of objects covered by index key */
jbe@0 1106 /* (use PGL_FPE_SAFETY factor to cope with minor floating point errors) */
jbe@0 1107 distance = (
jbe@0 1108 pgl_estimate_point_box_distance(point, &box) / PGL_FPE_SAFETY -
jbe@0 1109 distance * PGL_FPE_SAFETY
jbe@0 1110 );
jbe@0 1111 /* truncate negative results to zero */
jbe@0 1112 if (distance <= 0) distance = 0;
jbe@0 1113 /* return result */
jbe@0 1114 return distance;
jbe@0 1115 }
jbe@0 1116
jbe@0 1117
jbe@0 1118 /*---------------------------------*
jbe@0 1119 * helper functions for text I/O *
jbe@0 1120 *---------------------------------*/
jbe@0 1121
jbe@0 1122 #define PGL_NUMBUFLEN 64 /* buffer size for number to string conversion */
jbe@0 1123
jbe@0 1124 /* convert floating point number to string (round-trip safe) */
jbe@0 1125 static void pgl_print_float(char *buf, double flt) {
jbe@0 1126 /* check if number is integral */
jbe@0 1127 if (trunc(flt) == flt) {
jbe@0 1128 /* for integral floats use maximum precision */
jbe@0 1129 snprintf(buf, PGL_NUMBUFLEN, "%.17g", flt);
jbe@0 1130 } else {
jbe@0 1131 /* otherwise check if 15, 16, or 17 digits needed (round-trip safety) */
jbe@0 1132 snprintf(buf, PGL_NUMBUFLEN, "%.15g", flt);
jbe@0 1133 if (strtod(buf, NULL) != flt) snprintf(buf, PGL_NUMBUFLEN, "%.16g", flt);
jbe@0 1134 if (strtod(buf, NULL) != flt) snprintf(buf, PGL_NUMBUFLEN, "%.17g", flt);
jbe@0 1135 }
jbe@0 1136 }
jbe@0 1137
jbe@0 1138 /* convert latitude floating point number (in degrees) to string */
jbe@0 1139 static void pgl_print_lat(char *buf, double lat) {
jbe@0 1140 if (signbit(lat)) {
jbe@0 1141 /* treat negative latitudes (including -0) as south */
jbe@0 1142 snprintf(buf, PGL_NUMBUFLEN, "S%015.12f", -lat);
jbe@0 1143 } else {
jbe@0 1144 /* treat positive latitudes (including +0) as north */
jbe@0 1145 snprintf(buf, PGL_NUMBUFLEN, "N%015.12f", lat);
jbe@0 1146 }
jbe@0 1147 }
jbe@0 1148
jbe@0 1149 /* convert longitude floating point number (in degrees) to string */
jbe@0 1150 static void pgl_print_lon(char *buf, double lon) {
jbe@0 1151 if (signbit(lon)) {
jbe@0 1152 /* treat negative longitudes (including -0) as west */
jbe@0 1153 snprintf(buf, PGL_NUMBUFLEN, "W%016.12f", -lon);
jbe@0 1154 } else {
jbe@0 1155 /* treat positive longitudes (including +0) as east */
jbe@0 1156 snprintf(buf, PGL_NUMBUFLEN, "E%016.12f", lon);
jbe@0 1157 }
jbe@0 1158 }
jbe@0 1159
jbe@0 1160 /* bit masks used as return value of pgl_scan() function */
jbe@0 1161 #define PGL_SCAN_NONE 0 /* no value has been parsed */
jbe@0 1162 #define PGL_SCAN_LAT (1<<0) /* latitude has been parsed */
jbe@0 1163 #define PGL_SCAN_LON (1<<1) /* longitude has been parsed */
jbe@0 1164 #define PGL_SCAN_LATLON (PGL_SCAN_LAT | PGL_SCAN_LON) /* bitwise OR of both */
jbe@0 1165
jbe@0 1166 /* parse a coordinate (can be latitude or longitude) */
jbe@0 1167 static int pgl_scan(char **str, double *lat, double *lon) {
jbe@0 1168 double val;
jbe@0 1169 int len;
jbe@0 1170 if (
jbe@0 1171 sscanf(*str, " N %lf %n", &val, &len) ||
jbe@0 1172 sscanf(*str, " n %lf %n", &val, &len)
jbe@0 1173 ) {
jbe@0 1174 *str += len; *lat = val; return PGL_SCAN_LAT;
jbe@0 1175 }
jbe@0 1176 if (
jbe@0 1177 sscanf(*str, " S %lf %n", &val, &len) ||
jbe@0 1178 sscanf(*str, " s %lf %n", &val, &len)
jbe@0 1179 ) {
jbe@0 1180 *str += len; *lat = -val; return PGL_SCAN_LAT;
jbe@0 1181 }
jbe@0 1182 if (
jbe@0 1183 sscanf(*str, " E %lf %n", &val, &len) ||
jbe@0 1184 sscanf(*str, " e %lf %n", &val, &len)
jbe@0 1185 ) {
jbe@0 1186 *str += len; *lon = val; return PGL_SCAN_LON;
jbe@0 1187 }
jbe@0 1188 if (
jbe@0 1189 sscanf(*str, " W %lf %n", &val, &len) ||
jbe@0 1190 sscanf(*str, " w %lf %n", &val, &len)
jbe@0 1191 ) {
jbe@0 1192 *str += len; *lon = -val; return PGL_SCAN_LON;
jbe@0 1193 }
jbe@0 1194 return PGL_SCAN_NONE;
jbe@0 1195 }
jbe@0 1196
jbe@0 1197
jbe@0 1198 /*-----------------*
jbe@0 1199 * SQL functions *
jbe@0 1200 *-----------------*/
jbe@0 1201
jbe@0 1202 /* Note: These function names use "epoint", "ebox", etc. notation here instead
jbe@0 1203 of "point", "box", etc. in order to distinguish them from any previously
jbe@0 1204 defined functions. */
jbe@0 1205
jbe@0 1206 /* function needed for dummy types and/or not implemented features */
jbe@0 1207 PG_FUNCTION_INFO_V1(pgl_notimpl);
jbe@0 1208 Datum pgl_notimpl(PG_FUNCTION_ARGS) {
jbe@0 1209 ereport(ERROR, (errmsg("not implemented by pgLatLon")));
jbe@0 1210 }
jbe@0 1211
jbe@0 1212 /* set point to latitude and longitude (including checks) */
jbe@0 1213 static void pgl_epoint_set_latlon(pgl_point *point, double lat, double lon) {
jbe@0 1214 /* reject infinite or NaN values */
jbe@0 1215 if (!isfinite(lat) || !isfinite(lon)) {
jbe@0 1216 ereport(ERROR, (
jbe@0 1217 errcode(ERRCODE_DATA_EXCEPTION),
jbe@0 1218 errmsg("epoint requires finite coordinates")
jbe@0 1219 ));
jbe@0 1220 }
jbe@0 1221 /* check latitude bounds */
jbe@0 1222 if (lat < -90) {
jbe@0 1223 ereport(WARNING, (errmsg("latitude exceeds south pole")));
jbe@0 1224 lat = -90;
jbe@0 1225 } else if (lat > 90) {
jbe@0 1226 ereport(WARNING, (errmsg("latitude exceeds north pole")));
jbe@0 1227 lat = 90;
jbe@0 1228 }
jbe@0 1229 /* check longitude bounds */
jbe@0 1230 if (lon < -180) {
jbe@0 1231 ereport(NOTICE, (errmsg("longitude west of 180th meridian normalized")));
jbe@0 1232 lon += 360 - trunc(lon / 360) * 360;
jbe@0 1233 } else if (lon > 180) {
jbe@0 1234 ereport(NOTICE, (errmsg("longitude east of 180th meridian normalized")));
jbe@0 1235 lon -= 360 + trunc(lon / 360) * 360;
jbe@0 1236 }
jbe@0 1237 /* store rounded latitude/longitude values for round-trip safety */
jbe@0 1238 point->lat = pgl_round(lat);
jbe@0 1239 point->lon = pgl_round(lon);
jbe@0 1240 }
jbe@0 1241
jbe@0 1242 /* create point ("epoint" in SQL) from latitude and longitude */
jbe@0 1243 PG_FUNCTION_INFO_V1(pgl_create_epoint);
jbe@0 1244 Datum pgl_create_epoint(PG_FUNCTION_ARGS) {
jbe@0 1245 pgl_point *point = (pgl_point *)palloc(sizeof(pgl_point));
jbe@0 1246 pgl_epoint_set_latlon(point, PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1));
jbe@0 1247 PG_RETURN_POINTER(point);
jbe@0 1248 }
jbe@0 1249
jbe@0 1250 /* parse point ("epoint" in SQL) */
jbe@0 1251 /* format: '[NS]<float> [EW]<float>' */
jbe@0 1252 PG_FUNCTION_INFO_V1(pgl_epoint_in);
jbe@0 1253 Datum pgl_epoint_in(PG_FUNCTION_ARGS) {
jbe@0 1254 char *str = PG_GETARG_CSTRING(0); /* input string */
jbe@0 1255 char *strptr = str; /* current position within string */
jbe@0 1256 int done = 0; /* bit mask storing if latitude or longitude was read */
jbe@0 1257 double lat, lon; /* parsed values as double precision floats */
jbe@0 1258 pgl_point *point; /* return value (to be palloc'ed) */
jbe@0 1259 /* parse two floats (each latitude or longitude) separated by white-space */
jbe@0 1260 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1261 if (strptr != str && isspace(strptr[-1])) {
jbe@0 1262 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1263 }
jbe@0 1264 /* require end of string, and latitude and longitude parsed successfully */
jbe@0 1265 if (strptr[0] || done != PGL_SCAN_LATLON) {
jbe@0 1266 ereport(ERROR, (
jbe@0 1267 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1268 errmsg("invalid input syntax for type epoint: \"%s\"", str)
jbe@0 1269 ));
jbe@0 1270 }
jbe@0 1271 /* allocate memory for result */
jbe@0 1272 point = (pgl_point *)palloc(sizeof(pgl_point));
jbe@0 1273 /* set latitude and longitude (and perform checks) */
jbe@0 1274 pgl_epoint_set_latlon(point, lat, lon);
jbe@0 1275 /* return result */
jbe@0 1276 PG_RETURN_POINTER(point);
jbe@0 1277 }
jbe@0 1278
jbe@0 1279 /* create box ("ebox" in SQL) that is empty */
jbe@0 1280 PG_FUNCTION_INFO_V1(pgl_create_empty_ebox);
jbe@0 1281 Datum pgl_create_empty_ebox(PG_FUNCTION_ARGS) {
jbe@0 1282 pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1283 pgl_box_set_empty(box);
jbe@0 1284 PG_RETURN_POINTER(box);
jbe@0 1285 }
jbe@0 1286
jbe@0 1287 /* set box to given boundaries (including checks) */
jbe@0 1288 static void pgl_ebox_set_boundaries(
jbe@0 1289 pgl_box *box,
jbe@0 1290 double lat_min, double lat_max, double lon_min, double lon_max
jbe@0 1291 ) {
jbe@0 1292 /* if minimum latitude is greater than maximum latitude, return empty box */
jbe@0 1293 if (lat_min > lat_max) {
jbe@0 1294 pgl_box_set_empty(box);
jbe@0 1295 return;
jbe@0 1296 }
jbe@0 1297 /* otherwise reject infinite or NaN values */
jbe@0 1298 if (
jbe@0 1299 !isfinite(lat_min) || !isfinite(lat_max) ||
jbe@0 1300 !isfinite(lon_min) || !isfinite(lon_max)
jbe@0 1301 ) {
jbe@0 1302 ereport(ERROR, (
jbe@0 1303 errcode(ERRCODE_DATA_EXCEPTION),
jbe@0 1304 errmsg("ebox requires finite coordinates")
jbe@0 1305 ));
jbe@0 1306 }
jbe@0 1307 /* check latitude bounds */
jbe@0 1308 if (lat_max < -90) {
jbe@0 1309 ereport(WARNING, (errmsg("northern latitude exceeds south pole")));
jbe@0 1310 lat_max = -90;
jbe@0 1311 } else if (lat_max > 90) {
jbe@0 1312 ereport(WARNING, (errmsg("northern latitude exceeds north pole")));
jbe@0 1313 lat_max = 90;
jbe@0 1314 }
jbe@0 1315 if (lat_min < -90) {
jbe@0 1316 ereport(WARNING, (errmsg("southern latitude exceeds south pole")));
jbe@0 1317 lat_min = -90;
jbe@0 1318 } else if (lat_min > 90) {
jbe@0 1319 ereport(WARNING, (errmsg("southern latitude exceeds north pole")));
jbe@0 1320 lat_min = 90;
jbe@0 1321 }
jbe@0 1322 /* check if all longitudes are included */
jbe@0 1323 if (lon_max - lon_min >= 360) {
jbe@0 1324 if (lon_max - lon_min > 360) ereport(WARNING, (
jbe@0 1325 errmsg("longitude coverage greater than 360 degrees")
jbe@0 1326 ));
jbe@0 1327 lon_min = -180;
jbe@0 1328 lon_max = 180;
jbe@0 1329 } else {
jbe@0 1330 /* normalize longitude bounds */
jbe@0 1331 if (lon_min < -180) lon_min += 360 - trunc(lon_min / 360) * 360;
jbe@0 1332 else if (lon_min > 180) lon_min -= 360 + trunc(lon_min / 360) * 360;
jbe@0 1333 if (lon_max < -180) lon_max += 360 - trunc(lon_max / 360) * 360;
jbe@0 1334 else if (lon_max > 180) lon_max -= 360 + trunc(lon_max / 360) * 360;
jbe@0 1335 }
jbe@0 1336 /* store rounded latitude/longitude values for round-trip safety */
jbe@0 1337 box->lat_min = pgl_round(lat_min);
jbe@0 1338 box->lat_max = pgl_round(lat_max);
jbe@0 1339 box->lon_min = pgl_round(lon_min);
jbe@0 1340 box->lon_max = pgl_round(lon_max);
jbe@0 1341 /* ensure that rounding does not change orientation */
jbe@0 1342 if (lon_min > lon_max && box->lon_min == box->lon_max) {
jbe@0 1343 box->lon_min = -180;
jbe@0 1344 box->lon_max = 180;
jbe@0 1345 }
jbe@0 1346 }
jbe@0 1347
jbe@0 1348 /* create box ("ebox" in SQL) from min/max latitude and min/max longitude */
jbe@0 1349 PG_FUNCTION_INFO_V1(pgl_create_ebox);
jbe@0 1350 Datum pgl_create_ebox(PG_FUNCTION_ARGS) {
jbe@0 1351 pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1352 pgl_ebox_set_boundaries(
jbe@0 1353 box,
jbe@0 1354 PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1),
jbe@0 1355 PG_GETARG_FLOAT8(2), PG_GETARG_FLOAT8(3)
jbe@0 1356 );
jbe@0 1357 PG_RETURN_POINTER(box);
jbe@0 1358 }
jbe@0 1359
jbe@0 1360 /* create box ("ebox" in SQL) from two points ("epoint"s) */
jbe@0 1361 /* (can not be used to cover a longitude range of more than 120 degrees) */
jbe@0 1362 PG_FUNCTION_INFO_V1(pgl_create_ebox_from_epoints);
jbe@0 1363 Datum pgl_create_ebox_from_epoints(PG_FUNCTION_ARGS) {
jbe@0 1364 pgl_point *point1 = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1365 pgl_point *point2 = (pgl_point *)PG_GETARG_POINTER(1);
jbe@0 1366 pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1367 double lat_min, lat_max, lon_min, lon_max;
jbe@0 1368 double dlon; /* longitude range (delta longitude) */
jbe@0 1369 /* order latitude and longitude boundaries */
jbe@0 1370 if (point2->lat < point1->lat) {
jbe@0 1371 lat_min = point2->lat;
jbe@0 1372 lat_max = point1->lat;
jbe@0 1373 } else {
jbe@0 1374 lat_min = point1->lat;
jbe@0 1375 lat_max = point2->lat;
jbe@0 1376 }
jbe@0 1377 if (point2->lon < point1->lon) {
jbe@0 1378 lon_min = point2->lon;
jbe@0 1379 lon_max = point1->lon;
jbe@0 1380 } else {
jbe@0 1381 lon_min = point1->lon;
jbe@0 1382 lon_max = point2->lon;
jbe@0 1383 }
jbe@0 1384 /* calculate longitude range (round to avoid floating point errors) */
jbe@0 1385 dlon = pgl_round(lon_max - lon_min);
jbe@0 1386 /* determine east-west direction */
jbe@0 1387 if (dlon >= 240) {
jbe@0 1388 /* assume that 180th meridian is crossed and swap min/max longitude */
jbe@0 1389 double swap = lon_min; lon_min = lon_max; lon_max = swap;
jbe@0 1390 } else if (dlon > 120) {
jbe@0 1391 /* unclear orientation since delta longitude > 120 */
jbe@0 1392 ereport(ERROR, (
jbe@0 1393 errcode(ERRCODE_DATA_EXCEPTION),
jbe@0 1394 errmsg("can not determine east/west orientation for ebox")
jbe@0 1395 ));
jbe@0 1396 }
jbe@0 1397 /* use boundaries to setup box (and perform checks) */
jbe@0 1398 pgl_ebox_set_boundaries(box, lat_min, lat_max, lon_min, lon_max);
jbe@0 1399 /* return result */
jbe@0 1400 PG_RETURN_POINTER(box);
jbe@0 1401 }
jbe@0 1402
jbe@0 1403 /* parse box ("ebox" in SQL) */
jbe@0 1404 /* format: '[NS]<float> [EW]<float> [NS]<float> [EW]<float>'
jbe@0 1405 or: '[NS]<float> [NS]<float> [EW]<float> [EW]<float>' */
jbe@0 1406 PG_FUNCTION_INFO_V1(pgl_ebox_in);
jbe@0 1407 Datum pgl_ebox_in(PG_FUNCTION_ARGS) {
jbe@0 1408 char *str = PG_GETARG_CSTRING(0); /* input string */
jbe@0 1409 char *str_lower; /* lower case version of input string */
jbe@0 1410 char *strptr; /* current position within string */
jbe@0 1411 int valid; /* number of valid chars */
jbe@0 1412 int done; /* specifies if latitude or longitude was read */
jbe@0 1413 double val; /* temporary variable */
jbe@0 1414 int lat_count = 0; /* count of latitude values parsed */
jbe@0 1415 int lon_count = 0; /* count of longitufde values parsed */
jbe@0 1416 double lat_min, lat_max, lon_min, lon_max; /* see pgl_box struct */
jbe@0 1417 pgl_box *box; /* return value (to be palloc'ed) */
jbe@0 1418 /* lowercase input */
jbe@0 1419 str_lower = psprintf("%s", str);
jbe@0 1420 for (strptr=str_lower; *strptr; strptr++) {
jbe@0 1421 if (*strptr >= 'A' && *strptr <= 'Z') *strptr += 'a' - 'A';
jbe@0 1422 }
jbe@0 1423 /* reset reading position to start of (lowercase) string */
jbe@0 1424 strptr = str_lower;
jbe@0 1425 /* check if empty box */
jbe@0 1426 valid = 0;
jbe@0 1427 sscanf(strptr, " empty %n", &valid);
jbe@0 1428 if (valid && strptr[valid] == 0) {
jbe@0 1429 /* allocate and return empty box */
jbe@0 1430 box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1431 pgl_box_set_empty(box);
jbe@0 1432 PG_RETURN_POINTER(box);
jbe@0 1433 }
jbe@0 1434 /* demand four blocks separated by whitespace */
jbe@0 1435 valid = 0;
jbe@0 1436 sscanf(strptr, " %*s %*s %*s %*s %n", &valid);
jbe@0 1437 /* if four blocks separated by whitespace exist, parse those blocks */
jbe@0 1438 if (strptr[valid] == 0) while (strptr[0]) {
jbe@0 1439 /* parse either latitude or longitude (whichever found in input string) */
jbe@0 1440 done = pgl_scan(&strptr, &val, &val);
jbe@0 1441 /* store latitude or longitude in lat_min, lat_max, lon_min, or lon_max */
jbe@0 1442 if (done == PGL_SCAN_LAT) {
jbe@0 1443 if (!lat_count) lat_min = val; else lat_max = val;
jbe@0 1444 lat_count++;
jbe@0 1445 } else if (done == PGL_SCAN_LON) {
jbe@0 1446 if (!lon_count) lon_min = val; else lon_max = val;
jbe@0 1447 lon_count++;
jbe@0 1448 } else {
jbe@0 1449 break;
jbe@0 1450 }
jbe@0 1451 }
jbe@0 1452 /* require end of string, and two latitude and two longitude values */
jbe@0 1453 if (strptr[0] || lat_count != 2 || lon_count != 2) {
jbe@0 1454 ereport(ERROR, (
jbe@0 1455 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1456 errmsg("invalid input syntax for type ebox: \"%s\"", str)
jbe@0 1457 ));
jbe@0 1458 }
jbe@0 1459 /* free lower case string */
jbe@0 1460 pfree(str_lower);
jbe@0 1461 /* order boundaries (maximum greater than minimum) */
jbe@0 1462 if (lat_min > lat_max) { val = lat_min; lat_min = lat_max; lat_max = val; }
jbe@0 1463 if (lon_min > lon_max) { val = lon_min; lon_min = lon_max; lon_max = val; }
jbe@0 1464 /* allocate memory for result */
jbe@0 1465 box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1466 /* set boundaries (and perform checks) */
jbe@0 1467 pgl_ebox_set_boundaries(box, lat_min, lat_max, lon_min, lon_max);
jbe@0 1468 /* return result */
jbe@0 1469 PG_RETURN_POINTER(box);
jbe@0 1470 }
jbe@0 1471
jbe@0 1472 /* set circle to given latitude, longitude, and radius (including checks) */
jbe@0 1473 static void pgl_ecircle_set_latlon_radius(
jbe@0 1474 pgl_circle *circle, double lat, double lon, double radius
jbe@0 1475 ) {
jbe@0 1476 /* set center point (including checks) */
jbe@0 1477 pgl_epoint_set_latlon(&(circle->center), lat, lon);
jbe@0 1478 /* handle non-positive radius */
jbe@0 1479 if (isnan(radius)) {
jbe@0 1480 ereport(ERROR, (
jbe@0 1481 errcode(ERRCODE_DATA_EXCEPTION),
jbe@0 1482 errmsg("invalid radius for ecircle")
jbe@0 1483 ));
jbe@0 1484 }
jbe@0 1485 if (radius == 0) radius = 0; /* avoids -0 */
jbe@0 1486 else if (radius < 0) {
jbe@0 1487 if (isfinite(radius)) {
jbe@0 1488 ereport(NOTICE, (errmsg("negative radius converted to minus infinity")));
jbe@0 1489 }
jbe@0 1490 radius = -INFINITY;
jbe@0 1491 }
jbe@0 1492 /* store radius (round-trip safety is ensured by pgl_print_float) */
jbe@0 1493 circle->radius = radius;
jbe@0 1494 }
jbe@0 1495
jbe@0 1496 /* create circle ("ecircle" in SQL) from latitude, longitude, and radius */
jbe@0 1497 PG_FUNCTION_INFO_V1(pgl_create_ecircle);
jbe@0 1498 Datum pgl_create_ecircle(PG_FUNCTION_ARGS) {
jbe@0 1499 pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle));
jbe@0 1500 pgl_ecircle_set_latlon_radius(
jbe@0 1501 circle, PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1), PG_GETARG_FLOAT8(2)
jbe@0 1502 );
jbe@0 1503 PG_RETURN_POINTER(circle);
jbe@0 1504 }
jbe@0 1505
jbe@0 1506 /* create circle ("ecircle" in SQL) from point ("epoint"), and radius */
jbe@0 1507 PG_FUNCTION_INFO_V1(pgl_create_ecircle_from_epoint);
jbe@0 1508 Datum pgl_create_ecircle_from_epoint(PG_FUNCTION_ARGS) {
jbe@0 1509 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1510 double radius = PG_GETARG_FLOAT8(1);
jbe@0 1511 pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle));
jbe@0 1512 /* set latitude, longitude, radius (and perform checks) */
jbe@0 1513 pgl_ecircle_set_latlon_radius(circle, point->lat, point->lon, radius);
jbe@0 1514 /* return result */
jbe@0 1515 PG_RETURN_POINTER(circle);
jbe@0 1516 }
jbe@0 1517
jbe@0 1518 /* parse circle ("ecircle" in SQL) */
jbe@0 1519 /* format: '[NS]<float> [EW]<float> <float>' */
jbe@0 1520 PG_FUNCTION_INFO_V1(pgl_ecircle_in);
jbe@0 1521 Datum pgl_ecircle_in(PG_FUNCTION_ARGS) {
jbe@0 1522 char *str = PG_GETARG_CSTRING(0); /* input string */
jbe@0 1523 char *strptr = str; /* current position within string */
jbe@0 1524 double lat, lon, radius; /* parsed values as double precision flaots */
jbe@0 1525 int valid = 0; /* number of valid chars */
jbe@0 1526 int done = 0; /* stores if latitude and/or longitude was read */
jbe@0 1527 pgl_circle *circle; /* return value (to be palloc'ed) */
jbe@0 1528 /* demand three blocks separated by whitespace */
jbe@0 1529 sscanf(strptr, " %*s %*s %*s %n", &valid);
jbe@0 1530 /* if three blocks separated by whitespace exist, parse those blocks */
jbe@0 1531 if (strptr[valid] == 0) {
jbe@0 1532 /* parse latitude and longitude */
jbe@0 1533 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1534 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1535 /* parse radius (while incrementing strptr by number of bytes parsed) */
jbe@0 1536 valid = 0;
jbe@0 1537 if (sscanf(strptr, " %lf %n", &radius, &valid) == 1) strptr += valid;
jbe@0 1538 }
jbe@0 1539 /* require end of string and both latitude and longitude being parsed */
jbe@0 1540 if (strptr[0] || done != PGL_SCAN_LATLON) {
jbe@0 1541 ereport(ERROR, (
jbe@0 1542 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1543 errmsg("invalid input syntax for type ecircle: \"%s\"", str)
jbe@0 1544 ));
jbe@0 1545 }
jbe@0 1546 /* allocate memory for result */
jbe@0 1547 circle = (pgl_circle *)palloc(sizeof(pgl_circle));
jbe@0 1548 /* set latitude, longitude, radius (and perform checks) */
jbe@0 1549 pgl_ecircle_set_latlon_radius(circle, lat, lon, radius);
jbe@0 1550 /* return result */
jbe@0 1551 PG_RETURN_POINTER(circle);
jbe@0 1552 }
jbe@0 1553
jbe@0 1554 /* parse cluster ("ecluster" in SQL) */
jbe@0 1555 PG_FUNCTION_INFO_V1(pgl_ecluster_in);
jbe@0 1556 Datum pgl_ecluster_in(PG_FUNCTION_ARGS) {
jbe@0 1557 int i;
jbe@0 1558 char *str = PG_GETARG_CSTRING(0); /* input string */
jbe@0 1559 char *str_lower; /* lower case version of input string */
jbe@0 1560 char *strptr; /* pointer to current reading position of input */
jbe@0 1561 int npoints_total = 0; /* total number of points in cluster */
jbe@0 1562 int nentries = 0; /* total number of entries */
jbe@0 1563 pgl_newentry *entries; /* array of pgl_newentry to create pgl_cluster */
jbe@0 1564 int entries_buflen = 4; /* maximum number of elements in entries array */
jbe@0 1565 int valid; /* number of valid chars processed */
jbe@0 1566 double lat, lon; /* latitude and longitude of parsed point */
jbe@0 1567 int entrytype; /* current entry type */
jbe@0 1568 int npoints; /* number of points in current entry */
jbe@0 1569 pgl_point *points; /* array of pgl_point for pgl_newentry */
jbe@0 1570 int points_buflen; /* maximum number of elements in points array */
jbe@0 1571 int done; /* return value of pgl_scan function */
jbe@0 1572 pgl_cluster *cluster; /* created cluster */
jbe@0 1573 /* lowercase input */
jbe@0 1574 str_lower = psprintf("%s", str);
jbe@0 1575 for (strptr=str_lower; *strptr; strptr++) {
jbe@0 1576 if (*strptr >= 'A' && *strptr <= 'Z') *strptr += 'a' - 'A';
jbe@0 1577 }
jbe@0 1578 /* reset reading position to start of (lowercase) string */
jbe@0 1579 strptr = str_lower;
jbe@0 1580 /* allocate initial buffer for entries */
jbe@0 1581 entries = palloc(entries_buflen * sizeof(pgl_newentry));
jbe@0 1582 /* parse until end of string */
jbe@0 1583 while (strptr[0]) {
jbe@0 1584 /* require previous white-space or closing parenthesis before next token */
jbe@0 1585 if (strptr != str_lower && !isspace(strptr[-1]) && strptr[-1] != ')') {
jbe@0 1586 goto pgl_ecluster_in_error;
jbe@0 1587 }
jbe@0 1588 /* ignore token "empty" */
jbe@0 1589 valid = 0; sscanf(strptr, " empty %n", &valid);
jbe@0 1590 if (valid) { strptr += valid; continue; }
jbe@0 1591 /* test for "point" token */
jbe@0 1592 valid = 0; sscanf(strptr, " point ( %n", &valid);
jbe@0 1593 if (valid) {
jbe@0 1594 strptr += valid;
jbe@0 1595 entrytype = PGL_ENTRY_POINT;
jbe@0 1596 goto pgl_ecluster_in_type_ok;
jbe@0 1597 }
jbe@0 1598 /* test for "path" token */
jbe@0 1599 valid = 0; sscanf(strptr, " path ( %n", &valid);
jbe@0 1600 if (valid) {
jbe@0 1601 strptr += valid;
jbe@0 1602 entrytype = PGL_ENTRY_PATH;
jbe@0 1603 goto pgl_ecluster_in_type_ok;
jbe@0 1604 }
jbe@0 1605 /* test for "outline" token */
jbe@0 1606 valid = 0; sscanf(strptr, " outline ( %n", &valid);
jbe@0 1607 if (valid) {
jbe@0 1608 strptr += valid;
jbe@0 1609 entrytype = PGL_ENTRY_OUTLINE;
jbe@0 1610 goto pgl_ecluster_in_type_ok;
jbe@0 1611 }
jbe@0 1612 /* test for "polygon" token */
jbe@0 1613 valid = 0; sscanf(strptr, " polygon ( %n", &valid);
jbe@0 1614 if (valid) {
jbe@0 1615 strptr += valid;
jbe@0 1616 entrytype = PGL_ENTRY_POLYGON;
jbe@0 1617 goto pgl_ecluster_in_type_ok;
jbe@0 1618 }
jbe@0 1619 /* error if no valid token found */
jbe@0 1620 goto pgl_ecluster_in_error;
jbe@0 1621 pgl_ecluster_in_type_ok:
jbe@0 1622 /* check if pgl_newentry array needs to grow */
jbe@0 1623 if (nentries == entries_buflen) {
jbe@0 1624 pgl_newentry *newbuf;
jbe@0 1625 entries_buflen *= 2;
jbe@0 1626 newbuf = palloc(entries_buflen * sizeof(pgl_newentry));
jbe@0 1627 memcpy(newbuf, entries, nentries * sizeof(pgl_newentry));
jbe@0 1628 pfree(entries);
jbe@0 1629 entries = newbuf;
jbe@0 1630 }
jbe@0 1631 /* reset number of points for current entry */
jbe@0 1632 npoints = 0;
jbe@0 1633 /* allocate array for points */
jbe@0 1634 points_buflen = 4;
jbe@0 1635 points = palloc(points_buflen * sizeof(pgl_point));
jbe@0 1636 /* parse until closing parenthesis */
jbe@0 1637 while (strptr[0] != ')') {
jbe@0 1638 /* error on unexpected end of string */
jbe@0 1639 if (strptr[0] == 0) goto pgl_ecluster_in_error;
jbe@0 1640 /* mark neither latitude nor longitude as read */
jbe@0 1641 done = PGL_SCAN_NONE;
jbe@0 1642 /* require white-space before second, third, etc. point */
jbe@0 1643 if (npoints != 0 && !isspace(strptr[-1])) goto pgl_ecluster_in_error;
jbe@0 1644 /* scan latitude (or longitude) */
jbe@0 1645 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1646 /* require white-space before second coordinate */
jbe@0 1647 if (strptr != str && !isspace(strptr[-1])) goto pgl_ecluster_in_error;
jbe@0 1648 /* scan longitude (or latitude) */
jbe@0 1649 done |= pgl_scan(&strptr, &lat, &lon);
jbe@0 1650 /* error unless both latitude and longitude were parsed */
jbe@0 1651 if (done != PGL_SCAN_LATLON) goto pgl_ecluster_in_error;
jbe@0 1652 /* throw error if number of points is too high */
jbe@0 1653 if (npoints_total == PGL_CLUSTER_MAXPOINTS) {
jbe@0 1654 ereport(ERROR, (
jbe@0 1655 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1656 errmsg(
jbe@0 1657 "too many points for ecluster entry (maximum %i)",
jbe@0 1658 PGL_CLUSTER_MAXPOINTS
jbe@0 1659 )
jbe@0 1660 ));
jbe@0 1661 }
jbe@0 1662 /* check if pgl_point array needs to grow */
jbe@0 1663 if (npoints == points_buflen) {
jbe@0 1664 pgl_point *newbuf;
jbe@0 1665 points_buflen *= 2;
jbe@0 1666 newbuf = palloc(points_buflen * sizeof(pgl_point));
jbe@0 1667 memcpy(newbuf, points, npoints * sizeof(pgl_point));
jbe@0 1668 pfree(points);
jbe@0 1669 points = newbuf;
jbe@0 1670 }
jbe@0 1671 /* append point to pgl_point array (includes checks) */
jbe@0 1672 pgl_epoint_set_latlon(&(points[npoints++]), lat, lon);
jbe@0 1673 /* increase total number of points */
jbe@0 1674 npoints_total++;
jbe@0 1675 }
jbe@0 1676 /* error if entry has no points */
jbe@0 1677 if (!npoints) goto pgl_ecluster_in_error;
jbe@0 1678 /* entries with one point are automatically of type "point" */
jbe@0 1679 if (npoints == 1) entrytype = PGL_ENTRY_POINT;
jbe@0 1680 /* if entries have more than one point */
jbe@0 1681 else {
jbe@0 1682 /* throw error if entry type is "point" */
jbe@0 1683 if (entrytype == PGL_ENTRY_POINT) {
jbe@0 1684 ereport(ERROR, (
jbe@0 1685 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1686 errmsg("invalid input syntax for type ecluster (point entry with more than one point)")
jbe@0 1687 ));
jbe@0 1688 }
jbe@0 1689 /* coerce outlines and polygons with more than 2 points to be a path */
jbe@0 1690 if (npoints == 2) entrytype = PGL_ENTRY_PATH;
jbe@0 1691 }
jbe@0 1692 /* append entry to pgl_newentry array */
jbe@0 1693 entries[nentries].entrytype = entrytype;
jbe@0 1694 entries[nentries].npoints = npoints;
jbe@0 1695 entries[nentries].points = points;
jbe@0 1696 nentries++;
jbe@0 1697 /* consume closing parenthesis */
jbe@0 1698 strptr++;
jbe@0 1699 /* consume white-space */
jbe@0 1700 while (isspace(strptr[0])) strptr++;
jbe@0 1701 }
jbe@0 1702 /* free lower case string */
jbe@0 1703 pfree(str_lower);
jbe@0 1704 /* create cluster from pgl_newentry array */
jbe@0 1705 cluster = pgl_new_cluster(nentries, entries);
jbe@0 1706 /* free pgl_newentry array */
jbe@0 1707 for (i=0; i<nentries; i++) pfree(entries[i].points);
jbe@0 1708 pfree(entries);
jbe@0 1709 /* set bounding circle of cluster and check east/west orientation */
jbe@0 1710 if (!pgl_finalize_cluster(cluster)) {
jbe@0 1711 ereport(ERROR, (
jbe@0 1712 errcode(ERRCODE_DATA_EXCEPTION),
jbe@0 1713 errmsg("can not determine east/west orientation for ecluster"),
jbe@0 1714 errhint("Ensure that each entry has a longitude span of less than 180 degrees.")
jbe@0 1715 ));
jbe@0 1716 }
jbe@0 1717 /* return cluster */
jbe@0 1718 PG_RETURN_POINTER(cluster);
jbe@0 1719 /* code to throw error */
jbe@0 1720 pgl_ecluster_in_error:
jbe@0 1721 ereport(ERROR, (
jbe@0 1722 errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
jbe@0 1723 errmsg("invalid input syntax for type ecluster: \"%s\"", str)
jbe@0 1724 ));
jbe@0 1725 }
jbe@0 1726
jbe@0 1727 /* convert point ("epoint") to string representation */
jbe@0 1728 PG_FUNCTION_INFO_V1(pgl_epoint_out);
jbe@0 1729 Datum pgl_epoint_out(PG_FUNCTION_ARGS) {
jbe@0 1730 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1731 char latstr[PGL_NUMBUFLEN];
jbe@0 1732 char lonstr[PGL_NUMBUFLEN];
jbe@0 1733 pgl_print_lat(latstr, point->lat);
jbe@0 1734 pgl_print_lon(lonstr, point->lon);
jbe@0 1735 PG_RETURN_CSTRING(psprintf("%s %s", latstr, lonstr));
jbe@0 1736 }
jbe@0 1737
jbe@0 1738 /* convert box ("ebox") to string representation */
jbe@0 1739 PG_FUNCTION_INFO_V1(pgl_ebox_out);
jbe@0 1740 Datum pgl_ebox_out(PG_FUNCTION_ARGS) {
jbe@0 1741 pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0);
jbe@0 1742 double lon_min = box->lon_min;
jbe@0 1743 double lon_max = box->lon_max;
jbe@0 1744 char lat_min_str[PGL_NUMBUFLEN];
jbe@0 1745 char lat_max_str[PGL_NUMBUFLEN];
jbe@0 1746 char lon_min_str[PGL_NUMBUFLEN];
jbe@0 1747 char lon_max_str[PGL_NUMBUFLEN];
jbe@0 1748 /* return string "empty" if box is set to be empty */
jbe@0 1749 if (box->lat_min > box->lat_max) PG_RETURN_CSTRING("empty");
jbe@0 1750 /* use boundaries exceeding W180 or E180 if 180th meridian is enclosed */
jbe@0 1751 /* (required since pgl_box_in orders the longitude boundaries) */
jbe@0 1752 if (lon_min > lon_max) {
jbe@0 1753 if (lon_min + lon_max >= 0) lon_min -= 360;
jbe@0 1754 else lon_max += 360;
jbe@0 1755 }
jbe@0 1756 /* format and return result */
jbe@0 1757 pgl_print_lat(lat_min_str, box->lat_min);
jbe@0 1758 pgl_print_lat(lat_max_str, box->lat_max);
jbe@0 1759 pgl_print_lon(lon_min_str, lon_min);
jbe@0 1760 pgl_print_lon(lon_max_str, lon_max);
jbe@0 1761 PG_RETURN_CSTRING(psprintf(
jbe@0 1762 "%s %s %s %s",
jbe@0 1763 lat_min_str, lon_min_str, lat_max_str, lon_max_str
jbe@0 1764 ));
jbe@0 1765 }
jbe@0 1766
jbe@0 1767 /* convert circle ("ecircle") to string representation */
jbe@0 1768 PG_FUNCTION_INFO_V1(pgl_ecircle_out);
jbe@0 1769 Datum pgl_ecircle_out(PG_FUNCTION_ARGS) {
jbe@0 1770 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 1771 char latstr[PGL_NUMBUFLEN];
jbe@0 1772 char lonstr[PGL_NUMBUFLEN];
jbe@0 1773 char radstr[PGL_NUMBUFLEN];
jbe@0 1774 pgl_print_lat(latstr, circle->center.lat);
jbe@0 1775 pgl_print_lon(lonstr, circle->center.lon);
jbe@0 1776 pgl_print_float(radstr, circle->radius);
jbe@0 1777 PG_RETURN_CSTRING(psprintf("%s %s %s", latstr, lonstr, radstr));
jbe@0 1778 }
jbe@0 1779
jbe@0 1780 /* convert cluster ("ecluster") to string representation */
jbe@0 1781 PG_FUNCTION_INFO_V1(pgl_ecluster_out);
jbe@0 1782 Datum pgl_ecluster_out(PG_FUNCTION_ARGS) {
jbe@0 1783 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
jbe@0 1784 char latstr[PGL_NUMBUFLEN]; /* string buffer for latitude */
jbe@0 1785 char lonstr[PGL_NUMBUFLEN]; /* string buffer for longitude */
jbe@0 1786 char ***strings; /* array of array of strings */
jbe@0 1787 char *string; /* string of current token */
jbe@0 1788 char *res, *resptr; /* result and pointer to current write position */
jbe@0 1789 size_t reslen = 1; /* length of result (init with 1 for terminator) */
jbe@0 1790 int npoints; /* number of points of current entry */
jbe@0 1791 int i, j; /* i: entry, j: point in entry */
jbe@0 1792 /* handle empty clusters */
jbe@0 1793 if (cluster->nentries == 0) {
jbe@0 1794 /* free detoasted cluster (if copy) */
jbe@0 1795 PG_FREE_IF_COPY(cluster, 0);
jbe@0 1796 /* return static result */
jbe@0 1797 PG_RETURN_CSTRING("empty");
jbe@0 1798 }
jbe@0 1799 /* allocate array of array of strings */
jbe@0 1800 strings = palloc(cluster->nentries * sizeof(char **));
jbe@0 1801 /* iterate over all entries in cluster */
jbe@0 1802 for (i=0; i<cluster->nentries; i++) {
jbe@0 1803 /* get number of points in entry */
jbe@0 1804 npoints = cluster->entries[i].npoints;
jbe@0 1805 /* allocate array of strings (one string for each point plus two extra) */
jbe@0 1806 strings[i] = palloc((2 + npoints) * sizeof(char *));
jbe@0 1807 /* determine opening string */
jbe@0 1808 switch (cluster->entries[i].entrytype) {
jbe@0 1809 case PGL_ENTRY_POINT: string = (i==0)?"point (" :" point ("; break;
jbe@0 1810 case PGL_ENTRY_PATH: string = (i==0)?"path (" :" path ("; break;
jbe@0 1811 case PGL_ENTRY_OUTLINE: string = (i==0)?"outline (":" outline ("; break;
jbe@0 1812 case PGL_ENTRY_POLYGON: string = (i==0)?"polygon (":" polygon ("; break;
jbe@0 1813 default: string = (i==0)?"unknown" :" unknown";
jbe@0 1814 }
jbe@0 1815 /* use opening string as first string in array */
jbe@0 1816 strings[i][0] = string;
jbe@0 1817 /* update result length (for allocating result string later) */
jbe@0 1818 reslen += strlen(string);
jbe@0 1819 /* iterate over all points */
jbe@0 1820 for (j=0; j<npoints; j++) {
jbe@0 1821 /* create string representation of point */
jbe@0 1822 pgl_print_lat(latstr, PGL_ENTRY_POINTS(cluster, i)[j].lat);
jbe@0 1823 pgl_print_lon(lonstr, PGL_ENTRY_POINTS(cluster, i)[j].lon);
jbe@0 1824 string = psprintf((j == 0) ? "%s %s" : " %s %s", latstr, lonstr);
jbe@0 1825 /* copy string pointer to string array */
jbe@0 1826 strings[i][j+1] = string;
jbe@0 1827 /* update result length (for allocating result string later) */
jbe@0 1828 reslen += strlen(string);
jbe@0 1829 }
jbe@0 1830 /* use closing parenthesis as last string in array */
jbe@0 1831 strings[i][npoints+1] = ")";
jbe@0 1832 /* update result length (for allocating result string later) */
jbe@0 1833 reslen++;
jbe@0 1834 }
jbe@0 1835 /* allocate result string */
jbe@0 1836 res = palloc(reslen);
jbe@0 1837 /* set write pointer to begin of result string */
jbe@0 1838 resptr = res;
jbe@0 1839 /* copy strings into result string */
jbe@0 1840 for (i=0; i<cluster->nentries; i++) {
jbe@0 1841 npoints = cluster->entries[i].npoints;
jbe@0 1842 for (j=0; j<npoints+2; j++) {
jbe@0 1843 string = strings[i][j];
jbe@0 1844 strcpy(resptr, string);
jbe@0 1845 resptr += strlen(string);
jbe@0 1846 /* free strings allocated by psprintf */
jbe@0 1847 if (j != 0 && j != npoints+1) pfree(string);
jbe@0 1848 }
jbe@0 1849 /* free array of strings */
jbe@0 1850 pfree(strings[i]);
jbe@0 1851 }
jbe@0 1852 /* free array of array of strings */
jbe@0 1853 pfree(strings);
jbe@0 1854 /* free detoasted cluster (if copy) */
jbe@0 1855 PG_FREE_IF_COPY(cluster, 0);
jbe@0 1856 /* return result */
jbe@0 1857 PG_RETURN_CSTRING(res);
jbe@0 1858 }
jbe@0 1859
jbe@0 1860 /* binary input function for point ("epoint") */
jbe@0 1861 PG_FUNCTION_INFO_V1(pgl_epoint_recv);
jbe@0 1862 Datum pgl_epoint_recv(PG_FUNCTION_ARGS) {
jbe@0 1863 StringInfo buf = (StringInfo)PG_GETARG_POINTER(0);
jbe@0 1864 pgl_point *point = (pgl_point *)palloc(sizeof(pgl_point));
jbe@0 1865 point->lat = pq_getmsgfloat8(buf);
jbe@0 1866 point->lon = pq_getmsgfloat8(buf);
jbe@0 1867 PG_RETURN_POINTER(point);
jbe@0 1868 }
jbe@0 1869
jbe@0 1870 /* binary input function for box ("ebox") */
jbe@0 1871 PG_FUNCTION_INFO_V1(pgl_ebox_recv);
jbe@0 1872 Datum pgl_ebox_recv(PG_FUNCTION_ARGS) {
jbe@0 1873 StringInfo buf = (StringInfo)PG_GETARG_POINTER(0);
jbe@0 1874 pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box));
jbe@0 1875 box->lat_min = pq_getmsgfloat8(buf);
jbe@0 1876 box->lat_max = pq_getmsgfloat8(buf);
jbe@0 1877 box->lon_min = pq_getmsgfloat8(buf);
jbe@0 1878 box->lon_max = pq_getmsgfloat8(buf);
jbe@0 1879 PG_RETURN_POINTER(box);
jbe@0 1880 }
jbe@0 1881
jbe@0 1882 /* binary input function for circle ("ecircle") */
jbe@0 1883 PG_FUNCTION_INFO_V1(pgl_ecircle_recv);
jbe@0 1884 Datum pgl_ecircle_recv(PG_FUNCTION_ARGS) {
jbe@0 1885 StringInfo buf = (StringInfo)PG_GETARG_POINTER(0);
jbe@0 1886 pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle));
jbe@0 1887 circle->center.lat = pq_getmsgfloat8(buf);
jbe@0 1888 circle->center.lon = pq_getmsgfloat8(buf);
jbe@0 1889 circle->radius = pq_getmsgfloat8(buf);
jbe@0 1890 PG_RETURN_POINTER(circle);
jbe@0 1891 }
jbe@0 1892
jbe@0 1893 /* TODO: binary receive function for cluster */
jbe@0 1894
jbe@0 1895 /* binary output function for point ("epoint") */
jbe@0 1896 PG_FUNCTION_INFO_V1(pgl_epoint_send);
jbe@0 1897 Datum pgl_epoint_send(PG_FUNCTION_ARGS) {
jbe@0 1898 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1899 StringInfoData buf;
jbe@0 1900 pq_begintypsend(&buf);
jbe@0 1901 pq_sendfloat8(&buf, point->lat);
jbe@0 1902 pq_sendfloat8(&buf, point->lon);
jbe@0 1903 PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
jbe@0 1904 }
jbe@0 1905
jbe@0 1906 /* binary output function for box ("ebox") */
jbe@0 1907 PG_FUNCTION_INFO_V1(pgl_ebox_send);
jbe@0 1908 Datum pgl_ebox_send(PG_FUNCTION_ARGS) {
jbe@0 1909 pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0);
jbe@0 1910 StringInfoData buf;
jbe@0 1911 pq_begintypsend(&buf);
jbe@0 1912 pq_sendfloat8(&buf, box->lat_min);
jbe@0 1913 pq_sendfloat8(&buf, box->lat_max);
jbe@0 1914 pq_sendfloat8(&buf, box->lon_min);
jbe@0 1915 pq_sendfloat8(&buf, box->lon_max);
jbe@0 1916 PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
jbe@0 1917 }
jbe@0 1918
jbe@0 1919 /* binary output function for circle ("ecircle") */
jbe@0 1920 PG_FUNCTION_INFO_V1(pgl_ecircle_send);
jbe@0 1921 Datum pgl_ecircle_send(PG_FUNCTION_ARGS) {
jbe@0 1922 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 1923 StringInfoData buf;
jbe@0 1924 pq_begintypsend(&buf);
jbe@0 1925 pq_sendfloat8(&buf, circle->center.lat);
jbe@0 1926 pq_sendfloat8(&buf, circle->center.lon);
jbe@0 1927 pq_sendfloat8(&buf, circle->radius);
jbe@0 1928 PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
jbe@0 1929 }
jbe@0 1930
jbe@0 1931 /* TODO: binary send functions for cluster */
jbe@0 1932
jbe@0 1933 /* cast point ("epoint") to box ("ebox") */
jbe@0 1934 PG_FUNCTION_INFO_V1(pgl_epoint_to_ebox);
jbe@0 1935 Datum pgl_epoint_to_ebox(PG_FUNCTION_ARGS) {
jbe@0 1936 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1937 pgl_box *box = palloc(sizeof(pgl_box));
jbe@0 1938 box->lat_min = point->lat;
jbe@0 1939 box->lat_max = point->lat;
jbe@0 1940 box->lon_min = point->lon;
jbe@0 1941 box->lon_max = point->lon;
jbe@0 1942 PG_RETURN_POINTER(box);
jbe@0 1943 }
jbe@0 1944
jbe@0 1945 /* cast point ("epoint") to circle ("ecircle") */
jbe@0 1946 PG_FUNCTION_INFO_V1(pgl_epoint_to_ecircle);
jbe@0 1947 Datum pgl_epoint_to_ecircle(PG_FUNCTION_ARGS) {
jbe@0 1948 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1949 pgl_circle *circle = palloc(sizeof(pgl_box));
jbe@0 1950 circle->center = *point;
jbe@0 1951 circle->radius = 0;
jbe@0 1952 PG_RETURN_POINTER(circle);
jbe@0 1953 }
jbe@0 1954
jbe@0 1955 /* cast point ("epoint") to cluster ("ecluster") */
jbe@0 1956 PG_FUNCTION_INFO_V1(pgl_epoint_to_ecluster);
jbe@0 1957 Datum pgl_epoint_to_ecluster(PG_FUNCTION_ARGS) {
jbe@0 1958 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 1959 pgl_newentry entry;
jbe@0 1960 entry.entrytype = PGL_ENTRY_POINT;
jbe@0 1961 entry.npoints = 1;
jbe@0 1962 entry.points = point;
jbe@0 1963 PG_RETURN_POINTER(pgl_new_cluster(1, &entry));
jbe@0 1964 }
jbe@0 1965
jbe@0 1966 /* cast box ("ebox") to cluster ("ecluster") */
jbe@0 1967 #define pgl_ebox_to_ecluster_macro(i, a, b) \
jbe@0 1968 entries[i].entrytype = PGL_ENTRY_POLYGON; \
jbe@0 1969 entries[i].npoints = 4; \
jbe@0 1970 entries[i].points = points[i]; \
jbe@0 1971 points[i][0].lat = box->lat_min; \
jbe@0 1972 points[i][0].lon = (a); \
jbe@0 1973 points[i][1].lat = box->lat_min; \
jbe@0 1974 points[i][1].lon = (b); \
jbe@0 1975 points[i][2].lat = box->lat_max; \
jbe@0 1976 points[i][2].lon = (b); \
jbe@0 1977 points[i][3].lat = box->lat_max; \
jbe@0 1978 points[i][3].lon = (a);
jbe@0 1979 PG_FUNCTION_INFO_V1(pgl_ebox_to_ecluster);
jbe@0 1980 Datum pgl_ebox_to_ecluster(PG_FUNCTION_ARGS) {
jbe@0 1981 pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0);
jbe@0 1982 double lon, dlon;
jbe@0 1983 int nentries;
jbe@0 1984 pgl_newentry entries[3];
jbe@0 1985 pgl_point points[3][4];
jbe@0 1986 if (box->lat_min > box->lat_max) {
jbe@0 1987 nentries = 0;
jbe@0 1988 } else if (box->lon_min > box->lon_max) {
jbe@0 1989 if (box->lon_min < 0) {
jbe@0 1990 lon = pgl_round((box->lon_min + 180) / 2.0);
jbe@0 1991 nentries = 3;
jbe@0 1992 pgl_ebox_to_ecluster_macro(0, box->lon_min, lon);
jbe@0 1993 pgl_ebox_to_ecluster_macro(1, lon, 180);
jbe@0 1994 pgl_ebox_to_ecluster_macro(2, -180, box->lon_max);
jbe@0 1995 } else if (box->lon_max > 0) {
jbe@0 1996 lon = pgl_round((box->lon_max - 180) / 2.0);
jbe@0 1997 nentries = 3;
jbe@0 1998 pgl_ebox_to_ecluster_macro(0, box->lon_min, 180);
jbe@0 1999 pgl_ebox_to_ecluster_macro(1, -180, lon);
jbe@0 2000 pgl_ebox_to_ecluster_macro(2, lon, box->lon_max);
jbe@0 2001 } else {
jbe@0 2002 nentries = 2;
jbe@0 2003 pgl_ebox_to_ecluster_macro(0, box->lon_min, 180);
jbe@0 2004 pgl_ebox_to_ecluster_macro(1, -180, box->lon_max);
jbe@0 2005 }
jbe@0 2006 } else {
jbe@0 2007 dlon = pgl_round(box->lon_max - box->lon_min);
jbe@0 2008 if (dlon < 180) {
jbe@0 2009 nentries = 1;
jbe@0 2010 pgl_ebox_to_ecluster_macro(0, box->lon_min, box->lon_max);
jbe@0 2011 } else {
jbe@0 2012 lon = pgl_round((box->lon_min + box->lon_max) / 2.0);
jbe@0 2013 if (
jbe@0 2014 pgl_round(lon - box->lon_min) < 180 &&
jbe@0 2015 pgl_round(box->lon_max - lon) < 180
jbe@0 2016 ) {
jbe@0 2017 nentries = 2;
jbe@0 2018 pgl_ebox_to_ecluster_macro(0, box->lon_min, lon);
jbe@0 2019 pgl_ebox_to_ecluster_macro(1, lon, box->lon_max);
jbe@0 2020 } else {
jbe@0 2021 nentries = 3;
jbe@0 2022 pgl_ebox_to_ecluster_macro(0, box->lon_min, -60);
jbe@0 2023 pgl_ebox_to_ecluster_macro(1, -60, 60);
jbe@0 2024 pgl_ebox_to_ecluster_macro(2, 60, box->lon_max);
jbe@0 2025 }
jbe@0 2026 }
jbe@0 2027 }
jbe@0 2028 PG_RETURN_POINTER(pgl_new_cluster(nentries, entries));
jbe@0 2029 }
jbe@0 2030
jbe@0 2031 /* extract latitude from point ("epoint") */
jbe@0 2032 PG_FUNCTION_INFO_V1(pgl_epoint_lat);
jbe@0 2033 Datum pgl_epoint_lat(PG_FUNCTION_ARGS) {
jbe@0 2034 PG_RETURN_FLOAT8(((pgl_point *)PG_GETARG_POINTER(0))->lat);
jbe@0 2035 }
jbe@0 2036
jbe@0 2037 /* extract longitude from point ("epoint") */
jbe@0 2038 PG_FUNCTION_INFO_V1(pgl_epoint_lon);
jbe@0 2039 Datum pgl_epoint_lon(PG_FUNCTION_ARGS) {
jbe@0 2040 PG_RETURN_FLOAT8(((pgl_point *)PG_GETARG_POINTER(0))->lon);
jbe@0 2041 }
jbe@0 2042
jbe@0 2043 /* extract minimum latitude from box ("ebox") */
jbe@0 2044 PG_FUNCTION_INFO_V1(pgl_ebox_lat_min);
jbe@0 2045 Datum pgl_ebox_lat_min(PG_FUNCTION_ARGS) {
jbe@0 2046 PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lat_min);
jbe@0 2047 }
jbe@0 2048
jbe@0 2049 /* extract maximum latitude from box ("ebox") */
jbe@0 2050 PG_FUNCTION_INFO_V1(pgl_ebox_lat_max);
jbe@0 2051 Datum pgl_ebox_lat_max(PG_FUNCTION_ARGS) {
jbe@0 2052 PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lat_max);
jbe@0 2053 }
jbe@0 2054
jbe@0 2055 /* extract minimum longitude from box ("ebox") */
jbe@0 2056 PG_FUNCTION_INFO_V1(pgl_ebox_lon_min);
jbe@0 2057 Datum pgl_ebox_lon_min(PG_FUNCTION_ARGS) {
jbe@0 2058 PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lon_min);
jbe@0 2059 }
jbe@0 2060
jbe@0 2061 /* extract maximum longitude from box ("ebox") */
jbe@0 2062 PG_FUNCTION_INFO_V1(pgl_ebox_lon_max);
jbe@0 2063 Datum pgl_ebox_lon_max(PG_FUNCTION_ARGS) {
jbe@0 2064 PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lon_max);
jbe@0 2065 }
jbe@0 2066
jbe@0 2067 /* extract center point from circle ("ecircle") */
jbe@0 2068 PG_FUNCTION_INFO_V1(pgl_ecircle_center);
jbe@0 2069 Datum pgl_ecircle_center(PG_FUNCTION_ARGS) {
jbe@0 2070 PG_RETURN_POINTER(&(((pgl_circle *)PG_GETARG_POINTER(0))->center));
jbe@0 2071 }
jbe@0 2072
jbe@0 2073 /* extract radius from circle ("ecircle") */
jbe@0 2074 PG_FUNCTION_INFO_V1(pgl_ecircle_radius);
jbe@0 2075 Datum pgl_ecircle_radius(PG_FUNCTION_ARGS) {
jbe@0 2076 PG_RETURN_FLOAT8(((pgl_circle *)PG_GETARG_POINTER(0))->radius);
jbe@0 2077 }
jbe@0 2078
jbe@0 2079 /* check if point is inside box (overlap operator "&&") in SQL */
jbe@0 2080 PG_FUNCTION_INFO_V1(pgl_epoint_ebox_overlap);
jbe@0 2081 Datum pgl_epoint_ebox_overlap(PG_FUNCTION_ARGS) {
jbe@0 2082 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2083 pgl_box *box = (pgl_box *)PG_GETARG_POINTER(1);
jbe@0 2084 PG_RETURN_BOOL(pgl_point_in_box(point, box));
jbe@0 2085 }
jbe@0 2086
jbe@0 2087 /* check if point is inside circle (overlap operator "&&") in SQL */
jbe@0 2088 PG_FUNCTION_INFO_V1(pgl_epoint_ecircle_overlap);
jbe@0 2089 Datum pgl_epoint_ecircle_overlap(PG_FUNCTION_ARGS) {
jbe@0 2090 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2091 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2092 PG_RETURN_BOOL(
jbe@0 2093 pgl_distance(
jbe@0 2094 point->lat, point->lon,
jbe@0 2095 circle->center.lat, circle->center.lon
jbe@0 2096 ) <= circle->radius
jbe@0 2097 );
jbe@0 2098 }
jbe@0 2099
jbe@0 2100 /* check if point is inside cluster (overlap operator "&&") in SQL */
jbe@0 2101 PG_FUNCTION_INFO_V1(pgl_epoint_ecluster_overlap);
jbe@0 2102 Datum pgl_epoint_ecluster_overlap(PG_FUNCTION_ARGS) {
jbe@0 2103 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2104 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2105 bool retval = pgl_point_in_cluster(point, cluster);
jbe@0 2106 PG_FREE_IF_COPY(cluster, 1);
jbe@0 2107 PG_RETURN_BOOL(retval);
jbe@0 2108 }
jbe@0 2109
jbe@0 2110 /* check if two boxes overlap (overlap operator "&&") in SQL */
jbe@0 2111 PG_FUNCTION_INFO_V1(pgl_ebox_overlap);
jbe@0 2112 Datum pgl_ebox_overlap(PG_FUNCTION_ARGS) {
jbe@0 2113 pgl_box *box1 = (pgl_box *)PG_GETARG_POINTER(0);
jbe@0 2114 pgl_box *box2 = (pgl_box *)PG_GETARG_POINTER(1);
jbe@0 2115 PG_RETURN_BOOL(pgl_boxes_overlap(box1, box2));
jbe@0 2116 }
jbe@0 2117
jbe@0 2118 /* check if two circles overlap (overlap operator "&&") in SQL */
jbe@0 2119 PG_FUNCTION_INFO_V1(pgl_ecircle_overlap);
jbe@0 2120 Datum pgl_ecircle_overlap(PG_FUNCTION_ARGS) {
jbe@0 2121 pgl_circle *circle1 = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 2122 pgl_circle *circle2 = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2123 PG_RETURN_BOOL(
jbe@0 2124 pgl_distance(
jbe@0 2125 circle1->center.lat, circle1->center.lon,
jbe@0 2126 circle2->center.lat, circle2->center.lon
jbe@0 2127 ) <= circle1->radius + circle2->radius
jbe@0 2128 );
jbe@0 2129 }
jbe@0 2130
jbe@0 2131 /* check if circle and cluster overlap (overlap operator "&&") in SQL */
jbe@0 2132 PG_FUNCTION_INFO_V1(pgl_ecircle_ecluster_overlap);
jbe@0 2133 Datum pgl_ecircle_ecluster_overlap(PG_FUNCTION_ARGS) {
jbe@0 2134 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 2135 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2136 bool retval = (
jbe@0 2137 pgl_point_cluster_distance(&(circle->center), cluster) <= circle->radius
jbe@0 2138 );
jbe@0 2139 PG_FREE_IF_COPY(cluster, 1);
jbe@0 2140 PG_RETURN_BOOL(retval);
jbe@0 2141 }
jbe@0 2142
jbe@0 2143 /* calculate distance between two points ("<->" operator) in SQL */
jbe@0 2144 PG_FUNCTION_INFO_V1(pgl_epoint_distance);
jbe@0 2145 Datum pgl_epoint_distance(PG_FUNCTION_ARGS) {
jbe@0 2146 pgl_point *point1 = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2147 pgl_point *point2 = (pgl_point *)PG_GETARG_POINTER(1);
jbe@0 2148 PG_RETURN_FLOAT8(pgl_distance(
jbe@0 2149 point1->lat, point1->lon, point2->lat, point2->lon
jbe@0 2150 ));
jbe@0 2151 }
jbe@0 2152
jbe@0 2153 /* calculate point to circle distance ("<->" operator) in SQL */
jbe@0 2154 PG_FUNCTION_INFO_V1(pgl_epoint_ecircle_distance);
jbe@0 2155 Datum pgl_epoint_ecircle_distance(PG_FUNCTION_ARGS) {
jbe@0 2156 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2157 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2158 double distance = pgl_distance(
jbe@0 2159 point->lat, point->lon, circle->center.lat, circle->center.lon
jbe@0 2160 ) - circle->radius;
jbe@0 2161 PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance);
jbe@0 2162 }
jbe@0 2163
jbe@0 2164 /* calculate point to cluster distance ("<->" operator) in SQL */
jbe@0 2165 PG_FUNCTION_INFO_V1(pgl_epoint_ecluster_distance);
jbe@0 2166 Datum pgl_epoint_ecluster_distance(PG_FUNCTION_ARGS) {
jbe@0 2167 pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0);
jbe@0 2168 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2169 double distance = pgl_point_cluster_distance(point, cluster);
jbe@0 2170 PG_FREE_IF_COPY(cluster, 1);
jbe@0 2171 PG_RETURN_FLOAT8(distance);
jbe@0 2172 }
jbe@0 2173
jbe@0 2174 /* calculate distance between two circles ("<->" operator) in SQL */
jbe@0 2175 PG_FUNCTION_INFO_V1(pgl_ecircle_distance);
jbe@0 2176 Datum pgl_ecircle_distance(PG_FUNCTION_ARGS) {
jbe@0 2177 pgl_circle *circle1 = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 2178 pgl_circle *circle2 = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2179 double distance = pgl_distance(
jbe@0 2180 circle1->center.lat, circle1->center.lon,
jbe@0 2181 circle2->center.lat, circle2->center.lon
jbe@0 2182 ) - (circle1->radius + circle2->radius);
jbe@0 2183 PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance);
jbe@0 2184 }
jbe@0 2185
jbe@0 2186 /* calculate circle to cluster distance ("<->" operator) in SQL */
jbe@0 2187 PG_FUNCTION_INFO_V1(pgl_ecircle_ecluster_distance);
jbe@0 2188 Datum pgl_ecircle_ecluster_distance(PG_FUNCTION_ARGS) {
jbe@0 2189 pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0);
jbe@0 2190 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2191 double distance = (
jbe@0 2192 pgl_point_cluster_distance(&(circle->center), cluster) - circle->radius
jbe@0 2193 );
jbe@0 2194 PG_FREE_IF_COPY(cluster, 1);
jbe@0 2195 PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance);
jbe@0 2196 }
jbe@0 2197
jbe@0 2198
jbe@0 2199 /*-----------------------------------------------------------*
jbe@0 2200 * B-tree comparison operators and index support functions *
jbe@0 2201 *-----------------------------------------------------------*/
jbe@0 2202
jbe@0 2203 /* macro for a B-tree operator (without detoasting) */
jbe@0 2204 #define PGL_BTREE_OPER(func, type, cmpfunc, oper) \
jbe@0 2205 PG_FUNCTION_INFO_V1(func); \
jbe@0 2206 Datum func(PG_FUNCTION_ARGS) { \
jbe@0 2207 type *a = (type *)PG_GETARG_POINTER(0); \
jbe@0 2208 type *b = (type *)PG_GETARG_POINTER(1); \
jbe@0 2209 PG_RETURN_BOOL(cmpfunc(a, b) oper 0); \
jbe@0 2210 }
jbe@0 2211
jbe@0 2212 /* macro for a B-tree comparison function (without detoasting) */
jbe@0 2213 #define PGL_BTREE_CMP(func, type, cmpfunc) \
jbe@0 2214 PG_FUNCTION_INFO_V1(func); \
jbe@0 2215 Datum func(PG_FUNCTION_ARGS) { \
jbe@0 2216 type *a = (type *)PG_GETARG_POINTER(0); \
jbe@0 2217 type *b = (type *)PG_GETARG_POINTER(1); \
jbe@0 2218 PG_RETURN_INT32(cmpfunc(a, b)); \
jbe@0 2219 }
jbe@0 2220
jbe@0 2221 /* macro for a B-tree operator (with detoasting) */
jbe@0 2222 #define PGL_BTREE_OPER_DETOAST(func, type, cmpfunc, oper) \
jbe@0 2223 PG_FUNCTION_INFO_V1(func); \
jbe@0 2224 Datum func(PG_FUNCTION_ARGS) { \
jbe@0 2225 bool res; \
jbe@0 2226 type *a = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); \
jbe@0 2227 type *b = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); \
jbe@0 2228 res = cmpfunc(a, b) oper 0; \
jbe@0 2229 PG_FREE_IF_COPY(a, 0); \
jbe@0 2230 PG_FREE_IF_COPY(b, 1); \
jbe@0 2231 PG_RETURN_BOOL(res); \
jbe@0 2232 }
jbe@0 2233
jbe@0 2234 /* macro for a B-tree comparison function (with detoasting) */
jbe@0 2235 #define PGL_BTREE_CMP_DETOAST(func, type, cmpfunc) \
jbe@0 2236 PG_FUNCTION_INFO_V1(func); \
jbe@0 2237 Datum func(PG_FUNCTION_ARGS) { \
jbe@0 2238 int32_t res; \
jbe@0 2239 type *a = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); \
jbe@0 2240 type *b = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); \
jbe@0 2241 res = cmpfunc(a, b); \
jbe@0 2242 PG_FREE_IF_COPY(a, 0); \
jbe@0 2243 PG_FREE_IF_COPY(b, 1); \
jbe@0 2244 PG_RETURN_INT32(res); \
jbe@0 2245 }
jbe@0 2246
jbe@0 2247 /* B-tree operators and comparison function for point */
jbe@0 2248 PGL_BTREE_OPER(pgl_btree_epoint_lt, pgl_point, pgl_point_cmp, <)
jbe@0 2249 PGL_BTREE_OPER(pgl_btree_epoint_le, pgl_point, pgl_point_cmp, <=)
jbe@0 2250 PGL_BTREE_OPER(pgl_btree_epoint_eq, pgl_point, pgl_point_cmp, ==)
jbe@0 2251 PGL_BTREE_OPER(pgl_btree_epoint_ne, pgl_point, pgl_point_cmp, !=)
jbe@0 2252 PGL_BTREE_OPER(pgl_btree_epoint_ge, pgl_point, pgl_point_cmp, >=)
jbe@0 2253 PGL_BTREE_OPER(pgl_btree_epoint_gt, pgl_point, pgl_point_cmp, >)
jbe@0 2254 PGL_BTREE_CMP(pgl_btree_epoint_cmp, pgl_point, pgl_point_cmp)
jbe@0 2255
jbe@0 2256 /* B-tree operators and comparison function for box */
jbe@0 2257 PGL_BTREE_OPER(pgl_btree_ebox_lt, pgl_box, pgl_box_cmp, <)
jbe@0 2258 PGL_BTREE_OPER(pgl_btree_ebox_le, pgl_box, pgl_box_cmp, <=)
jbe@0 2259 PGL_BTREE_OPER(pgl_btree_ebox_eq, pgl_box, pgl_box_cmp, ==)
jbe@0 2260 PGL_BTREE_OPER(pgl_btree_ebox_ne, pgl_box, pgl_box_cmp, !=)
jbe@0 2261 PGL_BTREE_OPER(pgl_btree_ebox_ge, pgl_box, pgl_box_cmp, >=)
jbe@0 2262 PGL_BTREE_OPER(pgl_btree_ebox_gt, pgl_box, pgl_box_cmp, >)
jbe@0 2263 PGL_BTREE_CMP(pgl_btree_ebox_cmp, pgl_box, pgl_box_cmp)
jbe@0 2264
jbe@0 2265 /* B-tree operators and comparison function for circle */
jbe@0 2266 PGL_BTREE_OPER(pgl_btree_ecircle_lt, pgl_circle, pgl_circle_cmp, <)
jbe@0 2267 PGL_BTREE_OPER(pgl_btree_ecircle_le, pgl_circle, pgl_circle_cmp, <=)
jbe@0 2268 PGL_BTREE_OPER(pgl_btree_ecircle_eq, pgl_circle, pgl_circle_cmp, ==)
jbe@0 2269 PGL_BTREE_OPER(pgl_btree_ecircle_ne, pgl_circle, pgl_circle_cmp, !=)
jbe@0 2270 PGL_BTREE_OPER(pgl_btree_ecircle_ge, pgl_circle, pgl_circle_cmp, >=)
jbe@0 2271 PGL_BTREE_OPER(pgl_btree_ecircle_gt, pgl_circle, pgl_circle_cmp, >)
jbe@0 2272 PGL_BTREE_CMP(pgl_btree_ecircle_cmp, pgl_circle, pgl_circle_cmp)
jbe@0 2273
jbe@0 2274
jbe@0 2275 /*--------------------------------*
jbe@0 2276 * GiST index support functions *
jbe@0 2277 *--------------------------------*/
jbe@0 2278
jbe@0 2279 /* GiST "consistent" support function */
jbe@0 2280 PG_FUNCTION_INFO_V1(pgl_gist_consistent);
jbe@0 2281 Datum pgl_gist_consistent(PG_FUNCTION_ARGS) {
jbe@0 2282 GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
jbe@0 2283 pgl_keyptr key = (pgl_keyptr)DatumGetPointer(entry->key);
jbe@0 2284 StrategyNumber strategy = (StrategyNumber)PG_GETARG_UINT16(2);
jbe@0 2285 bool *recheck = (bool *)PG_GETARG_POINTER(4);
jbe@0 2286 /* demand recheck because index and query methods are lossy */
jbe@0 2287 *recheck = true;
jbe@0 2288 /* strategy number 11: equality of two points */
jbe@0 2289 if (strategy == 11) {
jbe@0 2290 /* query datum is another point */
jbe@0 2291 pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1);
jbe@0 2292 /* convert other point to key */
jbe@0 2293 pgl_pointkey querykey;
jbe@0 2294 pgl_point_to_key(query, querykey);
jbe@0 2295 /* return true if both keys overlap */
jbe@0 2296 PG_RETURN_BOOL(pgl_keys_overlap(key, querykey));
jbe@0 2297 }
jbe@0 2298 /* strategy number 13: equality of two circles */
jbe@0 2299 if (strategy == 13) {
jbe@0 2300 /* query datum is another circle */
jbe@0 2301 pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2302 /* convert other circle to key */
jbe@0 2303 pgl_areakey querykey;
jbe@0 2304 pgl_circle_to_key(query, querykey);
jbe@0 2305 /* return true if both keys overlap */
jbe@0 2306 PG_RETURN_BOOL(pgl_keys_overlap(key, querykey));
jbe@0 2307 }
jbe@0 2308 /* for all remaining strategies, keys on empty objects produce no match */
jbe@0 2309 /* (check necessary because query radius may be infinite) */
jbe@0 2310 if (PGL_KEY_IS_EMPTY(key)) PG_RETURN_BOOL(false);
jbe@0 2311 /* strategy number 21: overlapping with point */
jbe@0 2312 if (strategy == 21) {
jbe@0 2313 /* query datum is a point */
jbe@0 2314 pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1);
jbe@0 2315 /* return true if estimated distance (allowed to be smaller than real
jbe@0 2316 distance) between index key and point is zero */
jbe@0 2317 PG_RETURN_BOOL(pgl_estimate_key_distance(key, query) == 0);
jbe@0 2318 }
jbe@0 2319 /* strategy number 22: (point) overlapping with box */
jbe@0 2320 if (strategy == 22) {
jbe@0 2321 /* query datum is a box */
jbe@0 2322 pgl_box *query = (pgl_box *)PG_GETARG_POINTER(1);
jbe@0 2323 /* determine bounding box of indexed key */
jbe@0 2324 pgl_box keybox;
jbe@0 2325 pgl_key_to_box(key, &keybox);
jbe@0 2326 /* return true if query box overlaps with bounding box of indexed key */
jbe@0 2327 PG_RETURN_BOOL(pgl_boxes_overlap(query, &keybox));
jbe@0 2328 }
jbe@0 2329 /* strategy number 23: overlapping with circle */
jbe@0 2330 if (strategy == 23) {
jbe@0 2331 /* query datum is a circle */
jbe@0 2332 pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2333 /* return true if estimated distance (allowed to be smaller than real
jbe@0 2334 distance) between index key and circle center is smaller than radius */
jbe@0 2335 PG_RETURN_BOOL(
jbe@0 2336 pgl_estimate_key_distance(key, &(query->center)) <= query->radius
jbe@0 2337 );
jbe@0 2338 }
jbe@0 2339 /* strategy number 24: overlapping with cluster */
jbe@0 2340 if (strategy == 24) {
jbe@0 2341 bool retval; /* return value */
jbe@0 2342 /* query datum is a cluster */
jbe@0 2343 pgl_cluster *query = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2344 /* return true if estimated distance (allowed to be smaller than real
jbe@0 2345 distance) between index key and circle center is smaller than radius */
jbe@0 2346 retval = (
jbe@0 2347 pgl_estimate_key_distance(key, &(query->bounding.center)) <=
jbe@0 2348 query->bounding.radius
jbe@0 2349 );
jbe@0 2350 PG_FREE_IF_COPY(query, 1); /* free detoasted cluster (if copy) */
jbe@0 2351 PG_RETURN_BOOL(retval);
jbe@0 2352 }
jbe@0 2353 /* throw error for any unknown strategy number */
jbe@0 2354 elog(ERROR, "unrecognized strategy number: %d", strategy);
jbe@0 2355 }
jbe@0 2356
jbe@0 2357 /* GiST "union" support function */
jbe@0 2358 PG_FUNCTION_INFO_V1(pgl_gist_union);
jbe@0 2359 Datum pgl_gist_union(PG_FUNCTION_ARGS) {
jbe@0 2360 GistEntryVector *entryvec = (GistEntryVector *)PG_GETARG_POINTER(0);
jbe@0 2361 pgl_keyptr out; /* return value (to be palloc'ed) */
jbe@0 2362 int i;
jbe@0 2363 /* determine key size */
jbe@0 2364 size_t keysize = PGL_KEY_IS_AREAKEY(
jbe@0 2365 (pgl_keyptr)DatumGetPointer(entryvec->vector[0].key)
jbe@0 2366 ) ? sizeof (pgl_areakey) : sizeof(pgl_pointkey);
jbe@0 2367 /* begin with first key as result */
jbe@0 2368 out = palloc(keysize);
jbe@0 2369 memcpy(out, (pgl_keyptr)DatumGetPointer(entryvec->vector[0].key), keysize);
jbe@0 2370 /* unite current result with second, third, etc. key */
jbe@0 2371 for (i=1; i<entryvec->n; i++) {
jbe@0 2372 pgl_unite_keys(out, (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key));
jbe@0 2373 }
jbe@0 2374 /* return result */
jbe@0 2375 PG_RETURN_POINTER(out);
jbe@0 2376 }
jbe@0 2377
jbe@0 2378 /* GiST "compress" support function for indicis on points */
jbe@0 2379 PG_FUNCTION_INFO_V1(pgl_gist_compress_epoint);
jbe@0 2380 Datum pgl_gist_compress_epoint(PG_FUNCTION_ARGS) {
jbe@0 2381 GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
jbe@0 2382 GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */
jbe@0 2383 /* only transform new leaves */
jbe@0 2384 if (entry->leafkey) {
jbe@0 2385 /* get point to be transformed */
jbe@0 2386 pgl_point *point = (pgl_point *)DatumGetPointer(entry->key);
jbe@0 2387 /* allocate memory for key */
jbe@0 2388 pgl_keyptr key = palloc(sizeof(pgl_pointkey));
jbe@0 2389 /* transform point to key */
jbe@0 2390 pgl_point_to_key(point, key);
jbe@0 2391 /* create new GISTENTRY structure as return value */
jbe@0 2392 retval = palloc(sizeof(GISTENTRY));
jbe@0 2393 gistentryinit(
jbe@0 2394 *retval, PointerGetDatum(key),
jbe@0 2395 entry->rel, entry->page, entry->offset, FALSE
jbe@0 2396 );
jbe@0 2397 } else {
jbe@0 2398 /* inner nodes have already been transformed */
jbe@0 2399 retval = entry;
jbe@0 2400 }
jbe@0 2401 /* return pointer to old or new GISTENTRY structure */
jbe@0 2402 PG_RETURN_POINTER(retval);
jbe@0 2403 }
jbe@0 2404
jbe@0 2405 /* GiST "compress" support function for indicis on circles */
jbe@0 2406 PG_FUNCTION_INFO_V1(pgl_gist_compress_ecircle);
jbe@0 2407 Datum pgl_gist_compress_ecircle(PG_FUNCTION_ARGS) {
jbe@0 2408 GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
jbe@0 2409 GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */
jbe@0 2410 /* only transform new leaves */
jbe@0 2411 if (entry->leafkey) {
jbe@0 2412 /* get circle to be transformed */
jbe@0 2413 pgl_circle *circle = (pgl_circle *)DatumGetPointer(entry->key);
jbe@0 2414 /* allocate memory for key */
jbe@0 2415 pgl_keyptr key = palloc(sizeof(pgl_areakey));
jbe@0 2416 /* transform circle to key */
jbe@0 2417 pgl_circle_to_key(circle, key);
jbe@0 2418 /* create new GISTENTRY structure as return value */
jbe@0 2419 retval = palloc(sizeof(GISTENTRY));
jbe@0 2420 gistentryinit(
jbe@0 2421 *retval, PointerGetDatum(key),
jbe@0 2422 entry->rel, entry->page, entry->offset, FALSE
jbe@0 2423 );
jbe@0 2424 } else {
jbe@0 2425 /* inner nodes have already been transformed */
jbe@0 2426 retval = entry;
jbe@0 2427 }
jbe@0 2428 /* return pointer to old or new GISTENTRY structure */
jbe@0 2429 PG_RETURN_POINTER(retval);
jbe@0 2430 }
jbe@0 2431
jbe@0 2432 /* GiST "compress" support function for indices on clusters */
jbe@0 2433 PG_FUNCTION_INFO_V1(pgl_gist_compress_ecluster);
jbe@0 2434 Datum pgl_gist_compress_ecluster(PG_FUNCTION_ARGS) {
jbe@0 2435 GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
jbe@0 2436 GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */
jbe@0 2437 /* only transform new leaves */
jbe@0 2438 if (entry->leafkey) {
jbe@0 2439 /* get cluster to be transformed (detoasting necessary!) */
jbe@0 2440 pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(entry->key);
jbe@0 2441 /* allocate memory for key */
jbe@0 2442 pgl_keyptr key = palloc(sizeof(pgl_areakey));
jbe@0 2443 /* transform cluster to key */
jbe@0 2444 pgl_circle_to_key(&(cluster->bounding), key);
jbe@0 2445 /* create new GISTENTRY structure as return value */
jbe@0 2446 retval = palloc(sizeof(GISTENTRY));
jbe@0 2447 gistentryinit(
jbe@0 2448 *retval, PointerGetDatum(key),
jbe@0 2449 entry->rel, entry->page, entry->offset, FALSE
jbe@0 2450 );
jbe@0 2451 /* free detoasted datum */
jbe@0 2452 if ((void *)cluster != (void *)DatumGetPointer(entry->key)) pfree(cluster);
jbe@0 2453 } else {
jbe@0 2454 /* inner nodes have already been transformed */
jbe@0 2455 retval = entry;
jbe@0 2456 }
jbe@0 2457 /* return pointer to old or new GISTENTRY structure */
jbe@0 2458 PG_RETURN_POINTER(retval);
jbe@0 2459 }
jbe@0 2460
jbe@0 2461 /* GiST "decompress" support function for indices */
jbe@0 2462 PG_FUNCTION_INFO_V1(pgl_gist_decompress);
jbe@0 2463 Datum pgl_gist_decompress(PG_FUNCTION_ARGS) {
jbe@0 2464 /* return passed pointer without transformation */
jbe@0 2465 PG_RETURN_POINTER(PG_GETARG_POINTER(0));
jbe@0 2466 }
jbe@0 2467
jbe@0 2468 /* GiST "penalty" support function */
jbe@0 2469 PG_FUNCTION_INFO_V1(pgl_gist_penalty);
jbe@0 2470 Datum pgl_gist_penalty(PG_FUNCTION_ARGS) {
jbe@0 2471 GISTENTRY *origentry = (GISTENTRY *)PG_GETARG_POINTER(0);
jbe@0 2472 GISTENTRY *newentry = (GISTENTRY *)PG_GETARG_POINTER(1);
jbe@0 2473 float *penalty = (float *)PG_GETARG_POINTER(2);
jbe@0 2474 /* get original key and key to insert */
jbe@0 2475 pgl_keyptr orig = (pgl_keyptr)DatumGetPointer(origentry->key);
jbe@0 2476 pgl_keyptr new = (pgl_keyptr)DatumGetPointer(newentry->key);
jbe@0 2477 /* copy original key */
jbe@0 2478 union { pgl_pointkey pointkey; pgl_areakey areakey; } union_key;
jbe@0 2479 if (PGL_KEY_IS_AREAKEY(orig)) {
jbe@0 2480 memcpy(union_key.areakey, orig, sizeof(union_key.areakey));
jbe@0 2481 } else {
jbe@0 2482 memcpy(union_key.pointkey, orig, sizeof(union_key.pointkey));
jbe@0 2483 }
jbe@0 2484 /* calculate union of both keys */
jbe@0 2485 pgl_unite_keys((pgl_keyptr)&union_key, new);
jbe@0 2486 /* penalty equal to reduction of key length (logarithm of added area) */
jbe@0 2487 /* (return value by setting referenced value and returning pointer) */
jbe@0 2488 *penalty = (
jbe@0 2489 PGL_KEY_NODEDEPTH(orig) - PGL_KEY_NODEDEPTH((pgl_keyptr)&union_key)
jbe@0 2490 );
jbe@0 2491 PG_RETURN_POINTER(penalty);
jbe@0 2492 }
jbe@0 2493
jbe@0 2494 /* GiST "picksplit" support function */
jbe@0 2495 PG_FUNCTION_INFO_V1(pgl_gist_picksplit);
jbe@0 2496 Datum pgl_gist_picksplit(PG_FUNCTION_ARGS) {
jbe@0 2497 GistEntryVector *entryvec = (GistEntryVector *)PG_GETARG_POINTER(0);
jbe@0 2498 GIST_SPLITVEC *v = (GIST_SPLITVEC *)PG_GETARG_POINTER(1);
jbe@0 2499 OffsetNumber i; /* between FirstOffsetNumber and entryvec->n (inclusive) */
jbe@0 2500 union {
jbe@0 2501 pgl_pointkey pointkey;
jbe@0 2502 pgl_areakey areakey;
jbe@0 2503 } union_all; /* union of all keys (to be calculated from scratch)
jbe@0 2504 (later cut in half) */
jbe@0 2505 int is_areakey = PGL_KEY_IS_AREAKEY(
jbe@0 2506 (pgl_keyptr)DatumGetPointer(entryvec->vector[FirstOffsetNumber].key)
jbe@0 2507 );
jbe@0 2508 int keysize = is_areakey ? sizeof(pgl_areakey) : sizeof(pgl_pointkey);
jbe@0 2509 pgl_keyptr unionL = palloc(keysize); /* union of keys that go left */
jbe@0 2510 pgl_keyptr unionR = palloc(keysize); /* union of keys that go right */
jbe@0 2511 pgl_keyptr key; /* current key to be processed */
jbe@0 2512 /* allocate memory for array of left and right keys, set counts to zero */
jbe@0 2513 v->spl_left = (OffsetNumber *)palloc(entryvec->n * sizeof(OffsetNumber));
jbe@0 2514 v->spl_nleft = 0;
jbe@0 2515 v->spl_right = (OffsetNumber *)palloc(entryvec->n * sizeof(OffsetNumber));
jbe@0 2516 v->spl_nright = 0;
jbe@0 2517 /* calculate union of all keys from scratch */
jbe@0 2518 memcpy(
jbe@0 2519 (pgl_keyptr)&union_all,
jbe@0 2520 (pgl_keyptr)DatumGetPointer(entryvec->vector[FirstOffsetNumber].key),
jbe@0 2521 keysize
jbe@0 2522 );
jbe@0 2523 for (i=FirstOffsetNumber+1; i<entryvec->n; i=OffsetNumberNext(i)) {
jbe@0 2524 pgl_unite_keys(
jbe@0 2525 (pgl_keyptr)&union_all,
jbe@0 2526 (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key)
jbe@0 2527 );
jbe@0 2528 }
jbe@0 2529 /* check if trivial split is necessary due to exhausted key length */
jbe@0 2530 /* (Note: keys for empty objects must have node depth set to maximum) */
jbe@0 2531 if (PGL_KEY_NODEDEPTH((pgl_keyptr)&union_all) == (
jbe@0 2532 is_areakey ? PGL_AREAKEY_MAXDEPTH : PGL_POINTKEY_MAXDEPTH
jbe@0 2533 )) {
jbe@0 2534 /* half of all keys go left */
jbe@0 2535 for (
jbe@0 2536 i=FirstOffsetNumber;
jbe@0 2537 i<FirstOffsetNumber+(entryvec->n - FirstOffsetNumber)/2;
jbe@0 2538 i=OffsetNumberNext(i)
jbe@0 2539 ) {
jbe@0 2540 /* pointer to current key */
jbe@0 2541 key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key);
jbe@0 2542 /* update unionL */
jbe@0 2543 /* check if key is first key that goes left */
jbe@0 2544 if (!v->spl_nleft) {
jbe@0 2545 /* first key that goes left is just copied to unionL */
jbe@0 2546 memcpy(unionL, key, keysize);
jbe@0 2547 } else {
jbe@0 2548 /* unite current value and next key */
jbe@0 2549 pgl_unite_keys(unionL, key);
jbe@0 2550 }
jbe@0 2551 /* append offset number to list of keys that go left */
jbe@0 2552 v->spl_left[v->spl_nleft++] = i;
jbe@0 2553 }
jbe@0 2554 /* other half goes right */
jbe@0 2555 for (
jbe@0 2556 i=FirstOffsetNumber+(entryvec->n - FirstOffsetNumber)/2;
jbe@0 2557 i<entryvec->n;
jbe@0 2558 i=OffsetNumberNext(i)
jbe@0 2559 ) {
jbe@0 2560 /* pointer to current key */
jbe@0 2561 key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key);
jbe@0 2562 /* update unionR */
jbe@0 2563 /* check if key is first key that goes right */
jbe@0 2564 if (!v->spl_nright) {
jbe@0 2565 /* first key that goes right is just copied to unionR */
jbe@0 2566 memcpy(unionR, key, keysize);
jbe@0 2567 } else {
jbe@0 2568 /* unite current value and next key */
jbe@0 2569 pgl_unite_keys(unionR, key);
jbe@0 2570 }
jbe@0 2571 /* append offset number to list of keys that go right */
jbe@0 2572 v->spl_right[v->spl_nright++] = i;
jbe@0 2573 }
jbe@0 2574 }
jbe@0 2575 /* otherwise, a non-trivial split is possible */
jbe@0 2576 else {
jbe@0 2577 /* cut covered area in half */
jbe@0 2578 /* (union_all then refers to area of keys that go left) */
jbe@0 2579 /* check if union of all keys covers empty and non-empty objects */
jbe@0 2580 if (PGL_KEY_IS_UNIVERSAL((pgl_keyptr)&union_all)) {
jbe@0 2581 /* if yes, split into empty and non-empty objects */
jbe@0 2582 pgl_key_set_empty((pgl_keyptr)&union_all);
jbe@0 2583 } else {
jbe@0 2584 /* otherwise split by next bit */
jbe@0 2585 ((pgl_keyptr)&union_all)[PGL_KEY_NODEDEPTH_OFFSET]++;
jbe@0 2586 /* NOTE: type bit conserved */
jbe@0 2587 }
jbe@0 2588 /* determine for each key if it goes left or right */
jbe@0 2589 for (i=FirstOffsetNumber; i<entryvec->n; i=OffsetNumberNext(i)) {
jbe@0 2590 /* pointer to current key */
jbe@0 2591 key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key);
jbe@0 2592 /* keys within one half of the area go left */
jbe@0 2593 if (pgl_keys_overlap((pgl_keyptr)&union_all, key)) {
jbe@0 2594 /* update unionL */
jbe@0 2595 /* check if key is first key that goes left */
jbe@0 2596 if (!v->spl_nleft) {
jbe@0 2597 /* first key that goes left is just copied to unionL */
jbe@0 2598 memcpy(unionL, key, keysize);
jbe@0 2599 } else {
jbe@0 2600 /* unite current value of unionL and processed key */
jbe@0 2601 pgl_unite_keys(unionL, key);
jbe@0 2602 }
jbe@0 2603 /* append offset number to list of keys that go left */
jbe@0 2604 v->spl_left[v->spl_nleft++] = i;
jbe@0 2605 }
jbe@0 2606 /* the other keys go right */
jbe@0 2607 else {
jbe@0 2608 /* update unionR */
jbe@0 2609 /* check if key is first key that goes right */
jbe@0 2610 if (!v->spl_nright) {
jbe@0 2611 /* first key that goes right is just copied to unionR */
jbe@0 2612 memcpy(unionR, key, keysize);
jbe@0 2613 } else {
jbe@0 2614 /* unite current value of unionR and processed key */
jbe@0 2615 pgl_unite_keys(unionR, key);
jbe@0 2616 }
jbe@0 2617 /* append offset number to list of keys that go right */
jbe@0 2618 v->spl_right[v->spl_nright++] = i;
jbe@0 2619 }
jbe@0 2620 }
jbe@0 2621 }
jbe@0 2622 /* store unions in return value */
jbe@0 2623 v->spl_ldatum = PointerGetDatum(unionL);
jbe@0 2624 v->spl_rdatum = PointerGetDatum(unionR);
jbe@0 2625 /* return all results */
jbe@0 2626 PG_RETURN_POINTER(v);
jbe@0 2627 }
jbe@0 2628
jbe@0 2629 /* GiST "same"/"equal" support function */
jbe@0 2630 PG_FUNCTION_INFO_V1(pgl_gist_same);
jbe@0 2631 Datum pgl_gist_same(PG_FUNCTION_ARGS) {
jbe@0 2632 pgl_keyptr key1 = (pgl_keyptr)PG_GETARG_POINTER(0);
jbe@0 2633 pgl_keyptr key2 = (pgl_keyptr)PG_GETARG_POINTER(1);
jbe@0 2634 bool *boolptr = (bool *)PG_GETARG_POINTER(2);
jbe@0 2635 /* two keys are equal if they are binary equal */
jbe@0 2636 /* (return result by setting referenced boolean and returning pointer) */
jbe@0 2637 *boolptr = !memcmp(
jbe@0 2638 key1,
jbe@0 2639 key2,
jbe@0 2640 PGL_KEY_IS_AREAKEY(key1) ? sizeof(pgl_areakey) : sizeof(pgl_pointkey)
jbe@0 2641 );
jbe@0 2642 PG_RETURN_POINTER(boolptr);
jbe@0 2643 }
jbe@0 2644
jbe@0 2645 /* GiST "distance" support function */
jbe@0 2646 PG_FUNCTION_INFO_V1(pgl_gist_distance);
jbe@0 2647 Datum pgl_gist_distance(PG_FUNCTION_ARGS) {
jbe@0 2648 GISTENTRY *entry = (GISTENTRY *)PG_GETARG_POINTER(0);
jbe@0 2649 pgl_keyptr key = (pgl_keyptr)DatumGetPointer(entry->key);
jbe@0 2650 StrategyNumber strategy = (StrategyNumber)PG_GETARG_UINT16(2);
jbe@0 2651 bool *recheck = (bool *)PG_GETARG_POINTER(4);
jbe@0 2652 double distance; /* return value */
jbe@0 2653 /* demand recheck because distance is just an estimation */
jbe@0 2654 /* (real distance may be bigger) */
jbe@0 2655 *recheck = true;
jbe@0 2656 /* strategy number 31: distance to point */
jbe@0 2657 if (strategy == 31) {
jbe@0 2658 /* query datum is a point */
jbe@0 2659 pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1);
jbe@0 2660 /* use pgl_estimate_pointkey_distance() function to compute result */
jbe@0 2661 distance = pgl_estimate_key_distance(key, query);
jbe@0 2662 /* avoid infinity (reserved!) */
jbe@0 2663 if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE;
jbe@0 2664 /* return result */
jbe@0 2665 PG_RETURN_FLOAT8(distance);
jbe@0 2666 }
jbe@0 2667 /* strategy number 33: distance to circle */
jbe@0 2668 if (strategy == 33) {
jbe@0 2669 /* query datum is a circle */
jbe@0 2670 pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1);
jbe@0 2671 /* estimate distance to circle center and substract circle radius */
jbe@0 2672 distance = (
jbe@0 2673 pgl_estimate_key_distance(key, &(query->center)) - query->radius
jbe@0 2674 );
jbe@0 2675 /* convert non-positive values to zero and avoid infinity (reserved!) */
jbe@0 2676 if (distance <= 0) distance = 0;
jbe@0 2677 else if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE;
jbe@0 2678 /* return result */
jbe@0 2679 PG_RETURN_FLOAT8(distance);
jbe@0 2680 }
jbe@0 2681 /* strategy number 34: distance to cluster */
jbe@0 2682 if (strategy == 34) {
jbe@0 2683 /* query datum is a cluster */
jbe@0 2684 pgl_cluster *query = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1));
jbe@0 2685 /* estimate distance to bounding center and substract bounding radius */
jbe@0 2686 distance = (
jbe@0 2687 pgl_estimate_key_distance(key, &(query->bounding.center)) -
jbe@0 2688 query->bounding.radius
jbe@0 2689 );
jbe@0 2690 /* convert non-positive values to zero and avoid infinity (reserved!) */
jbe@0 2691 if (distance <= 0) distance = 0;
jbe@0 2692 else if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE;
jbe@0 2693 /* free detoasted cluster (if copy) */
jbe@0 2694 PG_FREE_IF_COPY(query, 1);
jbe@0 2695 /* return result */
jbe@0 2696 PG_RETURN_FLOAT8(distance);
jbe@0 2697 }
jbe@0 2698 /* throw error for any unknown strategy number */
jbe@0 2699 elog(ERROR, "unrecognized strategy number: %d", strategy);
jbe@0 2700 }
jbe@0 2701

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