pgLatLon
diff latlon-v0001.c @ 0:3b70e93cc07d
Version 0.1 (initial commit)
| author | jbe |
|---|---|
| date | Sun Aug 21 17:43:48 2016 +0200 (2016-08-21) |
| parents | |
| children |
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1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/latlon-v0001.c Sun Aug 21 17:43:48 2016 +0200 1.3 @@ -0,0 +1,2710 @@ 1.4 + 1.5 +/*-------------* 1.6 + * C prelude * 1.7 + *-------------*/ 1.8 + 1.9 +#include "postgres.h" 1.10 +#include "fmgr.h" 1.11 +#include "libpq/pqformat.h" 1.12 +#include "access/gist.h" 1.13 +#include "access/stratnum.h" 1.14 +#include "utils/array.h" 1.15 +#include <math.h> 1.16 + 1.17 +#ifdef PG_MODULE_MAGIC 1.18 +PG_MODULE_MAGIC; 1.19 +#endif 1.20 + 1.21 +#if INT_MAX < 2147483647 1.22 +#error Expected int type to be at least 32 bit wide 1.23 +#endif 1.24 + 1.25 + 1.26 +/*---------------------------------* 1.27 + * distance calculation on earth * 1.28 + * (using WGS-84 spheroid) * 1.29 + *---------------------------------*/ 1.30 + 1.31 +/* WGS-84 spheroid with following parameters: 1.32 + semi-major axis a = 6378137 1.33 + semi-minor axis b = a * (1 - 1/298.257223563) 1.34 + estimated diameter = 2 * (2*a+b)/3 1.35 +*/ 1.36 +#define PGL_SPHEROID_A 6378137.0 /* semi major axis */ 1.37 +#define PGL_SPHEROID_F (1.0/298.257223563) /* flattening */ 1.38 +#define PGL_SPHEROID_B (PGL_SPHEROID_A * (1.0-PGL_SPHEROID_F)) 1.39 +#define PGL_EPS2 ( ( PGL_SPHEROID_A * PGL_SPHEROID_A - \ 1.40 + PGL_SPHEROID_B * PGL_SPHEROID_B ) / \ 1.41 + ( PGL_SPHEROID_A * PGL_SPHEROID_A ) ) 1.42 +#define PGL_SUBEPS2 (1.0-PGL_EPS2) 1.43 +#define PGL_DIAMETER ((4.0*PGL_SPHEROID_A + 2.0*PGL_SPHEROID_B) / 3.0) 1.44 +#define PGL_SCALE (PGL_SPHEROID_A / PGL_DIAMETER) /* semi-major ref. */ 1.45 +#define PGL_FADELIMIT (PGL_DIAMETER * M_PI / 6.0) /* 1/6 circumference */ 1.46 +#define PGL_MAXDIST (PGL_DIAMETER * M_PI / 2.0) /* maximum distance */ 1.47 + 1.48 +/* calculate distance between two points on earth (given in degrees) */ 1.49 +static inline double pgl_distance( 1.50 + double lat1, double lon1, double lat2, double lon2 1.51 +) { 1.52 + float8 lat1cos, lat1sin, lat2cos, lat2sin, lon2cos, lon2sin; 1.53 + float8 nphi1, nphi2, x1, z1, x2, y2, z2, g, s, t; 1.54 + /* normalize delta longitude (lon2 > 0 && lon1 = 0) */ 1.55 + /* lon1 = 0 (not used anymore) */ 1.56 + lon2 = fabs(lon2-lon1); 1.57 + /* convert to radians (first divide, then multiply) */ 1.58 + lat1 = (lat1 / 180.0) * M_PI; 1.59 + lat2 = (lat2 / 180.0) * M_PI; 1.60 + lon2 = (lon2 / 180.0) * M_PI; 1.61 + /* make lat2 >= lat1 to ensure reversal-symmetry despite floating point 1.62 + operations (lon2 >= lon1 is already ensured in a previous step) */ 1.63 + if (lat2 < lat1) { float8 swap = lat1; lat1 = lat2; lat2 = swap; } 1.64 + /* calculate 3d coordinates on scaled ellipsoid which has an average diameter 1.65 + of 1.0 */ 1.66 + lat1cos = cos(lat1); lat1sin = sin(lat1); 1.67 + lat2cos = cos(lat2); lat2sin = sin(lat2); 1.68 + lon2cos = cos(lon2); lon2sin = sin(lon2); 1.69 + nphi1 = PGL_SCALE / sqrt(1 - PGL_EPS2 * lat1sin * lat1sin); 1.70 + nphi2 = PGL_SCALE / sqrt(1 - PGL_EPS2 * lat2sin * lat2sin); 1.71 + x1 = nphi1 * lat1cos; 1.72 + z1 = nphi1 * PGL_SUBEPS2 * lat1sin; 1.73 + x2 = nphi2 * lat2cos * lon2cos; 1.74 + y2 = nphi2 * lat2cos * lon2sin; 1.75 + z2 = nphi2 * PGL_SUBEPS2 * lat2sin; 1.76 + /* calculate tunnel distance through scaled (diameter 1.0) ellipsoid */ 1.77 + g = sqrt((x2-x1)*(x2-x1) + y2*y2 + (z2-z1)*(z2-z1)); 1.78 + /* convert tunnel distance through scaled ellipsoid to approximated surface 1.79 + distance on original ellipsoid */ 1.80 + if (g > 1.0) g = 1.0; 1.81 + s = PGL_DIAMETER * asin(g); 1.82 + /* return result only if small enough to be precise (less than 1/3 of 1.83 + maximum possible distance) */ 1.84 + if (s <= PGL_FADELIMIT) return s; 1.85 + /* determine antipodal point of second point (i.e. mirror second point) */ 1.86 + lat2 = -lat2; lon2 = lon2 - M_PI; 1.87 + lat2cos = cos(lat2); lat2sin = sin(lat2); 1.88 + lon2cos = cos(lon2); lon2sin = sin(lon2); 1.89 + /* calculate 3d coordinates of antipodal point on scaled ellipsoid */ 1.90 + nphi2 = PGL_SCALE / sqrt(1 - PGL_EPS2 * lat2sin * lat2sin); 1.91 + x2 = nphi2 * lat2cos * lon2cos; 1.92 + y2 = nphi2 * lat2cos * lon2sin; 1.93 + z2 = nphi2 * PGL_SUBEPS2 * lat2sin; 1.94 + /* calculate tunnel distance to antipodal point through scaled ellipsoid */ 1.95 + g = sqrt((x2-x1)*(x2-x1) + y2*y2 + (z2-z1)*(z2-z1)); 1.96 + /* convert tunnel distance to antipodal point through scaled ellipsoid to 1.97 + approximated surface distance to antipodal point on original ellipsoid */ 1.98 + if (g > 1.0) g = 1.0; 1.99 + t = PGL_DIAMETER * asin(g); 1.100 + /* surface distance between original points can now be approximated by 1.101 + substracting antipodal distance from maximum possible distance; 1.102 + return result only if small enough (less than 1/3 of maximum possible 1.103 + distance) */ 1.104 + if (t <= PGL_FADELIMIT) return PGL_MAXDIST-t; 1.105 + /* otherwise crossfade direct and antipodal result to ensure monotonicity */ 1.106 + return ( 1.107 + (s * (t-PGL_FADELIMIT) + (PGL_MAXDIST-t) * (s-PGL_FADELIMIT)) / 1.108 + (s + t - 2*PGL_FADELIMIT) 1.109 + ); 1.110 +} 1.111 + 1.112 +/* finite distance that can not be reached on earth */ 1.113 +#define PGL_ULTRA_DISTANCE (3 * PGL_MAXDIST) 1.114 + 1.115 + 1.116 +/*--------------------------------* 1.117 + * simple geographic data types * 1.118 + *--------------------------------*/ 1.119 + 1.120 +/* point on earth given by latitude and longitude in degrees */ 1.121 +/* (type "epoint" in SQL) */ 1.122 +typedef struct { 1.123 + double lat; /* between -90 and 90 (both inclusive) */ 1.124 + double lon; /* between -180 and 180 (both inclusive) */ 1.125 +} pgl_point; 1.126 + 1.127 +/* box delimited by two parallels and two meridians (all in degrees) */ 1.128 +/* (type "ebox" in SQL) */ 1.129 +typedef struct { 1.130 + double lat_min; /* between -90 and 90 (both inclusive) */ 1.131 + double lat_max; /* between -90 and 90 (both inclusive) */ 1.132 + double lon_min; /* between -180 and 180 (both inclusive) */ 1.133 + double lon_max; /* between -180 and 180 (both inclusive) */ 1.134 + /* if lat_min > lat_max, then box is empty */ 1.135 + /* if lon_min > lon_max, then 180th meridian is crossed */ 1.136 +} pgl_box; 1.137 + 1.138 +/* circle on earth surface (for radial searches with fixed radius) */ 1.139 +/* (type "ecircle" in SQL) */ 1.140 +typedef struct { 1.141 + pgl_point center; 1.142 + double radius; /* positive (including +0 but excluding -0), or -INFINITY */ 1.143 + /* A negative radius (i.e. -INFINITY) denotes nothing (i.e. no point), 1.144 + zero radius (0) denotes a single point, 1.145 + a finite radius (0 < radius < INFINITY) denotes a filled circle, and 1.146 + a radius of INFINITY is valid and means complete coverage of earth. */ 1.147 +} pgl_circle; 1.148 + 1.149 + 1.150 +/*----------------------------------* 1.151 + * geographic "cluster" data type * 1.152 + *----------------------------------*/ 1.153 + 1.154 +/* A cluster is a collection of points, paths, outlines, and polygons. If two 1.155 + polygons in a cluster overlap, the area covered by both polygons does not 1.156 + belong to the cluster. This way, a cluster can be used to describe complex 1.157 + shapes like polygons with holes. Outlines are non-filled polygons. Paths are 1.158 + open by default (i.e. the last point in the list is not connected with the 1.159 + first point in the list). Note that each outline or polygon in a cluster 1.160 + must cover a longitude range of less than 180 degrees to avoid ambiguities. 1.161 + Areas which are larger may be split into multiple polygons. */ 1.162 + 1.163 +/* maximum number of points in a cluster */ 1.164 +/* (limited to avoid integer overflows, e.g. when allocating memory) */ 1.165 +#define PGL_CLUSTER_MAXPOINTS 16777216 1.166 + 1.167 +/* types of cluster entries */ 1.168 +#define PGL_ENTRY_POINT 1 /* a point */ 1.169 +#define PGL_ENTRY_PATH 2 /* a path from first point to last point */ 1.170 +#define PGL_ENTRY_OUTLINE 3 /* a non-filled polygon with given vertices */ 1.171 +#define PGL_ENTRY_POLYGON 4 /* a filled polygon with given vertices */ 1.172 + 1.173 +/* Entries of a cluster are described by two different structs: pgl_newentry 1.174 + and pgl_entry. The first is used only during construction of a cluster, the 1.175 + second is used in all other cases (e.g. when reading clusters from the 1.176 + database, performing operations, etc). */ 1.177 + 1.178 +/* entry for new geographic cluster during construction of that cluster */ 1.179 +typedef struct { 1.180 + int32_t entrytype; 1.181 + int32_t npoints; 1.182 + pgl_point *points; /* pointer to an array of points (pgl_point) */ 1.183 +} pgl_newentry; 1.184 + 1.185 +/* entry of geographic cluster */ 1.186 +typedef struct { 1.187 + int32_t entrytype; /* type of entry: point, path, outline, polygon */ 1.188 + int32_t npoints; /* number of stored points (set to 1 for point entry) */ 1.189 + int32_t offset; /* offset of pgl_point array from cluster base address */ 1.190 + /* use macro PGL_ENTRY_POINTS to obtain a pointer to the array of points */ 1.191 +} pgl_entry; 1.192 + 1.193 +/* geographic cluster which is a collection of points, (open) paths, polygons, 1.194 + and outlines (non-filled polygons) */ 1.195 +typedef struct { 1.196 + char header[VARHDRSZ]; /* PostgreSQL header for variable size data types */ 1.197 + int32_t nentries; /* number of stored points */ 1.198 + pgl_circle bounding; /* bounding circle */ 1.199 + /* Note: bounding circle ensures alignment of pgl_cluster for points */ 1.200 + pgl_entry entries[FLEXIBLE_ARRAY_MEMBER]; /* var-length data */ 1.201 +} pgl_cluster; 1.202 + 1.203 +/* macro to determine memory alignment of points */ 1.204 +/* (needed to store pgl_point array after entries in pgl_cluster) */ 1.205 +typedef struct { char dummy; pgl_point aligned; } pgl_point_alignment; 1.206 +#define PGL_POINT_ALIGNMENT offsetof(pgl_point_alignment, aligned) 1.207 + 1.208 +/* macro to extract a pointer to the array of points of a cluster entry */ 1.209 +#define PGL_ENTRY_POINTS(cluster, idx) \ 1.210 + ((pgl_point *)(((intptr_t)cluster)+(cluster)->entries[idx].offset)) 1.211 + 1.212 +/* convert pgl_newentry array to pgl_cluster */ 1.213 +static pgl_cluster *pgl_new_cluster(int nentries, pgl_newentry *entries) { 1.214 + int i; /* index of current entry */ 1.215 + int npoints = 0; /* number of points in whole cluster */ 1.216 + int entry_npoints; /* number of points in current entry */ 1.217 + int points_offset = PGL_POINT_ALIGNMENT * ( 1.218 + ( offsetof(pgl_cluster, entries) + 1.219 + nentries * sizeof(pgl_entry) + 1.220 + PGL_POINT_ALIGNMENT - 1 1.221 + ) / PGL_POINT_ALIGNMENT 1.222 + ); /* offset of pgl_point array from base address (considering alignment) */ 1.223 + pgl_cluster *cluster; /* new cluster to be returned */ 1.224 + /* determine total number of points */ 1.225 + for (i=0; i<nentries; i++) npoints += entries[i].npoints; 1.226 + /* allocate memory for cluster (including entries and points) */ 1.227 + cluster = palloc(points_offset + npoints * sizeof(pgl_point)); 1.228 + /* re-count total number of points to determine offset for each entry */ 1.229 + npoints = 0; 1.230 + /* copy entries and points */ 1.231 + for (i=0; i<nentries; i++) { 1.232 + /* determine number of points in entry */ 1.233 + entry_npoints = entries[i].npoints; 1.234 + /* copy entry */ 1.235 + cluster->entries[i].entrytype = entries[i].entrytype; 1.236 + cluster->entries[i].npoints = entry_npoints; 1.237 + /* calculate offset (in bytes) of pgl_point array */ 1.238 + cluster->entries[i].offset = points_offset + npoints * sizeof(pgl_point); 1.239 + /* copy points */ 1.240 + memcpy( 1.241 + PGL_ENTRY_POINTS(cluster, i), 1.242 + entries[i].points, 1.243 + entry_npoints * sizeof(pgl_point) 1.244 + ); 1.245 + /* update total number of points processed */ 1.246 + npoints += entry_npoints; 1.247 + } 1.248 + /* set number of entries in cluster */ 1.249 + cluster->nentries = nentries; 1.250 + /* set PostgreSQL header for variable sized data */ 1.251 + SET_VARSIZE(cluster, points_offset + npoints * sizeof(pgl_point)); 1.252 + /* return newly created cluster */ 1.253 + return cluster; 1.254 +} 1.255 + 1.256 + 1.257 +/*----------------------------------------* 1.258 + * C functions on geographic data types * 1.259 + *----------------------------------------*/ 1.260 + 1.261 +/* round latitude or longitude to 12 digits after decimal point */ 1.262 +static inline double pgl_round(double val) { 1.263 + return round(val * 1e12) / 1e12; 1.264 +} 1.265 + 1.266 +/* compare two points */ 1.267 +/* (equality when same point on earth is described, otherwise an arbitrary 1.268 + linear order) */ 1.269 +static int pgl_point_cmp(pgl_point *point1, pgl_point *point2) { 1.270 + double lon1, lon2; /* modified longitudes for special cases */ 1.271 + /* use latitude as first ordering criterion */ 1.272 + if (point1->lat < point2->lat) return -1; 1.273 + if (point1->lat > point2->lat) return 1; 1.274 + /* determine modified longitudes (considering special case of poles and 1.275 + 180th meridian which can be described as W180 or E180) */ 1.276 + if (point1->lat == -90 || point1->lat == 90) lon1 = 0; 1.277 + else if (point1->lon == 180) lon1 = -180; 1.278 + else lon1 = point1->lon; 1.279 + if (point2->lat == -90 || point2->lat == 90) lon2 = 0; 1.280 + else if (point2->lon == 180) lon2 = -180; 1.281 + else lon2 = point2->lon; 1.282 + /* use (modified) longitude as secondary ordering criterion */ 1.283 + if (lon1 < lon2) return -1; 1.284 + if (lon1 > lon2) return 1; 1.285 + /* no difference found, points are equal */ 1.286 + return 0; 1.287 +} 1.288 + 1.289 +/* compare two boxes */ 1.290 +/* (equality when same box on earth is described, otherwise an arbitrary linear 1.291 + order) */ 1.292 +static int pgl_box_cmp(pgl_box *box1, pgl_box *box2) { 1.293 + /* two empty boxes are equal, and an empty box is always considered "less 1.294 + than" a non-empty box */ 1.295 + if (box1->lat_min> box1->lat_max && box2->lat_min<=box2->lat_max) return -1; 1.296 + if (box1->lat_min> box1->lat_max && box2->lat_min> box2->lat_max) return 0; 1.297 + if (box1->lat_min<=box1->lat_max && box2->lat_min> box2->lat_max) return 1; 1.298 + /* use southern border as first ordering criterion */ 1.299 + if (box1->lat_min < box2->lat_min) return -1; 1.300 + if (box1->lat_min > box2->lat_min) return 1; 1.301 + /* use northern border as second ordering criterion */ 1.302 + if (box1->lat_max < box2->lat_max) return -1; 1.303 + if (box1->lat_max > box2->lat_max) return 1; 1.304 + /* use western border as third ordering criterion */ 1.305 + if (box1->lon_min < box2->lon_min) return -1; 1.306 + if (box1->lon_min > box2->lon_min) return 1; 1.307 + /* use eastern border as fourth ordering criterion */ 1.308 + if (box1->lon_max < box2->lon_max) return -1; 1.309 + if (box1->lon_max > box2->lon_max) return 1; 1.310 + /* no difference found, boxes are equal */ 1.311 + return 0; 1.312 +} 1.313 + 1.314 +/* compare two circles */ 1.315 +/* (equality when same circle on earth is described, otherwise an arbitrary 1.316 + linear order) */ 1.317 +static int pgl_circle_cmp(pgl_circle *circle1, pgl_circle *circle2) { 1.318 + /* two circles with same infinite radius (positive or negative infinity) are 1.319 + considered equal independently of center point */ 1.320 + if ( 1.321 + !isfinite(circle1->radius) && !isfinite(circle2->radius) && 1.322 + circle1->radius == circle2->radius 1.323 + ) return 0; 1.324 + /* use radius as first ordering criterion */ 1.325 + if (circle1->radius < circle2->radius) return -1; 1.326 + if (circle1->radius > circle2->radius) return 1; 1.327 + /* use center point as secondary ordering criterion */ 1.328 + return pgl_point_cmp(&(circle1->center), &(circle2->center)); 1.329 +} 1.330 + 1.331 +/* set box to empty box*/ 1.332 +static void pgl_box_set_empty(pgl_box *box) { 1.333 + box->lat_min = INFINITY; 1.334 + box->lat_max = -INFINITY; 1.335 + box->lon_min = 0; 1.336 + box->lon_max = 0; 1.337 +} 1.338 + 1.339 +/* check if point is inside a box */ 1.340 +static bool pgl_point_in_box(pgl_point *point, pgl_box *box) { 1.341 + return ( 1.342 + point->lat >= box->lat_min && point->lat <= box->lat_max && ( 1.343 + (box->lon_min > box->lon_max) ? ( 1.344 + /* box crosses 180th meridian */ 1.345 + point->lon >= box->lon_min || point->lon <= box->lon_max 1.346 + ) : ( 1.347 + /* box does not cross the 180th meridian */ 1.348 + point->lon >= box->lon_min && point->lon <= box->lon_max 1.349 + ) 1.350 + ) 1.351 + ); 1.352 +} 1.353 + 1.354 +/* check if two boxes overlap */ 1.355 +static bool pgl_boxes_overlap(pgl_box *box1, pgl_box *box2) { 1.356 + return ( 1.357 + box2->lat_max >= box2->lat_min && /* ensure box2 is not empty */ 1.358 + ( box2->lat_min >= box1->lat_min || box2->lat_max >= box1->lat_min ) && 1.359 + ( box2->lat_min <= box1->lat_max || box2->lat_max <= box1->lat_max ) && ( 1.360 + ( 1.361 + /* check if one and only one box crosses the 180th meridian */ 1.362 + ((box1->lon_min > box1->lon_max) ? 1 : 0) ^ 1.363 + ((box2->lon_min > box2->lon_max) ? 1 : 0) 1.364 + ) ? ( 1.365 + /* exactly one box crosses the 180th meridian */ 1.366 + box2->lon_min >= box1->lon_min || box2->lon_max >= box1->lon_min || 1.367 + box2->lon_min <= box1->lon_max || box2->lon_max <= box1->lon_max 1.368 + ) : ( 1.369 + /* no box or both boxes cross the 180th meridian */ 1.370 + ( 1.371 + (box2->lon_min >= box1->lon_min || box2->lon_max >= box1->lon_min) && 1.372 + (box2->lon_min <= box1->lon_max || box2->lon_max <= box1->lon_max) 1.373 + ) || 1.374 + /* handle W180 == E180 */ 1.375 + ( box1->lon_min == -180 && box2->lon_max == 180 ) || 1.376 + ( box2->lon_min == -180 && box1->lon_max == 180 ) 1.377 + ) 1.378 + ) 1.379 + ); 1.380 +} 1.381 + 1.382 +/* check unambiguousness of east/west orientation of cluster entries and set 1.383 + bounding circle of cluster */ 1.384 +static bool pgl_finalize_cluster(pgl_cluster *cluster) { 1.385 + int i, j; /* i: index of entry, j: index of point in entry */ 1.386 + int npoints; /* number of points in entry */ 1.387 + int total_npoints = 0; /* total number of points in cluster */ 1.388 + pgl_point *points; /* points in entry */ 1.389 + int lon_dir; /* first point of entry west (-1) or east (+1) */ 1.390 + double lon_break = 0; /* antipodal longitude of first point in entry */ 1.391 + double lon_min, lon_max; /* covered longitude range of entry */ 1.392 + double value; /* temporary variable */ 1.393 + /* reset bounding circle center to empty circle at 0/0 coordinates */ 1.394 + cluster->bounding.center.lat = 0; 1.395 + cluster->bounding.center.lon = 0; 1.396 + cluster->bounding.radius = -INFINITY; 1.397 + /* if cluster is not empty */ 1.398 + if (cluster->nentries != 0) { 1.399 + /* iterate over all cluster entries and ensure they each cover a longitude 1.400 + range less than 180 degrees */ 1.401 + for (i=0; i<cluster->nentries; i++) { 1.402 + /* get properties of entry */ 1.403 + npoints = cluster->entries[i].npoints; 1.404 + points = PGL_ENTRY_POINTS(cluster, i); 1.405 + /* get longitude of first point of entry */ 1.406 + value = points[0].lon; 1.407 + /* initialize lon_min and lon_max with longitude of first point */ 1.408 + lon_min = value; 1.409 + lon_max = value; 1.410 + /* determine east/west orientation of first point and calculate antipodal 1.411 + longitude (Note: rounding required here) */ 1.412 + if (value < 0) { lon_dir = -1; lon_break = pgl_round(value + 180); } 1.413 + else if (value > 0) { lon_dir = 1; lon_break = pgl_round(value - 180); } 1.414 + else lon_dir = 0; 1.415 + /* iterate over all other points in entry */ 1.416 + for (j=1; j<npoints; j++) { 1.417 + /* consider longitude wrap-around */ 1.418 + value = points[j].lon; 1.419 + if (lon_dir<0 && value>lon_break) value = pgl_round(value - 360); 1.420 + else if (lon_dir>0 && value<lon_break) value = pgl_round(value + 360); 1.421 + /* update lon_min and lon_max */ 1.422 + if (value < lon_min) lon_min = value; 1.423 + else if (value > lon_max) lon_max = value; 1.424 + /* return false if 180 degrees or more are covered */ 1.425 + if (lon_max - lon_min >= 180) return false; 1.426 + } 1.427 + } 1.428 + /* iterate over all points of all entries and calculate arbitrary center 1.429 + point for bounding circle (best if center point minimizes the radius, 1.430 + but some error is allowed here) */ 1.431 + for (i=0; i<cluster->nentries; i++) { 1.432 + /* get properties of entry */ 1.433 + npoints = cluster->entries[i].npoints; 1.434 + points = PGL_ENTRY_POINTS(cluster, i); 1.435 + /* check if first entry */ 1.436 + if (i==0) { 1.437 + /* get longitude of first point of first entry in whole cluster */ 1.438 + value = points[0].lon; 1.439 + /* initialize lon_min and lon_max with longitude of first point of 1.440 + first entry in whole cluster (used to determine if whole cluster 1.441 + covers a longitude range of 180 degrees or more) */ 1.442 + lon_min = value; 1.443 + lon_max = value; 1.444 + /* determine east/west orientation of first point and calculate 1.445 + antipodal longitude (Note: rounding not necessary here) */ 1.446 + if (value < 0) { lon_dir = -1; lon_break = value + 180; } 1.447 + else if (value > 0) { lon_dir = 1; lon_break = value - 180; } 1.448 + else lon_dir = 0; 1.449 + } 1.450 + /* iterate over all points in entry */ 1.451 + for (j=0; j<npoints; j++) { 1.452 + /* longitude wrap-around (Note: rounding not necessary here) */ 1.453 + value = points[j].lon; 1.454 + if (lon_dir < 0 && value > lon_break) value -= 360; 1.455 + else if (lon_dir > 0 && value < lon_break) value += 360; 1.456 + if (value < lon_min) lon_min = value; 1.457 + else if (value > lon_max) lon_max = value; 1.458 + /* set bounding circle to cover whole earth if more than 180 degrees 1.459 + are covered */ 1.460 + if (lon_max - lon_min >= 180) { 1.461 + cluster->bounding.center.lat = 0; 1.462 + cluster->bounding.center.lon = 0; 1.463 + cluster->bounding.radius = INFINITY; 1.464 + return true; 1.465 + } 1.466 + /* add point to bounding circle center (for average calculation) */ 1.467 + cluster->bounding.center.lat += points[j].lat; 1.468 + cluster->bounding.center.lon += value; 1.469 + } 1.470 + /* count total number of points */ 1.471 + total_npoints += npoints; 1.472 + } 1.473 + /* determine average latitude and longitude of cluster */ 1.474 + cluster->bounding.center.lat /= total_npoints; 1.475 + cluster->bounding.center.lon /= total_npoints; 1.476 + /* normalize longitude of center of cluster bounding circle */ 1.477 + if (cluster->bounding.center.lon < -180) { 1.478 + cluster->bounding.center.lon += 360; 1.479 + } 1.480 + else if (cluster->bounding.center.lon > 180) { 1.481 + cluster->bounding.center.lon -= 360; 1.482 + } 1.483 + /* round bounding circle center (useful if it is used by other functions) */ 1.484 + cluster->bounding.center.lat = pgl_round(cluster->bounding.center.lat); 1.485 + cluster->bounding.center.lon = pgl_round(cluster->bounding.center.lon); 1.486 + /* calculate radius of bounding circle */ 1.487 + for (i=0; i<cluster->nentries; i++) { 1.488 + npoints = cluster->entries[i].npoints; 1.489 + points = PGL_ENTRY_POINTS(cluster, i); 1.490 + for (j=0; j<npoints; j++) { 1.491 + value = pgl_distance( 1.492 + cluster->bounding.center.lat, cluster->bounding.center.lon, 1.493 + points[j].lat, points[j].lon 1.494 + ); 1.495 + if (value > cluster->bounding.radius) cluster->bounding.radius = value; 1.496 + } 1.497 + } 1.498 + } 1.499 + /* return true (east/west orientation is unambiguous) */ 1.500 + return true; 1.501 +} 1.502 + 1.503 +/* check if point is inside cluster */ 1.504 +static bool pgl_point_in_cluster(pgl_point *point, pgl_cluster *cluster) { 1.505 + int i, j, k; /* i: entry, j: point in entry, k: next point in entry */ 1.506 + int entrytype; /* type of entry */ 1.507 + int npoints; /* number of points in entry */ 1.508 + pgl_point *points; /* array of points in entry */ 1.509 + int lon_dir = 0; /* first vertex west (-1) or east (+1) */ 1.510 + double lon_break = 0; /* antipodal longitude of first vertex */ 1.511 + double lat0 = point->lat; /* latitude of point */ 1.512 + double lon0; /* (adjusted) longitude of point */ 1.513 + double lat1, lon1; /* latitude and (adjusted) longitude of vertex */ 1.514 + double lat2, lon2; /* latitude and (adjusted) longitude of next vertex */ 1.515 + double lon; /* longitude of intersection */ 1.516 + int counter = 0; /* counter for intersections east of point */ 1.517 + /* points outside bounding circle are always assumed to be non-overlapping */ 1.518 + /* (necessary for consistent table and index scans) */ 1.519 + if ( 1.520 + pgl_distance( 1.521 + point->lat, point->lon, 1.522 + cluster->bounding.center.lat, cluster->bounding.center.lon 1.523 + ) > cluster->bounding.radius 1.524 + ) return false; 1.525 + /* iterate over all entries */ 1.526 + for (i=0; i<cluster->nentries; i++) { 1.527 + /* get properties of entry */ 1.528 + entrytype = cluster->entries[i].entrytype; 1.529 + npoints = cluster->entries[i].npoints; 1.530 + points = PGL_ENTRY_POINTS(cluster, i); 1.531 + /* determine east/west orientation of first point of entry and calculate 1.532 + antipodal longitude */ 1.533 + lon_break = points[0].lon; 1.534 + if (lon_break < 0) { lon_dir = -1; lon_break += 180; } 1.535 + else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; } 1.536 + else lon_dir = 0; 1.537 + /* get longitude of point */ 1.538 + lon0 = point->lon; 1.539 + /* consider longitude wrap-around for point */ 1.540 + if (lon_dir < 0 && lon0 > lon_break) lon0 = pgl_round(lon0 - 360); 1.541 + else if (lon_dir > 0 && lon0 < lon_break) lon0 = pgl_round(lon0 + 360); 1.542 + /* iterate over all edges and vertices */ 1.543 + for (j=0; j<npoints; j++) { 1.544 + /* return true if point is on vertex of polygon */ 1.545 + if (pgl_point_cmp(point, &(points[j])) == 0) return true; 1.546 + /* calculate index of next vertex */ 1.547 + k = (j+1) % npoints; 1.548 + /* skip last edge unless entry is (closed) outline or polygon */ 1.549 + if ( 1.550 + k == 0 && 1.551 + entrytype != PGL_ENTRY_OUTLINE && 1.552 + entrytype != PGL_ENTRY_POLYGON 1.553 + ) continue; 1.554 + /* get latitude and longitude values of edge */ 1.555 + lat1 = points[j].lat; 1.556 + lat2 = points[k].lat; 1.557 + lon1 = points[j].lon; 1.558 + lon2 = points[k].lon; 1.559 + /* consider longitude wrap-around for edge */ 1.560 + if (lon_dir < 0 && lon1 > lon_break) lon1 = pgl_round(lon1 - 360); 1.561 + else if (lon_dir > 0 && lon1 < lon_break) lon1 = pgl_round(lon1 + 360); 1.562 + if (lon_dir < 0 && lon2 > lon_break) lon2 = pgl_round(lon2 - 360); 1.563 + else if (lon_dir > 0 && lon2 < lon_break) lon2 = pgl_round(lon2 + 360); 1.564 + /* return true if point is on horizontal (west to east) edge of polygon */ 1.565 + if ( 1.566 + lat0 == lat1 && lat0 == lat2 && 1.567 + ( (lon0 >= lon1 && lon0 <= lon2) || (lon0 >= lon2 && lon0 <= lon1) ) 1.568 + ) return true; 1.569 + /* check if edge crosses east/west line of point */ 1.570 + if ((lat1 < lat0 && lat2 >= lat0) || (lat2 < lat0 && lat1 >= lat0)) { 1.571 + /* calculate longitude of intersection */ 1.572 + lon = (lon1 * (lat2-lat0) + lon2 * (lat0-lat1)) / (lat2-lat1); 1.573 + /* return true if intersection goes (approximately) through point */ 1.574 + if (pgl_round(lon) == lon0) return true; 1.575 + /* count intersection if east of point and entry is polygon*/ 1.576 + if (entrytype == PGL_ENTRY_POLYGON && lon > lon0) counter++; 1.577 + } 1.578 + } 1.579 + } 1.580 + /* return true if number of intersections is odd */ 1.581 + return counter & 1; 1.582 +} 1.583 + 1.584 +/* calculate (approximate) distance between point and cluster */ 1.585 +static double pgl_point_cluster_distance(pgl_point *point, pgl_cluster *cluster) { 1.586 + int i, j, k; /* i: entry, j: point in entry, k: next point in entry */ 1.587 + int entrytype; /* type of entry */ 1.588 + int npoints; /* number of points in entry */ 1.589 + pgl_point *points; /* array of points in entry */ 1.590 + int lon_dir = 0; /* first vertex west (-1) or east (+1) */ 1.591 + double lon_break = 0; /* antipodal longitude of first vertex */ 1.592 + double lon_min = 0; /* minimum (adjusted) longitude of entry vertices */ 1.593 + double lon_max = 0; /* maximum (adjusted) longitude of entry vertices */ 1.594 + double lat0 = point->lat; /* latitude of point */ 1.595 + double lon0; /* (adjusted) longitude of point */ 1.596 + double lat1, lon1; /* latitude and (adjusted) longitude of vertex */ 1.597 + double lat2, lon2; /* latitude and (adjusted) longitude of next vertex */ 1.598 + double s; /* scalar for vector calculations */ 1.599 + double dist; /* distance calculated in one step */ 1.600 + double min_dist = INFINITY; /* minimum distance */ 1.601 + /* distance is zero if point is contained in cluster */ 1.602 + if (pgl_point_in_cluster(point, cluster)) return 0; 1.603 + /* iterate over all entries */ 1.604 + for (i=0; i<cluster->nentries; i++) { 1.605 + /* get properties of entry */ 1.606 + entrytype = cluster->entries[i].entrytype; 1.607 + npoints = cluster->entries[i].npoints; 1.608 + points = PGL_ENTRY_POINTS(cluster, i); 1.609 + /* determine east/west orientation of first point of entry and calculate 1.610 + antipodal longitude */ 1.611 + lon_break = points[0].lon; 1.612 + if (lon_break < 0) { lon_dir = -1; lon_break += 180; } 1.613 + else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; } 1.614 + else lon_dir = 0; 1.615 + /* determine covered longitude range */ 1.616 + for (j=0; j<npoints; j++) { 1.617 + /* get longitude of vertex */ 1.618 + lon1 = points[j].lon; 1.619 + /* adjust longitude to fix potential wrap-around */ 1.620 + if (lon_dir < 0 && lon1 > lon_break) lon1 -= 360; 1.621 + else if (lon_dir > 0 && lon1 < lon_break) lon1 += 360; 1.622 + /* update minimum and maximum longitude of polygon */ 1.623 + if (j == 0 || lon1 < lon_min) lon_min = lon1; 1.624 + if (j == 0 || lon1 > lon_max) lon_max = lon1; 1.625 + } 1.626 + /* adjust longitude wrap-around according to full longitude range */ 1.627 + lon_break = (lon_max + lon_min) / 2; 1.628 + if (lon_break < 0) { lon_dir = -1; lon_break += 180; } 1.629 + else if (lon_break > 0) { lon_dir = 1; lon_break -= 180; } 1.630 + /* get longitude of point */ 1.631 + lon0 = point->lon; 1.632 + /* consider longitude wrap-around for point */ 1.633 + if (lon_dir < 0 && lon0 > lon_break) lon0 -= 360; 1.634 + else if (lon_dir > 0 && lon0 < lon_break) lon0 += 360; 1.635 + /* iterate over all edges and vertices */ 1.636 + for (j=0; j<npoints; j++) { 1.637 + /* get latitude and longitude values of current point */ 1.638 + lat1 = points[j].lat; 1.639 + lon1 = points[j].lon; 1.640 + /* consider longitude wrap-around for current point */ 1.641 + if (lon_dir < 0 && lon1 > lon_break) lon1 -= 360; 1.642 + else if (lon_dir > 0 && lon1 < lon_break) lon1 += 360; 1.643 + /* calculate distance to vertex */ 1.644 + dist = pgl_distance(lat0, lon0, lat1, lon1); 1.645 + /* store calculated distance if smallest */ 1.646 + if (dist < min_dist) min_dist = dist; 1.647 + /* calculate index of next vertex */ 1.648 + k = (j+1) % npoints; 1.649 + /* skip last edge unless entry is (closed) outline or polygon */ 1.650 + if ( 1.651 + k == 0 && 1.652 + entrytype != PGL_ENTRY_OUTLINE && 1.653 + entrytype != PGL_ENTRY_POLYGON 1.654 + ) continue; 1.655 + /* get latitude and longitude values of next point */ 1.656 + lat2 = points[k].lat; 1.657 + lon2 = points[k].lon; 1.658 + /* consider longitude wrap-around for next point */ 1.659 + if (lon_dir < 0 && lon2 > lon_break) lon2 -= 360; 1.660 + else if (lon_dir > 0 && lon2 < lon_break) lon2 += 360; 1.661 + /* go to next vertex and edge if edge is degenerated */ 1.662 + if (lat1 == lat2 && lon1 == lon2) continue; 1.663 + /* otherwise test if point can be projected onto edge of polygon */ 1.664 + s = ( 1.665 + ((lat0-lat1) * (lat2-lat1) + (lon0-lon1) * (lon2-lon1)) / 1.666 + ((lat2-lat1) * (lat2-lat1) + (lon2-lon1) * (lon2-lon1)) 1.667 + ); 1.668 + /* go to next vertex and edge if point cannot be projected */ 1.669 + if (!(s > 0 && s < 1)) continue; 1.670 + /* calculate distance from original point to projected point */ 1.671 + dist = pgl_distance( 1.672 + lat0, lon0, 1.673 + lat1 + s * (lat2-lat1), 1.674 + lon1 + s * (lon2-lon1) 1.675 + ); 1.676 + /* store calculated distance if smallest */ 1.677 + if (dist < min_dist) min_dist = dist; 1.678 + } 1.679 + } 1.680 + /* return minimum distance */ 1.681 + return min_dist; 1.682 +} 1.683 + 1.684 +/* estimator function for distance between box and point */ 1.685 +/* allowed to return smaller values than actually correct */ 1.686 +static double pgl_estimate_point_box_distance(pgl_point *point, pgl_box *box) { 1.687 + double dlon; /* longitude range of box (delta longitude) */ 1.688 + double h; /* half of distance along meridian */ 1.689 + double d; /* distance between both southern or both northern points */ 1.690 + double cur_dist; /* calculated distance */ 1.691 + double min_dist; /* minimum distance calculated */ 1.692 + /* return infinity if bounding box is empty */ 1.693 + if (box->lat_min > box->lat_max) return INFINITY; 1.694 + /* return zero if point is inside bounding box */ 1.695 + if (pgl_point_in_box(point, box)) return 0; 1.696 + /* calculate delta longitude */ 1.697 + dlon = box->lon_max - box->lon_min; 1.698 + if (dlon < 0) dlon += 360; /* 180th meridian crossed */ 1.699 + /* if delta longitude is greater than 180 degrees, perform safe fall-back */ 1.700 + if (dlon > 180) return 0; 1.701 + /* calculate half of distance along meridian */ 1.702 + h = pgl_distance(box->lat_min, 0, box->lat_max, 0) / 2; 1.703 + /* calculate full distance between southern points */ 1.704 + d = pgl_distance(box->lat_min, 0, box->lat_min, dlon); 1.705 + /* calculate maximum of full distance and half distance */ 1.706 + if (h > d) d = h; 1.707 + /* calculate distance from point to first southern vertex and substract 1.708 + maximum error */ 1.709 + min_dist = pgl_distance( 1.710 + point->lat, point->lon, box->lat_min, box->lon_min 1.711 + ) - d; 1.712 + /* return zero if estimated distance is smaller than zero */ 1.713 + if (min_dist <= 0) return 0; 1.714 + /* repeat procedure with second southern vertex */ 1.715 + cur_dist = pgl_distance( 1.716 + point->lat, point->lon, box->lat_min, box->lon_max 1.717 + ) - d; 1.718 + if (cur_dist <= 0) return 0; 1.719 + if (cur_dist < min_dist) min_dist = cur_dist; 1.720 + /* calculate full distance between northern points */ 1.721 + d = pgl_distance(box->lat_max, 0, box->lat_max, dlon); 1.722 + /* calculate maximum of full distance and half distance */ 1.723 + if (h > d) d = h; 1.724 + /* repeat procedure with northern vertices */ 1.725 + cur_dist = pgl_distance( 1.726 + point->lat, point->lon, box->lat_max, box->lon_max 1.727 + ) - d; 1.728 + if (cur_dist <= 0) return 0; 1.729 + if (cur_dist < min_dist) min_dist = cur_dist; 1.730 + cur_dist = pgl_distance( 1.731 + point->lat, point->lon, box->lat_max, box->lon_min 1.732 + ) - d; 1.733 + if (cur_dist <= 0) return 0; 1.734 + if (cur_dist < min_dist) min_dist = cur_dist; 1.735 + /* return smallest value (unless already returned zero) */ 1.736 + return min_dist; 1.737 +} 1.738 + 1.739 + 1.740 +/*----------------------------* 1.741 + * fractal geographic index * 1.742 + *----------------------------*/ 1.743 + 1.744 +/* number of bytes used for geographic (center) position in keys */ 1.745 +#define PGL_KEY_LATLON_BYTELEN 7 1.746 + 1.747 +/* maximum reference value for logarithmic size of geographic objects */ 1.748 +#define PGL_AREAKEY_REFOBJSIZE (PGL_DIAMETER/3.0) /* can be tweaked */ 1.749 + 1.750 +/* safety margin to avoid floating point errors in distance estimation */ 1.751 +#define PGL_FPE_SAFETY (1.0+1e-14) /* slightly greater than 1.0 */ 1.752 + 1.753 +/* pointer to index key (either pgl_pointkey or pgl_areakey) */ 1.754 +typedef unsigned char *pgl_keyptr; 1.755 + 1.756 +/* index key for points (objects with zero area) on the spheroid */ 1.757 +/* bit 0..55: interspersed bits of latitude and longitude, 1.758 + bit 56..57: always zero, 1.759 + bit 58..63: node depth in hypothetic (full) tree from 0 to 56 (incl.) */ 1.760 +typedef unsigned char pgl_pointkey[PGL_KEY_LATLON_BYTELEN+1]; 1.761 + 1.762 +/* index key for geographic objects on spheroid with area greater than zero */ 1.763 +/* bit 0..55: interspersed bits of latitude and longitude of center point, 1.764 + bit 56: always set to 1, 1.765 + bit 57..63: node depth in hypothetic (full) tree from 0 to (2*56)+1 (incl.), 1.766 + bit 64..71: logarithmic object size from 0 to 56+1 = 57 (incl.), but set to 1.767 + PGL_KEY_OBJSIZE_EMPTY (with interspersed bits = 0 and node depth 1.768 + = 113) for empty objects, and set to PGL_KEY_OBJSIZE_UNIVERSAL 1.769 + (with interspersed bits = 0 and node depth = 0) for keys which 1.770 + cover both empty and non-empty objects */ 1.771 + 1.772 +typedef unsigned char pgl_areakey[PGL_KEY_LATLON_BYTELEN+2]; 1.773 + 1.774 +/* helper macros for reading/writing index keys */ 1.775 +#define PGL_KEY_NODEDEPTH_OFFSET PGL_KEY_LATLON_BYTELEN 1.776 +#define PGL_KEY_OBJSIZE_OFFSET (PGL_KEY_NODEDEPTH_OFFSET+1) 1.777 +#define PGL_POINTKEY_MAXDEPTH (PGL_KEY_LATLON_BYTELEN*8) 1.778 +#define PGL_AREAKEY_MAXDEPTH (2*PGL_POINTKEY_MAXDEPTH+1) 1.779 +#define PGL_AREAKEY_MAXOBJSIZE (PGL_POINTKEY_MAXDEPTH+1) 1.780 +#define PGL_AREAKEY_TYPEMASK 0x80 1.781 +#define PGL_KEY_LATLONBIT(key, n) ((key)[(n)/8] & (0x80 >> ((n)%8))) 1.782 +#define PGL_KEY_LATLONBIT_DIFF(key1, key2, n) \ 1.783 + ( PGL_KEY_LATLONBIT(key1, n) ^ \ 1.784 + PGL_KEY_LATLONBIT(key2, n) ) 1.785 +#define PGL_KEY_IS_AREAKEY(key) ((key)[PGL_KEY_NODEDEPTH_OFFSET] & \ 1.786 + PGL_AREAKEY_TYPEMASK) 1.787 +#define PGL_KEY_NODEDEPTH(key) ((key)[PGL_KEY_NODEDEPTH_OFFSET] & \ 1.788 + (PGL_AREAKEY_TYPEMASK-1)) 1.789 +#define PGL_KEY_OBJSIZE(key) ((key)[PGL_KEY_OBJSIZE_OFFSET]) 1.790 +#define PGL_KEY_OBJSIZE_EMPTY 126 1.791 +#define PGL_KEY_OBJSIZE_UNIVERSAL 127 1.792 +#define PGL_KEY_IS_EMPTY(key) ( PGL_KEY_IS_AREAKEY(key) && \ 1.793 + (key)[PGL_KEY_OBJSIZE_OFFSET] == \ 1.794 + PGL_KEY_OBJSIZE_EMPTY ) 1.795 +#define PGL_KEY_IS_UNIVERSAL(key) ( PGL_KEY_IS_AREAKEY(key) && \ 1.796 + (key)[PGL_KEY_OBJSIZE_OFFSET] == \ 1.797 + PGL_KEY_OBJSIZE_UNIVERSAL ) 1.798 + 1.799 +/* set area key to match empty objects only */ 1.800 +static void pgl_key_set_empty(pgl_keyptr key) { 1.801 + memset(key, 0, sizeof(pgl_areakey)); 1.802 + /* Note: setting node depth to maximum is required for picksplit function */ 1.803 + key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | PGL_AREAKEY_MAXDEPTH; 1.804 + key[PGL_KEY_OBJSIZE_OFFSET] = PGL_KEY_OBJSIZE_EMPTY; 1.805 +} 1.806 + 1.807 +/* set area key to match any object (including empty objects) */ 1.808 +static void pgl_key_set_universal(pgl_keyptr key) { 1.809 + memset(key, 0, sizeof(pgl_areakey)); 1.810 + key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK; 1.811 + key[PGL_KEY_OBJSIZE_OFFSET] = PGL_KEY_OBJSIZE_UNIVERSAL; 1.812 +} 1.813 + 1.814 +/* convert a point on earth into a max-depth key to be used in index */ 1.815 +static void pgl_point_to_key(pgl_point *point, pgl_keyptr key) { 1.816 + double lat = point->lat; 1.817 + double lon = point->lon; 1.818 + int i; 1.819 + /* clear latitude and longitude bits */ 1.820 + memset(key, 0, PGL_KEY_LATLON_BYTELEN); 1.821 + /* set node depth to maximum and type bit to zero */ 1.822 + key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_POINTKEY_MAXDEPTH; 1.823 + /* iterate over all latitude/longitude bit pairs */ 1.824 + for (i=0; i<PGL_POINTKEY_MAXDEPTH/2; i++) { 1.825 + /* determine latitude bit */ 1.826 + if (lat >= 0) { 1.827 + key[i/4] |= 0x80 >> (2*(i%4)); 1.828 + lat *= 2; lat -= 90; 1.829 + } else { 1.830 + lat *= 2; lat += 90; 1.831 + } 1.832 + /* determine longitude bit */ 1.833 + if (lon >= 0) { 1.834 + key[i/4] |= 0x80 >> (2*(i%4)+1); 1.835 + lon *= 2; lon -= 180; 1.836 + } else { 1.837 + lon *= 2; lon += 180; 1.838 + } 1.839 + } 1.840 +} 1.841 + 1.842 +/* convert a circle on earth into a max-depth key to be used in an index */ 1.843 +static void pgl_circle_to_key(pgl_circle *circle, pgl_keyptr key) { 1.844 + /* handle special case of empty circle */ 1.845 + if (circle->radius < 0) { 1.846 + pgl_key_set_empty(key); 1.847 + return; 1.848 + } 1.849 + /* perform same action as for point keys */ 1.850 + pgl_point_to_key(&(circle->center), key); 1.851 + /* but overwrite type and node depth to fit area index key */ 1.852 + key[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | PGL_AREAKEY_MAXDEPTH; 1.853 + /* check if radius is greater than (or equal to) reference size */ 1.854 + /* (treat equal values as greater values for numerical safety) */ 1.855 + if (circle->radius >= PGL_AREAKEY_REFOBJSIZE) { 1.856 + /* if yes, set logarithmic size to zero */ 1.857 + key[PGL_KEY_OBJSIZE_OFFSET] = 0; 1.858 + } else { 1.859 + /* otherwise, determine logarithmic size iteratively */ 1.860 + /* (one step is equivalent to a factor of sqrt(2)) */ 1.861 + double reference = PGL_AREAKEY_REFOBJSIZE / M_SQRT2; 1.862 + int objsize = 1; 1.863 + while (objsize < PGL_AREAKEY_MAXOBJSIZE) { 1.864 + /* stop when radius is greater than (or equal to) adjusted reference */ 1.865 + /* (treat equal values as greater values for numerical safety) */ 1.866 + if (circle->radius >= reference) break; 1.867 + reference /= M_SQRT2; 1.868 + objsize++; 1.869 + } 1.870 + /* set logarithmic size to determined value */ 1.871 + key[PGL_KEY_OBJSIZE_OFFSET] = objsize; 1.872 + } 1.873 +} 1.874 + 1.875 +/* check if one key is subkey of another key or vice versa */ 1.876 +static bool pgl_keys_overlap(pgl_keyptr key1, pgl_keyptr key2) { 1.877 + int i; /* key bit offset (includes both lat/lon and log. obj. size bits) */ 1.878 + /* determine smallest depth */ 1.879 + int depth1 = PGL_KEY_NODEDEPTH(key1); 1.880 + int depth2 = PGL_KEY_NODEDEPTH(key2); 1.881 + int depth = (depth1 < depth2) ? depth1 : depth2; 1.882 + /* check if keys are area keys (assuming that both keys have same type) */ 1.883 + if (PGL_KEY_IS_AREAKEY(key1)) { 1.884 + int j = 0; /* bit offset for logarithmic object size bits */ 1.885 + int k = 0; /* bit offset for latitude and longitude */ 1.886 + /* fetch logarithmic object size information */ 1.887 + int objsize1 = PGL_KEY_OBJSIZE(key1); 1.888 + int objsize2 = PGL_KEY_OBJSIZE(key2); 1.889 + /* handle special cases for empty objects (universal and empty keys) */ 1.890 + if ( 1.891 + objsize1 == PGL_KEY_OBJSIZE_UNIVERSAL || 1.892 + objsize2 == PGL_KEY_OBJSIZE_UNIVERSAL 1.893 + ) return true; 1.894 + if ( 1.895 + objsize1 == PGL_KEY_OBJSIZE_EMPTY || 1.896 + objsize2 == PGL_KEY_OBJSIZE_EMPTY 1.897 + ) return objsize1 == objsize2; 1.898 + /* iterate through key bits */ 1.899 + for (i=0; i<depth; i++) { 1.900 + /* every second bit is a bit describing the object size */ 1.901 + if (i%2 == 0) { 1.902 + /* check if object size bit is different in both keys (objsize1 and 1.903 + objsize2 describe the minimum index when object size bit is set) */ 1.904 + if ( 1.905 + (objsize1 <= j && objsize2 > j) || 1.906 + (objsize2 <= j && objsize1 > j) 1.907 + ) { 1.908 + /* bit differs, therefore keys are in separate branches */ 1.909 + return false; 1.910 + } 1.911 + /* increase bit counter for object size bits */ 1.912 + j++; 1.913 + } 1.914 + /* all other bits describe latitude and longitude */ 1.915 + else { 1.916 + /* check if bit differs in both keys */ 1.917 + if (PGL_KEY_LATLONBIT_DIFF(key1, key2, k)) { 1.918 + /* bit differs, therefore keys are in separate branches */ 1.919 + return false; 1.920 + } 1.921 + /* increase bit counter for latitude/longitude bits */ 1.922 + k++; 1.923 + } 1.924 + } 1.925 + } 1.926 + /* if not, keys are point keys */ 1.927 + else { 1.928 + /* iterate through key bits */ 1.929 + for (i=0; i<depth; i++) { 1.930 + /* check if bit differs in both keys */ 1.931 + if (PGL_KEY_LATLONBIT_DIFF(key1, key2, i)) { 1.932 + /* bit differs, therefore keys are in separate branches */ 1.933 + return false; 1.934 + } 1.935 + } 1.936 + } 1.937 + /* return true because keys are in the same branch */ 1.938 + return true; 1.939 +} 1.940 + 1.941 +/* combine two keys into new key which covers both original keys */ 1.942 +/* (result stored in first argument) */ 1.943 +static void pgl_unite_keys(pgl_keyptr dst, pgl_keyptr src) { 1.944 + int i; /* key bit offset (includes both lat/lon and log. obj. size bits) */ 1.945 + /* determine smallest depth */ 1.946 + int depth1 = PGL_KEY_NODEDEPTH(dst); 1.947 + int depth2 = PGL_KEY_NODEDEPTH(src); 1.948 + int depth = (depth1 < depth2) ? depth1 : depth2; 1.949 + /* check if keys are area keys (assuming that both keys have same type) */ 1.950 + if (PGL_KEY_IS_AREAKEY(dst)) { 1.951 + pgl_areakey dstbuf = { 0, }; /* destination buffer (cleared) */ 1.952 + int j = 0; /* bit offset for logarithmic object size bits */ 1.953 + int k = 0; /* bit offset for latitude and longitude */ 1.954 + /* fetch logarithmic object size information */ 1.955 + int objsize1 = PGL_KEY_OBJSIZE(dst); 1.956 + int objsize2 = PGL_KEY_OBJSIZE(src); 1.957 + /* handle special cases for empty objects (universal and empty keys) */ 1.958 + if ( 1.959 + objsize1 > PGL_AREAKEY_MAXOBJSIZE || 1.960 + objsize2 > PGL_AREAKEY_MAXOBJSIZE 1.961 + ) { 1.962 + if ( 1.963 + objsize1 == PGL_KEY_OBJSIZE_EMPTY && 1.964 + objsize2 == PGL_KEY_OBJSIZE_EMPTY 1.965 + ) pgl_key_set_empty(dst); 1.966 + else pgl_key_set_universal(dst); 1.967 + return; 1.968 + } 1.969 + /* iterate through key bits */ 1.970 + for (i=0; i<depth; i++) { 1.971 + /* every second bit is a bit describing the object size */ 1.972 + if (i%2 == 0) { 1.973 + /* increase bit counter for object size bits first */ 1.974 + /* (handy when setting objsize variable) */ 1.975 + j++; 1.976 + /* check if object size bit is set in neither key */ 1.977 + if (objsize1 >= j && objsize2 >= j) { 1.978 + /* set objsize in destination buffer to indicate that size bit is 1.979 + unset in destination buffer at the current bit position */ 1.980 + dstbuf[PGL_KEY_OBJSIZE_OFFSET] = j; 1.981 + } 1.982 + /* break if object size bit is set in one key only */ 1.983 + else if (objsize1 >= j || objsize2 >= j) break; 1.984 + } 1.985 + /* all other bits describe latitude and longitude */ 1.986 + else { 1.987 + /* break if bit differs in both keys */ 1.988 + if (PGL_KEY_LATLONBIT(dst, k)) { 1.989 + if (!PGL_KEY_LATLONBIT(src, k)) break; 1.990 + /* but set bit in destination buffer if bit is set in both keys */ 1.991 + dstbuf[k/8] |= 0x80 >> (k%8); 1.992 + } else if (PGL_KEY_LATLONBIT(src, k)) break; 1.993 + /* increase bit counter for latitude/longitude bits */ 1.994 + k++; 1.995 + } 1.996 + } 1.997 + /* set common node depth and type bit (type bit = 1) */ 1.998 + dstbuf[PGL_KEY_NODEDEPTH_OFFSET] = PGL_AREAKEY_TYPEMASK | i; 1.999 + /* copy contents of destination buffer to first key */ 1.1000 + memcpy(dst, dstbuf, sizeof(pgl_areakey)); 1.1001 + } 1.1002 + /* if not, keys are point keys */ 1.1003 + else { 1.1004 + pgl_pointkey dstbuf = { 0, }; /* destination buffer (cleared) */ 1.1005 + /* iterate through key bits */ 1.1006 + for (i=0; i<depth; i++) { 1.1007 + /* break if bit differs in both keys */ 1.1008 + if (PGL_KEY_LATLONBIT(dst, i)) { 1.1009 + if (!PGL_KEY_LATLONBIT(src, i)) break; 1.1010 + /* but set bit in destination buffer if bit is set in both keys */ 1.1011 + dstbuf[i/8] |= 0x80 >> (i%8); 1.1012 + } else if (PGL_KEY_LATLONBIT(src, i)) break; 1.1013 + } 1.1014 + /* set common node depth (type bit = 0) */ 1.1015 + dstbuf[PGL_KEY_NODEDEPTH_OFFSET] = i; 1.1016 + /* copy contents of destination buffer to first key */ 1.1017 + memcpy(dst, dstbuf, sizeof(pgl_pointkey)); 1.1018 + } 1.1019 +} 1.1020 + 1.1021 +/* determine center(!) boundaries and radius estimation of index key */ 1.1022 +static double pgl_key_to_box(pgl_keyptr key, pgl_box *box) { 1.1023 + int i; 1.1024 + /* determine node depth */ 1.1025 + int depth = PGL_KEY_NODEDEPTH(key); 1.1026 + /* center point of possible result */ 1.1027 + double lat = 0; 1.1028 + double lon = 0; 1.1029 + /* maximum distance of real center point from key center */ 1.1030 + double dlat = 90; 1.1031 + double dlon = 180; 1.1032 + /* maximum radius of contained objects */ 1.1033 + double radius = 0; /* always return zero for point index keys */ 1.1034 + /* check if key is area key */ 1.1035 + if (PGL_KEY_IS_AREAKEY(key)) { 1.1036 + /* get logarithmic object size */ 1.1037 + int objsize = PGL_KEY_OBJSIZE(key); 1.1038 + /* handle special cases for empty objects (universal and empty keys) */ 1.1039 + if (objsize == PGL_KEY_OBJSIZE_EMPTY) { 1.1040 + pgl_box_set_empty(box); 1.1041 + return 0; 1.1042 + } else if (objsize == PGL_KEY_OBJSIZE_UNIVERSAL) { 1.1043 + box->lat_min = -90; 1.1044 + box->lat_max = 90; 1.1045 + box->lon_min = -180; 1.1046 + box->lon_max = 180; 1.1047 + return 0; /* any value >= 0 would do */ 1.1048 + } 1.1049 + /* calculate maximum possible radius of objects covered by the given key */ 1.1050 + if (objsize == 0) radius = INFINITY; 1.1051 + else { 1.1052 + radius = PGL_AREAKEY_REFOBJSIZE; 1.1053 + while (--objsize) radius /= M_SQRT2; 1.1054 + } 1.1055 + /* iterate over latitude and longitude bits in key */ 1.1056 + /* (every second bit is a latitude or longitude bit) */ 1.1057 + for (i=0; i<depth/2; i++) { 1.1058 + /* check if latitude bit */ 1.1059 + if (i%2 == 0) { 1.1060 + /* cut latitude dimension in half */ 1.1061 + dlat /= 2; 1.1062 + /* increase center latitude if bit is 1, otherwise decrease */ 1.1063 + if (PGL_KEY_LATLONBIT(key, i)) lat += dlat; 1.1064 + else lat -= dlat; 1.1065 + } 1.1066 + /* otherwise longitude bit */ 1.1067 + else { 1.1068 + /* cut longitude dimension in half */ 1.1069 + dlon /= 2; 1.1070 + /* increase center longitude if bit is 1, otherwise decrease */ 1.1071 + if (PGL_KEY_LATLONBIT(key, i)) lon += dlon; 1.1072 + else lon -= dlon; 1.1073 + } 1.1074 + } 1.1075 + } 1.1076 + /* if not, keys are point keys */ 1.1077 + else { 1.1078 + /* iterate over all bits in key */ 1.1079 + for (i=0; i<depth; i++) { 1.1080 + /* check if latitude bit */ 1.1081 + if (i%2 == 0) { 1.1082 + /* cut latitude dimension in half */ 1.1083 + dlat /= 2; 1.1084 + /* increase center latitude if bit is 1, otherwise decrease */ 1.1085 + if (PGL_KEY_LATLONBIT(key, i)) lat += dlat; 1.1086 + else lat -= dlat; 1.1087 + } 1.1088 + /* otherwise longitude bit */ 1.1089 + else { 1.1090 + /* cut longitude dimension in half */ 1.1091 + dlon /= 2; 1.1092 + /* increase center longitude if bit is 1, otherwise decrease */ 1.1093 + if (PGL_KEY_LATLONBIT(key, i)) lon += dlon; 1.1094 + else lon -= dlon; 1.1095 + } 1.1096 + } 1.1097 + } 1.1098 + /* calculate boundaries from center point and remaining dlat and dlon */ 1.1099 + /* (return values through pointer to box) */ 1.1100 + box->lat_min = lat - dlat; 1.1101 + box->lat_max = lat + dlat; 1.1102 + box->lon_min = lon - dlon; 1.1103 + box->lon_max = lon + dlon; 1.1104 + /* return radius (as a function return value) */ 1.1105 + return radius; 1.1106 +} 1.1107 + 1.1108 +/* estimator function for distance between point and index key */ 1.1109 +/* allowed to return smaller values than actually correct */ 1.1110 +static double pgl_estimate_key_distance(pgl_keyptr key, pgl_point *point) { 1.1111 + pgl_box box; /* center(!) bounding box of area index key */ 1.1112 + /* calculate center(!) bounding box and maximum radius of objects covered 1.1113 + by area index key (radius is zero for point index keys) */ 1.1114 + double distance = pgl_key_to_box(key, &box); 1.1115 + /* calculate estimated distance between bounding box of center point of 1.1116 + indexed object and point passed as second argument, then substract maximum 1.1117 + radius of objects covered by index key */ 1.1118 + /* (use PGL_FPE_SAFETY factor to cope with minor floating point errors) */ 1.1119 + distance = ( 1.1120 + pgl_estimate_point_box_distance(point, &box) / PGL_FPE_SAFETY - 1.1121 + distance * PGL_FPE_SAFETY 1.1122 + ); 1.1123 + /* truncate negative results to zero */ 1.1124 + if (distance <= 0) distance = 0; 1.1125 + /* return result */ 1.1126 + return distance; 1.1127 +} 1.1128 + 1.1129 + 1.1130 +/*---------------------------------* 1.1131 + * helper functions for text I/O * 1.1132 + *---------------------------------*/ 1.1133 + 1.1134 +#define PGL_NUMBUFLEN 64 /* buffer size for number to string conversion */ 1.1135 + 1.1136 +/* convert floating point number to string (round-trip safe) */ 1.1137 +static void pgl_print_float(char *buf, double flt) { 1.1138 + /* check if number is integral */ 1.1139 + if (trunc(flt) == flt) { 1.1140 + /* for integral floats use maximum precision */ 1.1141 + snprintf(buf, PGL_NUMBUFLEN, "%.17g", flt); 1.1142 + } else { 1.1143 + /* otherwise check if 15, 16, or 17 digits needed (round-trip safety) */ 1.1144 + snprintf(buf, PGL_NUMBUFLEN, "%.15g", flt); 1.1145 + if (strtod(buf, NULL) != flt) snprintf(buf, PGL_NUMBUFLEN, "%.16g", flt); 1.1146 + if (strtod(buf, NULL) != flt) snprintf(buf, PGL_NUMBUFLEN, "%.17g", flt); 1.1147 + } 1.1148 +} 1.1149 + 1.1150 +/* convert latitude floating point number (in degrees) to string */ 1.1151 +static void pgl_print_lat(char *buf, double lat) { 1.1152 + if (signbit(lat)) { 1.1153 + /* treat negative latitudes (including -0) as south */ 1.1154 + snprintf(buf, PGL_NUMBUFLEN, "S%015.12f", -lat); 1.1155 + } else { 1.1156 + /* treat positive latitudes (including +0) as north */ 1.1157 + snprintf(buf, PGL_NUMBUFLEN, "N%015.12f", lat); 1.1158 + } 1.1159 +} 1.1160 + 1.1161 +/* convert longitude floating point number (in degrees) to string */ 1.1162 +static void pgl_print_lon(char *buf, double lon) { 1.1163 + if (signbit(lon)) { 1.1164 + /* treat negative longitudes (including -0) as west */ 1.1165 + snprintf(buf, PGL_NUMBUFLEN, "W%016.12f", -lon); 1.1166 + } else { 1.1167 + /* treat positive longitudes (including +0) as east */ 1.1168 + snprintf(buf, PGL_NUMBUFLEN, "E%016.12f", lon); 1.1169 + } 1.1170 +} 1.1171 + 1.1172 +/* bit masks used as return value of pgl_scan() function */ 1.1173 +#define PGL_SCAN_NONE 0 /* no value has been parsed */ 1.1174 +#define PGL_SCAN_LAT (1<<0) /* latitude has been parsed */ 1.1175 +#define PGL_SCAN_LON (1<<1) /* longitude has been parsed */ 1.1176 +#define PGL_SCAN_LATLON (PGL_SCAN_LAT | PGL_SCAN_LON) /* bitwise OR of both */ 1.1177 + 1.1178 +/* parse a coordinate (can be latitude or longitude) */ 1.1179 +static int pgl_scan(char **str, double *lat, double *lon) { 1.1180 + double val; 1.1181 + int len; 1.1182 + if ( 1.1183 + sscanf(*str, " N %lf %n", &val, &len) || 1.1184 + sscanf(*str, " n %lf %n", &val, &len) 1.1185 + ) { 1.1186 + *str += len; *lat = val; return PGL_SCAN_LAT; 1.1187 + } 1.1188 + if ( 1.1189 + sscanf(*str, " S %lf %n", &val, &len) || 1.1190 + sscanf(*str, " s %lf %n", &val, &len) 1.1191 + ) { 1.1192 + *str += len; *lat = -val; return PGL_SCAN_LAT; 1.1193 + } 1.1194 + if ( 1.1195 + sscanf(*str, " E %lf %n", &val, &len) || 1.1196 + sscanf(*str, " e %lf %n", &val, &len) 1.1197 + ) { 1.1198 + *str += len; *lon = val; return PGL_SCAN_LON; 1.1199 + } 1.1200 + if ( 1.1201 + sscanf(*str, " W %lf %n", &val, &len) || 1.1202 + sscanf(*str, " w %lf %n", &val, &len) 1.1203 + ) { 1.1204 + *str += len; *lon = -val; return PGL_SCAN_LON; 1.1205 + } 1.1206 + return PGL_SCAN_NONE; 1.1207 +} 1.1208 + 1.1209 + 1.1210 +/*-----------------* 1.1211 + * SQL functions * 1.1212 + *-----------------*/ 1.1213 + 1.1214 +/* Note: These function names use "epoint", "ebox", etc. notation here instead 1.1215 + of "point", "box", etc. in order to distinguish them from any previously 1.1216 + defined functions. */ 1.1217 + 1.1218 +/* function needed for dummy types and/or not implemented features */ 1.1219 +PG_FUNCTION_INFO_V1(pgl_notimpl); 1.1220 +Datum pgl_notimpl(PG_FUNCTION_ARGS) { 1.1221 + ereport(ERROR, (errmsg("not implemented by pgLatLon"))); 1.1222 +} 1.1223 + 1.1224 +/* set point to latitude and longitude (including checks) */ 1.1225 +static void pgl_epoint_set_latlon(pgl_point *point, double lat, double lon) { 1.1226 + /* reject infinite or NaN values */ 1.1227 + if (!isfinite(lat) || !isfinite(lon)) { 1.1228 + ereport(ERROR, ( 1.1229 + errcode(ERRCODE_DATA_EXCEPTION), 1.1230 + errmsg("epoint requires finite coordinates") 1.1231 + )); 1.1232 + } 1.1233 + /* check latitude bounds */ 1.1234 + if (lat < -90) { 1.1235 + ereport(WARNING, (errmsg("latitude exceeds south pole"))); 1.1236 + lat = -90; 1.1237 + } else if (lat > 90) { 1.1238 + ereport(WARNING, (errmsg("latitude exceeds north pole"))); 1.1239 + lat = 90; 1.1240 + } 1.1241 + /* check longitude bounds */ 1.1242 + if (lon < -180) { 1.1243 + ereport(NOTICE, (errmsg("longitude west of 180th meridian normalized"))); 1.1244 + lon += 360 - trunc(lon / 360) * 360; 1.1245 + } else if (lon > 180) { 1.1246 + ereport(NOTICE, (errmsg("longitude east of 180th meridian normalized"))); 1.1247 + lon -= 360 + trunc(lon / 360) * 360; 1.1248 + } 1.1249 + /* store rounded latitude/longitude values for round-trip safety */ 1.1250 + point->lat = pgl_round(lat); 1.1251 + point->lon = pgl_round(lon); 1.1252 +} 1.1253 + 1.1254 +/* create point ("epoint" in SQL) from latitude and longitude */ 1.1255 +PG_FUNCTION_INFO_V1(pgl_create_epoint); 1.1256 +Datum pgl_create_epoint(PG_FUNCTION_ARGS) { 1.1257 + pgl_point *point = (pgl_point *)palloc(sizeof(pgl_point)); 1.1258 + pgl_epoint_set_latlon(point, PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1)); 1.1259 + PG_RETURN_POINTER(point); 1.1260 +} 1.1261 + 1.1262 +/* parse point ("epoint" in SQL) */ 1.1263 +/* format: '[NS]<float> [EW]<float>' */ 1.1264 +PG_FUNCTION_INFO_V1(pgl_epoint_in); 1.1265 +Datum pgl_epoint_in(PG_FUNCTION_ARGS) { 1.1266 + char *str = PG_GETARG_CSTRING(0); /* input string */ 1.1267 + char *strptr = str; /* current position within string */ 1.1268 + int done = 0; /* bit mask storing if latitude or longitude was read */ 1.1269 + double lat, lon; /* parsed values as double precision floats */ 1.1270 + pgl_point *point; /* return value (to be palloc'ed) */ 1.1271 + /* parse two floats (each latitude or longitude) separated by white-space */ 1.1272 + done |= pgl_scan(&strptr, &lat, &lon); 1.1273 + if (strptr != str && isspace(strptr[-1])) { 1.1274 + done |= pgl_scan(&strptr, &lat, &lon); 1.1275 + } 1.1276 + /* require end of string, and latitude and longitude parsed successfully */ 1.1277 + if (strptr[0] || done != PGL_SCAN_LATLON) { 1.1278 + ereport(ERROR, ( 1.1279 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1280 + errmsg("invalid input syntax for type epoint: \"%s\"", str) 1.1281 + )); 1.1282 + } 1.1283 + /* allocate memory for result */ 1.1284 + point = (pgl_point *)palloc(sizeof(pgl_point)); 1.1285 + /* set latitude and longitude (and perform checks) */ 1.1286 + pgl_epoint_set_latlon(point, lat, lon); 1.1287 + /* return result */ 1.1288 + PG_RETURN_POINTER(point); 1.1289 +} 1.1290 + 1.1291 +/* create box ("ebox" in SQL) that is empty */ 1.1292 +PG_FUNCTION_INFO_V1(pgl_create_empty_ebox); 1.1293 +Datum pgl_create_empty_ebox(PG_FUNCTION_ARGS) { 1.1294 + pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1295 + pgl_box_set_empty(box); 1.1296 + PG_RETURN_POINTER(box); 1.1297 +} 1.1298 + 1.1299 +/* set box to given boundaries (including checks) */ 1.1300 +static void pgl_ebox_set_boundaries( 1.1301 + pgl_box *box, 1.1302 + double lat_min, double lat_max, double lon_min, double lon_max 1.1303 +) { 1.1304 + /* if minimum latitude is greater than maximum latitude, return empty box */ 1.1305 + if (lat_min > lat_max) { 1.1306 + pgl_box_set_empty(box); 1.1307 + return; 1.1308 + } 1.1309 + /* otherwise reject infinite or NaN values */ 1.1310 + if ( 1.1311 + !isfinite(lat_min) || !isfinite(lat_max) || 1.1312 + !isfinite(lon_min) || !isfinite(lon_max) 1.1313 + ) { 1.1314 + ereport(ERROR, ( 1.1315 + errcode(ERRCODE_DATA_EXCEPTION), 1.1316 + errmsg("ebox requires finite coordinates") 1.1317 + )); 1.1318 + } 1.1319 + /* check latitude bounds */ 1.1320 + if (lat_max < -90) { 1.1321 + ereport(WARNING, (errmsg("northern latitude exceeds south pole"))); 1.1322 + lat_max = -90; 1.1323 + } else if (lat_max > 90) { 1.1324 + ereport(WARNING, (errmsg("northern latitude exceeds north pole"))); 1.1325 + lat_max = 90; 1.1326 + } 1.1327 + if (lat_min < -90) { 1.1328 + ereport(WARNING, (errmsg("southern latitude exceeds south pole"))); 1.1329 + lat_min = -90; 1.1330 + } else if (lat_min > 90) { 1.1331 + ereport(WARNING, (errmsg("southern latitude exceeds north pole"))); 1.1332 + lat_min = 90; 1.1333 + } 1.1334 + /* check if all longitudes are included */ 1.1335 + if (lon_max - lon_min >= 360) { 1.1336 + if (lon_max - lon_min > 360) ereport(WARNING, ( 1.1337 + errmsg("longitude coverage greater than 360 degrees") 1.1338 + )); 1.1339 + lon_min = -180; 1.1340 + lon_max = 180; 1.1341 + } else { 1.1342 + /* normalize longitude bounds */ 1.1343 + if (lon_min < -180) lon_min += 360 - trunc(lon_min / 360) * 360; 1.1344 + else if (lon_min > 180) lon_min -= 360 + trunc(lon_min / 360) * 360; 1.1345 + if (lon_max < -180) lon_max += 360 - trunc(lon_max / 360) * 360; 1.1346 + else if (lon_max > 180) lon_max -= 360 + trunc(lon_max / 360) * 360; 1.1347 + } 1.1348 + /* store rounded latitude/longitude values for round-trip safety */ 1.1349 + box->lat_min = pgl_round(lat_min); 1.1350 + box->lat_max = pgl_round(lat_max); 1.1351 + box->lon_min = pgl_round(lon_min); 1.1352 + box->lon_max = pgl_round(lon_max); 1.1353 + /* ensure that rounding does not change orientation */ 1.1354 + if (lon_min > lon_max && box->lon_min == box->lon_max) { 1.1355 + box->lon_min = -180; 1.1356 + box->lon_max = 180; 1.1357 + } 1.1358 +} 1.1359 + 1.1360 +/* create box ("ebox" in SQL) from min/max latitude and min/max longitude */ 1.1361 +PG_FUNCTION_INFO_V1(pgl_create_ebox); 1.1362 +Datum pgl_create_ebox(PG_FUNCTION_ARGS) { 1.1363 + pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1364 + pgl_ebox_set_boundaries( 1.1365 + box, 1.1366 + PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1), 1.1367 + PG_GETARG_FLOAT8(2), PG_GETARG_FLOAT8(3) 1.1368 + ); 1.1369 + PG_RETURN_POINTER(box); 1.1370 +} 1.1371 + 1.1372 +/* create box ("ebox" in SQL) from two points ("epoint"s) */ 1.1373 +/* (can not be used to cover a longitude range of more than 120 degrees) */ 1.1374 +PG_FUNCTION_INFO_V1(pgl_create_ebox_from_epoints); 1.1375 +Datum pgl_create_ebox_from_epoints(PG_FUNCTION_ARGS) { 1.1376 + pgl_point *point1 = (pgl_point *)PG_GETARG_POINTER(0); 1.1377 + pgl_point *point2 = (pgl_point *)PG_GETARG_POINTER(1); 1.1378 + pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1379 + double lat_min, lat_max, lon_min, lon_max; 1.1380 + double dlon; /* longitude range (delta longitude) */ 1.1381 + /* order latitude and longitude boundaries */ 1.1382 + if (point2->lat < point1->lat) { 1.1383 + lat_min = point2->lat; 1.1384 + lat_max = point1->lat; 1.1385 + } else { 1.1386 + lat_min = point1->lat; 1.1387 + lat_max = point2->lat; 1.1388 + } 1.1389 + if (point2->lon < point1->lon) { 1.1390 + lon_min = point2->lon; 1.1391 + lon_max = point1->lon; 1.1392 + } else { 1.1393 + lon_min = point1->lon; 1.1394 + lon_max = point2->lon; 1.1395 + } 1.1396 + /* calculate longitude range (round to avoid floating point errors) */ 1.1397 + dlon = pgl_round(lon_max - lon_min); 1.1398 + /* determine east-west direction */ 1.1399 + if (dlon >= 240) { 1.1400 + /* assume that 180th meridian is crossed and swap min/max longitude */ 1.1401 + double swap = lon_min; lon_min = lon_max; lon_max = swap; 1.1402 + } else if (dlon > 120) { 1.1403 + /* unclear orientation since delta longitude > 120 */ 1.1404 + ereport(ERROR, ( 1.1405 + errcode(ERRCODE_DATA_EXCEPTION), 1.1406 + errmsg("can not determine east/west orientation for ebox") 1.1407 + )); 1.1408 + } 1.1409 + /* use boundaries to setup box (and perform checks) */ 1.1410 + pgl_ebox_set_boundaries(box, lat_min, lat_max, lon_min, lon_max); 1.1411 + /* return result */ 1.1412 + PG_RETURN_POINTER(box); 1.1413 +} 1.1414 + 1.1415 +/* parse box ("ebox" in SQL) */ 1.1416 +/* format: '[NS]<float> [EW]<float> [NS]<float> [EW]<float>' 1.1417 + or: '[NS]<float> [NS]<float> [EW]<float> [EW]<float>' */ 1.1418 +PG_FUNCTION_INFO_V1(pgl_ebox_in); 1.1419 +Datum pgl_ebox_in(PG_FUNCTION_ARGS) { 1.1420 + char *str = PG_GETARG_CSTRING(0); /* input string */ 1.1421 + char *str_lower; /* lower case version of input string */ 1.1422 + char *strptr; /* current position within string */ 1.1423 + int valid; /* number of valid chars */ 1.1424 + int done; /* specifies if latitude or longitude was read */ 1.1425 + double val; /* temporary variable */ 1.1426 + int lat_count = 0; /* count of latitude values parsed */ 1.1427 + int lon_count = 0; /* count of longitufde values parsed */ 1.1428 + double lat_min, lat_max, lon_min, lon_max; /* see pgl_box struct */ 1.1429 + pgl_box *box; /* return value (to be palloc'ed) */ 1.1430 + /* lowercase input */ 1.1431 + str_lower = psprintf("%s", str); 1.1432 + for (strptr=str_lower; *strptr; strptr++) { 1.1433 + if (*strptr >= 'A' && *strptr <= 'Z') *strptr += 'a' - 'A'; 1.1434 + } 1.1435 + /* reset reading position to start of (lowercase) string */ 1.1436 + strptr = str_lower; 1.1437 + /* check if empty box */ 1.1438 + valid = 0; 1.1439 + sscanf(strptr, " empty %n", &valid); 1.1440 + if (valid && strptr[valid] == 0) { 1.1441 + /* allocate and return empty box */ 1.1442 + box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1443 + pgl_box_set_empty(box); 1.1444 + PG_RETURN_POINTER(box); 1.1445 + } 1.1446 + /* demand four blocks separated by whitespace */ 1.1447 + valid = 0; 1.1448 + sscanf(strptr, " %*s %*s %*s %*s %n", &valid); 1.1449 + /* if four blocks separated by whitespace exist, parse those blocks */ 1.1450 + if (strptr[valid] == 0) while (strptr[0]) { 1.1451 + /* parse either latitude or longitude (whichever found in input string) */ 1.1452 + done = pgl_scan(&strptr, &val, &val); 1.1453 + /* store latitude or longitude in lat_min, lat_max, lon_min, or lon_max */ 1.1454 + if (done == PGL_SCAN_LAT) { 1.1455 + if (!lat_count) lat_min = val; else lat_max = val; 1.1456 + lat_count++; 1.1457 + } else if (done == PGL_SCAN_LON) { 1.1458 + if (!lon_count) lon_min = val; else lon_max = val; 1.1459 + lon_count++; 1.1460 + } else { 1.1461 + break; 1.1462 + } 1.1463 + } 1.1464 + /* require end of string, and two latitude and two longitude values */ 1.1465 + if (strptr[0] || lat_count != 2 || lon_count != 2) { 1.1466 + ereport(ERROR, ( 1.1467 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1468 + errmsg("invalid input syntax for type ebox: \"%s\"", str) 1.1469 + )); 1.1470 + } 1.1471 + /* free lower case string */ 1.1472 + pfree(str_lower); 1.1473 + /* order boundaries (maximum greater than minimum) */ 1.1474 + if (lat_min > lat_max) { val = lat_min; lat_min = lat_max; lat_max = val; } 1.1475 + if (lon_min > lon_max) { val = lon_min; lon_min = lon_max; lon_max = val; } 1.1476 + /* allocate memory for result */ 1.1477 + box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1478 + /* set boundaries (and perform checks) */ 1.1479 + pgl_ebox_set_boundaries(box, lat_min, lat_max, lon_min, lon_max); 1.1480 + /* return result */ 1.1481 + PG_RETURN_POINTER(box); 1.1482 +} 1.1483 + 1.1484 +/* set circle to given latitude, longitude, and radius (including checks) */ 1.1485 +static void pgl_ecircle_set_latlon_radius( 1.1486 + pgl_circle *circle, double lat, double lon, double radius 1.1487 +) { 1.1488 + /* set center point (including checks) */ 1.1489 + pgl_epoint_set_latlon(&(circle->center), lat, lon); 1.1490 + /* handle non-positive radius */ 1.1491 + if (isnan(radius)) { 1.1492 + ereport(ERROR, ( 1.1493 + errcode(ERRCODE_DATA_EXCEPTION), 1.1494 + errmsg("invalid radius for ecircle") 1.1495 + )); 1.1496 + } 1.1497 + if (radius == 0) radius = 0; /* avoids -0 */ 1.1498 + else if (radius < 0) { 1.1499 + if (isfinite(radius)) { 1.1500 + ereport(NOTICE, (errmsg("negative radius converted to minus infinity"))); 1.1501 + } 1.1502 + radius = -INFINITY; 1.1503 + } 1.1504 + /* store radius (round-trip safety is ensured by pgl_print_float) */ 1.1505 + circle->radius = radius; 1.1506 +} 1.1507 + 1.1508 +/* create circle ("ecircle" in SQL) from latitude, longitude, and radius */ 1.1509 +PG_FUNCTION_INFO_V1(pgl_create_ecircle); 1.1510 +Datum pgl_create_ecircle(PG_FUNCTION_ARGS) { 1.1511 + pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle)); 1.1512 + pgl_ecircle_set_latlon_radius( 1.1513 + circle, PG_GETARG_FLOAT8(0), PG_GETARG_FLOAT8(1), PG_GETARG_FLOAT8(2) 1.1514 + ); 1.1515 + PG_RETURN_POINTER(circle); 1.1516 +} 1.1517 + 1.1518 +/* create circle ("ecircle" in SQL) from point ("epoint"), and radius */ 1.1519 +PG_FUNCTION_INFO_V1(pgl_create_ecircle_from_epoint); 1.1520 +Datum pgl_create_ecircle_from_epoint(PG_FUNCTION_ARGS) { 1.1521 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1522 + double radius = PG_GETARG_FLOAT8(1); 1.1523 + pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle)); 1.1524 + /* set latitude, longitude, radius (and perform checks) */ 1.1525 + pgl_ecircle_set_latlon_radius(circle, point->lat, point->lon, radius); 1.1526 + /* return result */ 1.1527 + PG_RETURN_POINTER(circle); 1.1528 +} 1.1529 + 1.1530 +/* parse circle ("ecircle" in SQL) */ 1.1531 +/* format: '[NS]<float> [EW]<float> <float>' */ 1.1532 +PG_FUNCTION_INFO_V1(pgl_ecircle_in); 1.1533 +Datum pgl_ecircle_in(PG_FUNCTION_ARGS) { 1.1534 + char *str = PG_GETARG_CSTRING(0); /* input string */ 1.1535 + char *strptr = str; /* current position within string */ 1.1536 + double lat, lon, radius; /* parsed values as double precision flaots */ 1.1537 + int valid = 0; /* number of valid chars */ 1.1538 + int done = 0; /* stores if latitude and/or longitude was read */ 1.1539 + pgl_circle *circle; /* return value (to be palloc'ed) */ 1.1540 + /* demand three blocks separated by whitespace */ 1.1541 + sscanf(strptr, " %*s %*s %*s %n", &valid); 1.1542 + /* if three blocks separated by whitespace exist, parse those blocks */ 1.1543 + if (strptr[valid] == 0) { 1.1544 + /* parse latitude and longitude */ 1.1545 + done |= pgl_scan(&strptr, &lat, &lon); 1.1546 + done |= pgl_scan(&strptr, &lat, &lon); 1.1547 + /* parse radius (while incrementing strptr by number of bytes parsed) */ 1.1548 + valid = 0; 1.1549 + if (sscanf(strptr, " %lf %n", &radius, &valid) == 1) strptr += valid; 1.1550 + } 1.1551 + /* require end of string and both latitude and longitude being parsed */ 1.1552 + if (strptr[0] || done != PGL_SCAN_LATLON) { 1.1553 + ereport(ERROR, ( 1.1554 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1555 + errmsg("invalid input syntax for type ecircle: \"%s\"", str) 1.1556 + )); 1.1557 + } 1.1558 + /* allocate memory for result */ 1.1559 + circle = (pgl_circle *)palloc(sizeof(pgl_circle)); 1.1560 + /* set latitude, longitude, radius (and perform checks) */ 1.1561 + pgl_ecircle_set_latlon_radius(circle, lat, lon, radius); 1.1562 + /* return result */ 1.1563 + PG_RETURN_POINTER(circle); 1.1564 +} 1.1565 + 1.1566 +/* parse cluster ("ecluster" in SQL) */ 1.1567 +PG_FUNCTION_INFO_V1(pgl_ecluster_in); 1.1568 +Datum pgl_ecluster_in(PG_FUNCTION_ARGS) { 1.1569 + int i; 1.1570 + char *str = PG_GETARG_CSTRING(0); /* input string */ 1.1571 + char *str_lower; /* lower case version of input string */ 1.1572 + char *strptr; /* pointer to current reading position of input */ 1.1573 + int npoints_total = 0; /* total number of points in cluster */ 1.1574 + int nentries = 0; /* total number of entries */ 1.1575 + pgl_newentry *entries; /* array of pgl_newentry to create pgl_cluster */ 1.1576 + int entries_buflen = 4; /* maximum number of elements in entries array */ 1.1577 + int valid; /* number of valid chars processed */ 1.1578 + double lat, lon; /* latitude and longitude of parsed point */ 1.1579 + int entrytype; /* current entry type */ 1.1580 + int npoints; /* number of points in current entry */ 1.1581 + pgl_point *points; /* array of pgl_point for pgl_newentry */ 1.1582 + int points_buflen; /* maximum number of elements in points array */ 1.1583 + int done; /* return value of pgl_scan function */ 1.1584 + pgl_cluster *cluster; /* created cluster */ 1.1585 + /* lowercase input */ 1.1586 + str_lower = psprintf("%s", str); 1.1587 + for (strptr=str_lower; *strptr; strptr++) { 1.1588 + if (*strptr >= 'A' && *strptr <= 'Z') *strptr += 'a' - 'A'; 1.1589 + } 1.1590 + /* reset reading position to start of (lowercase) string */ 1.1591 + strptr = str_lower; 1.1592 + /* allocate initial buffer for entries */ 1.1593 + entries = palloc(entries_buflen * sizeof(pgl_newentry)); 1.1594 + /* parse until end of string */ 1.1595 + while (strptr[0]) { 1.1596 + /* require previous white-space or closing parenthesis before next token */ 1.1597 + if (strptr != str_lower && !isspace(strptr[-1]) && strptr[-1] != ')') { 1.1598 + goto pgl_ecluster_in_error; 1.1599 + } 1.1600 + /* ignore token "empty" */ 1.1601 + valid = 0; sscanf(strptr, " empty %n", &valid); 1.1602 + if (valid) { strptr += valid; continue; } 1.1603 + /* test for "point" token */ 1.1604 + valid = 0; sscanf(strptr, " point ( %n", &valid); 1.1605 + if (valid) { 1.1606 + strptr += valid; 1.1607 + entrytype = PGL_ENTRY_POINT; 1.1608 + goto pgl_ecluster_in_type_ok; 1.1609 + } 1.1610 + /* test for "path" token */ 1.1611 + valid = 0; sscanf(strptr, " path ( %n", &valid); 1.1612 + if (valid) { 1.1613 + strptr += valid; 1.1614 + entrytype = PGL_ENTRY_PATH; 1.1615 + goto pgl_ecluster_in_type_ok; 1.1616 + } 1.1617 + /* test for "outline" token */ 1.1618 + valid = 0; sscanf(strptr, " outline ( %n", &valid); 1.1619 + if (valid) { 1.1620 + strptr += valid; 1.1621 + entrytype = PGL_ENTRY_OUTLINE; 1.1622 + goto pgl_ecluster_in_type_ok; 1.1623 + } 1.1624 + /* test for "polygon" token */ 1.1625 + valid = 0; sscanf(strptr, " polygon ( %n", &valid); 1.1626 + if (valid) { 1.1627 + strptr += valid; 1.1628 + entrytype = PGL_ENTRY_POLYGON; 1.1629 + goto pgl_ecluster_in_type_ok; 1.1630 + } 1.1631 + /* error if no valid token found */ 1.1632 + goto pgl_ecluster_in_error; 1.1633 + pgl_ecluster_in_type_ok: 1.1634 + /* check if pgl_newentry array needs to grow */ 1.1635 + if (nentries == entries_buflen) { 1.1636 + pgl_newentry *newbuf; 1.1637 + entries_buflen *= 2; 1.1638 + newbuf = palloc(entries_buflen * sizeof(pgl_newentry)); 1.1639 + memcpy(newbuf, entries, nentries * sizeof(pgl_newentry)); 1.1640 + pfree(entries); 1.1641 + entries = newbuf; 1.1642 + } 1.1643 + /* reset number of points for current entry */ 1.1644 + npoints = 0; 1.1645 + /* allocate array for points */ 1.1646 + points_buflen = 4; 1.1647 + points = palloc(points_buflen * sizeof(pgl_point)); 1.1648 + /* parse until closing parenthesis */ 1.1649 + while (strptr[0] != ')') { 1.1650 + /* error on unexpected end of string */ 1.1651 + if (strptr[0] == 0) goto pgl_ecluster_in_error; 1.1652 + /* mark neither latitude nor longitude as read */ 1.1653 + done = PGL_SCAN_NONE; 1.1654 + /* require white-space before second, third, etc. point */ 1.1655 + if (npoints != 0 && !isspace(strptr[-1])) goto pgl_ecluster_in_error; 1.1656 + /* scan latitude (or longitude) */ 1.1657 + done |= pgl_scan(&strptr, &lat, &lon); 1.1658 + /* require white-space before second coordinate */ 1.1659 + if (strptr != str && !isspace(strptr[-1])) goto pgl_ecluster_in_error; 1.1660 + /* scan longitude (or latitude) */ 1.1661 + done |= pgl_scan(&strptr, &lat, &lon); 1.1662 + /* error unless both latitude and longitude were parsed */ 1.1663 + if (done != PGL_SCAN_LATLON) goto pgl_ecluster_in_error; 1.1664 + /* throw error if number of points is too high */ 1.1665 + if (npoints_total == PGL_CLUSTER_MAXPOINTS) { 1.1666 + ereport(ERROR, ( 1.1667 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1668 + errmsg( 1.1669 + "too many points for ecluster entry (maximum %i)", 1.1670 + PGL_CLUSTER_MAXPOINTS 1.1671 + ) 1.1672 + )); 1.1673 + } 1.1674 + /* check if pgl_point array needs to grow */ 1.1675 + if (npoints == points_buflen) { 1.1676 + pgl_point *newbuf; 1.1677 + points_buflen *= 2; 1.1678 + newbuf = palloc(points_buflen * sizeof(pgl_point)); 1.1679 + memcpy(newbuf, points, npoints * sizeof(pgl_point)); 1.1680 + pfree(points); 1.1681 + points = newbuf; 1.1682 + } 1.1683 + /* append point to pgl_point array (includes checks) */ 1.1684 + pgl_epoint_set_latlon(&(points[npoints++]), lat, lon); 1.1685 + /* increase total number of points */ 1.1686 + npoints_total++; 1.1687 + } 1.1688 + /* error if entry has no points */ 1.1689 + if (!npoints) goto pgl_ecluster_in_error; 1.1690 + /* entries with one point are automatically of type "point" */ 1.1691 + if (npoints == 1) entrytype = PGL_ENTRY_POINT; 1.1692 + /* if entries have more than one point */ 1.1693 + else { 1.1694 + /* throw error if entry type is "point" */ 1.1695 + if (entrytype == PGL_ENTRY_POINT) { 1.1696 + ereport(ERROR, ( 1.1697 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1698 + errmsg("invalid input syntax for type ecluster (point entry with more than one point)") 1.1699 + )); 1.1700 + } 1.1701 + /* coerce outlines and polygons with more than 2 points to be a path */ 1.1702 + if (npoints == 2) entrytype = PGL_ENTRY_PATH; 1.1703 + } 1.1704 + /* append entry to pgl_newentry array */ 1.1705 + entries[nentries].entrytype = entrytype; 1.1706 + entries[nentries].npoints = npoints; 1.1707 + entries[nentries].points = points; 1.1708 + nentries++; 1.1709 + /* consume closing parenthesis */ 1.1710 + strptr++; 1.1711 + /* consume white-space */ 1.1712 + while (isspace(strptr[0])) strptr++; 1.1713 + } 1.1714 + /* free lower case string */ 1.1715 + pfree(str_lower); 1.1716 + /* create cluster from pgl_newentry array */ 1.1717 + cluster = pgl_new_cluster(nentries, entries); 1.1718 + /* free pgl_newentry array */ 1.1719 + for (i=0; i<nentries; i++) pfree(entries[i].points); 1.1720 + pfree(entries); 1.1721 + /* set bounding circle of cluster and check east/west orientation */ 1.1722 + if (!pgl_finalize_cluster(cluster)) { 1.1723 + ereport(ERROR, ( 1.1724 + errcode(ERRCODE_DATA_EXCEPTION), 1.1725 + errmsg("can not determine east/west orientation for ecluster"), 1.1726 + errhint("Ensure that each entry has a longitude span of less than 180 degrees.") 1.1727 + )); 1.1728 + } 1.1729 + /* return cluster */ 1.1730 + PG_RETURN_POINTER(cluster); 1.1731 + /* code to throw error */ 1.1732 + pgl_ecluster_in_error: 1.1733 + ereport(ERROR, ( 1.1734 + errcode(ERRCODE_INVALID_TEXT_REPRESENTATION), 1.1735 + errmsg("invalid input syntax for type ecluster: \"%s\"", str) 1.1736 + )); 1.1737 +} 1.1738 + 1.1739 +/* convert point ("epoint") to string representation */ 1.1740 +PG_FUNCTION_INFO_V1(pgl_epoint_out); 1.1741 +Datum pgl_epoint_out(PG_FUNCTION_ARGS) { 1.1742 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1743 + char latstr[PGL_NUMBUFLEN]; 1.1744 + char lonstr[PGL_NUMBUFLEN]; 1.1745 + pgl_print_lat(latstr, point->lat); 1.1746 + pgl_print_lon(lonstr, point->lon); 1.1747 + PG_RETURN_CSTRING(psprintf("%s %s", latstr, lonstr)); 1.1748 +} 1.1749 + 1.1750 +/* convert box ("ebox") to string representation */ 1.1751 +PG_FUNCTION_INFO_V1(pgl_ebox_out); 1.1752 +Datum pgl_ebox_out(PG_FUNCTION_ARGS) { 1.1753 + pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0); 1.1754 + double lon_min = box->lon_min; 1.1755 + double lon_max = box->lon_max; 1.1756 + char lat_min_str[PGL_NUMBUFLEN]; 1.1757 + char lat_max_str[PGL_NUMBUFLEN]; 1.1758 + char lon_min_str[PGL_NUMBUFLEN]; 1.1759 + char lon_max_str[PGL_NUMBUFLEN]; 1.1760 + /* return string "empty" if box is set to be empty */ 1.1761 + if (box->lat_min > box->lat_max) PG_RETURN_CSTRING("empty"); 1.1762 + /* use boundaries exceeding W180 or E180 if 180th meridian is enclosed */ 1.1763 + /* (required since pgl_box_in orders the longitude boundaries) */ 1.1764 + if (lon_min > lon_max) { 1.1765 + if (lon_min + lon_max >= 0) lon_min -= 360; 1.1766 + else lon_max += 360; 1.1767 + } 1.1768 + /* format and return result */ 1.1769 + pgl_print_lat(lat_min_str, box->lat_min); 1.1770 + pgl_print_lat(lat_max_str, box->lat_max); 1.1771 + pgl_print_lon(lon_min_str, lon_min); 1.1772 + pgl_print_lon(lon_max_str, lon_max); 1.1773 + PG_RETURN_CSTRING(psprintf( 1.1774 + "%s %s %s %s", 1.1775 + lat_min_str, lon_min_str, lat_max_str, lon_max_str 1.1776 + )); 1.1777 +} 1.1778 + 1.1779 +/* convert circle ("ecircle") to string representation */ 1.1780 +PG_FUNCTION_INFO_V1(pgl_ecircle_out); 1.1781 +Datum pgl_ecircle_out(PG_FUNCTION_ARGS) { 1.1782 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0); 1.1783 + char latstr[PGL_NUMBUFLEN]; 1.1784 + char lonstr[PGL_NUMBUFLEN]; 1.1785 + char radstr[PGL_NUMBUFLEN]; 1.1786 + pgl_print_lat(latstr, circle->center.lat); 1.1787 + pgl_print_lon(lonstr, circle->center.lon); 1.1788 + pgl_print_float(radstr, circle->radius); 1.1789 + PG_RETURN_CSTRING(psprintf("%s %s %s", latstr, lonstr, radstr)); 1.1790 +} 1.1791 + 1.1792 +/* convert cluster ("ecluster") to string representation */ 1.1793 +PG_FUNCTION_INFO_V1(pgl_ecluster_out); 1.1794 +Datum pgl_ecluster_out(PG_FUNCTION_ARGS) { 1.1795 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); 1.1796 + char latstr[PGL_NUMBUFLEN]; /* string buffer for latitude */ 1.1797 + char lonstr[PGL_NUMBUFLEN]; /* string buffer for longitude */ 1.1798 + char ***strings; /* array of array of strings */ 1.1799 + char *string; /* string of current token */ 1.1800 + char *res, *resptr; /* result and pointer to current write position */ 1.1801 + size_t reslen = 1; /* length of result (init with 1 for terminator) */ 1.1802 + int npoints; /* number of points of current entry */ 1.1803 + int i, j; /* i: entry, j: point in entry */ 1.1804 + /* handle empty clusters */ 1.1805 + if (cluster->nentries == 0) { 1.1806 + /* free detoasted cluster (if copy) */ 1.1807 + PG_FREE_IF_COPY(cluster, 0); 1.1808 + /* return static result */ 1.1809 + PG_RETURN_CSTRING("empty"); 1.1810 + } 1.1811 + /* allocate array of array of strings */ 1.1812 + strings = palloc(cluster->nentries * sizeof(char **)); 1.1813 + /* iterate over all entries in cluster */ 1.1814 + for (i=0; i<cluster->nentries; i++) { 1.1815 + /* get number of points in entry */ 1.1816 + npoints = cluster->entries[i].npoints; 1.1817 + /* allocate array of strings (one string for each point plus two extra) */ 1.1818 + strings[i] = palloc((2 + npoints) * sizeof(char *)); 1.1819 + /* determine opening string */ 1.1820 + switch (cluster->entries[i].entrytype) { 1.1821 + case PGL_ENTRY_POINT: string = (i==0)?"point (" :" point ("; break; 1.1822 + case PGL_ENTRY_PATH: string = (i==0)?"path (" :" path ("; break; 1.1823 + case PGL_ENTRY_OUTLINE: string = (i==0)?"outline (":" outline ("; break; 1.1824 + case PGL_ENTRY_POLYGON: string = (i==0)?"polygon (":" polygon ("; break; 1.1825 + default: string = (i==0)?"unknown" :" unknown"; 1.1826 + } 1.1827 + /* use opening string as first string in array */ 1.1828 + strings[i][0] = string; 1.1829 + /* update result length (for allocating result string later) */ 1.1830 + reslen += strlen(string); 1.1831 + /* iterate over all points */ 1.1832 + for (j=0; j<npoints; j++) { 1.1833 + /* create string representation of point */ 1.1834 + pgl_print_lat(latstr, PGL_ENTRY_POINTS(cluster, i)[j].lat); 1.1835 + pgl_print_lon(lonstr, PGL_ENTRY_POINTS(cluster, i)[j].lon); 1.1836 + string = psprintf((j == 0) ? "%s %s" : " %s %s", latstr, lonstr); 1.1837 + /* copy string pointer to string array */ 1.1838 + strings[i][j+1] = string; 1.1839 + /* update result length (for allocating result string later) */ 1.1840 + reslen += strlen(string); 1.1841 + } 1.1842 + /* use closing parenthesis as last string in array */ 1.1843 + strings[i][npoints+1] = ")"; 1.1844 + /* update result length (for allocating result string later) */ 1.1845 + reslen++; 1.1846 + } 1.1847 + /* allocate result string */ 1.1848 + res = palloc(reslen); 1.1849 + /* set write pointer to begin of result string */ 1.1850 + resptr = res; 1.1851 + /* copy strings into result string */ 1.1852 + for (i=0; i<cluster->nentries; i++) { 1.1853 + npoints = cluster->entries[i].npoints; 1.1854 + for (j=0; j<npoints+2; j++) { 1.1855 + string = strings[i][j]; 1.1856 + strcpy(resptr, string); 1.1857 + resptr += strlen(string); 1.1858 + /* free strings allocated by psprintf */ 1.1859 + if (j != 0 && j != npoints+1) pfree(string); 1.1860 + } 1.1861 + /* free array of strings */ 1.1862 + pfree(strings[i]); 1.1863 + } 1.1864 + /* free array of array of strings */ 1.1865 + pfree(strings); 1.1866 + /* free detoasted cluster (if copy) */ 1.1867 + PG_FREE_IF_COPY(cluster, 0); 1.1868 + /* return result */ 1.1869 + PG_RETURN_CSTRING(res); 1.1870 +} 1.1871 + 1.1872 +/* binary input function for point ("epoint") */ 1.1873 +PG_FUNCTION_INFO_V1(pgl_epoint_recv); 1.1874 +Datum pgl_epoint_recv(PG_FUNCTION_ARGS) { 1.1875 + StringInfo buf = (StringInfo)PG_GETARG_POINTER(0); 1.1876 + pgl_point *point = (pgl_point *)palloc(sizeof(pgl_point)); 1.1877 + point->lat = pq_getmsgfloat8(buf); 1.1878 + point->lon = pq_getmsgfloat8(buf); 1.1879 + PG_RETURN_POINTER(point); 1.1880 +} 1.1881 + 1.1882 +/* binary input function for box ("ebox") */ 1.1883 +PG_FUNCTION_INFO_V1(pgl_ebox_recv); 1.1884 +Datum pgl_ebox_recv(PG_FUNCTION_ARGS) { 1.1885 + StringInfo buf = (StringInfo)PG_GETARG_POINTER(0); 1.1886 + pgl_box *box = (pgl_box *)palloc(sizeof(pgl_box)); 1.1887 + box->lat_min = pq_getmsgfloat8(buf); 1.1888 + box->lat_max = pq_getmsgfloat8(buf); 1.1889 + box->lon_min = pq_getmsgfloat8(buf); 1.1890 + box->lon_max = pq_getmsgfloat8(buf); 1.1891 + PG_RETURN_POINTER(box); 1.1892 +} 1.1893 + 1.1894 +/* binary input function for circle ("ecircle") */ 1.1895 +PG_FUNCTION_INFO_V1(pgl_ecircle_recv); 1.1896 +Datum pgl_ecircle_recv(PG_FUNCTION_ARGS) { 1.1897 + StringInfo buf = (StringInfo)PG_GETARG_POINTER(0); 1.1898 + pgl_circle *circle = (pgl_circle *)palloc(sizeof(pgl_circle)); 1.1899 + circle->center.lat = pq_getmsgfloat8(buf); 1.1900 + circle->center.lon = pq_getmsgfloat8(buf); 1.1901 + circle->radius = pq_getmsgfloat8(buf); 1.1902 + PG_RETURN_POINTER(circle); 1.1903 +} 1.1904 + 1.1905 +/* TODO: binary receive function for cluster */ 1.1906 + 1.1907 +/* binary output function for point ("epoint") */ 1.1908 +PG_FUNCTION_INFO_V1(pgl_epoint_send); 1.1909 +Datum pgl_epoint_send(PG_FUNCTION_ARGS) { 1.1910 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1911 + StringInfoData buf; 1.1912 + pq_begintypsend(&buf); 1.1913 + pq_sendfloat8(&buf, point->lat); 1.1914 + pq_sendfloat8(&buf, point->lon); 1.1915 + PG_RETURN_BYTEA_P(pq_endtypsend(&buf)); 1.1916 +} 1.1917 + 1.1918 +/* binary output function for box ("ebox") */ 1.1919 +PG_FUNCTION_INFO_V1(pgl_ebox_send); 1.1920 +Datum pgl_ebox_send(PG_FUNCTION_ARGS) { 1.1921 + pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0); 1.1922 + StringInfoData buf; 1.1923 + pq_begintypsend(&buf); 1.1924 + pq_sendfloat8(&buf, box->lat_min); 1.1925 + pq_sendfloat8(&buf, box->lat_max); 1.1926 + pq_sendfloat8(&buf, box->lon_min); 1.1927 + pq_sendfloat8(&buf, box->lon_max); 1.1928 + PG_RETURN_BYTEA_P(pq_endtypsend(&buf)); 1.1929 +} 1.1930 + 1.1931 +/* binary output function for circle ("ecircle") */ 1.1932 +PG_FUNCTION_INFO_V1(pgl_ecircle_send); 1.1933 +Datum pgl_ecircle_send(PG_FUNCTION_ARGS) { 1.1934 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0); 1.1935 + StringInfoData buf; 1.1936 + pq_begintypsend(&buf); 1.1937 + pq_sendfloat8(&buf, circle->center.lat); 1.1938 + pq_sendfloat8(&buf, circle->center.lon); 1.1939 + pq_sendfloat8(&buf, circle->radius); 1.1940 + PG_RETURN_BYTEA_P(pq_endtypsend(&buf)); 1.1941 +} 1.1942 + 1.1943 +/* TODO: binary send functions for cluster */ 1.1944 + 1.1945 +/* cast point ("epoint") to box ("ebox") */ 1.1946 +PG_FUNCTION_INFO_V1(pgl_epoint_to_ebox); 1.1947 +Datum pgl_epoint_to_ebox(PG_FUNCTION_ARGS) { 1.1948 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1949 + pgl_box *box = palloc(sizeof(pgl_box)); 1.1950 + box->lat_min = point->lat; 1.1951 + box->lat_max = point->lat; 1.1952 + box->lon_min = point->lon; 1.1953 + box->lon_max = point->lon; 1.1954 + PG_RETURN_POINTER(box); 1.1955 +} 1.1956 + 1.1957 +/* cast point ("epoint") to circle ("ecircle") */ 1.1958 +PG_FUNCTION_INFO_V1(pgl_epoint_to_ecircle); 1.1959 +Datum pgl_epoint_to_ecircle(PG_FUNCTION_ARGS) { 1.1960 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1961 + pgl_circle *circle = palloc(sizeof(pgl_box)); 1.1962 + circle->center = *point; 1.1963 + circle->radius = 0; 1.1964 + PG_RETURN_POINTER(circle); 1.1965 +} 1.1966 + 1.1967 +/* cast point ("epoint") to cluster ("ecluster") */ 1.1968 +PG_FUNCTION_INFO_V1(pgl_epoint_to_ecluster); 1.1969 +Datum pgl_epoint_to_ecluster(PG_FUNCTION_ARGS) { 1.1970 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.1971 + pgl_newentry entry; 1.1972 + entry.entrytype = PGL_ENTRY_POINT; 1.1973 + entry.npoints = 1; 1.1974 + entry.points = point; 1.1975 + PG_RETURN_POINTER(pgl_new_cluster(1, &entry)); 1.1976 +} 1.1977 + 1.1978 +/* cast box ("ebox") to cluster ("ecluster") */ 1.1979 +#define pgl_ebox_to_ecluster_macro(i, a, b) \ 1.1980 + entries[i].entrytype = PGL_ENTRY_POLYGON; \ 1.1981 + entries[i].npoints = 4; \ 1.1982 + entries[i].points = points[i]; \ 1.1983 + points[i][0].lat = box->lat_min; \ 1.1984 + points[i][0].lon = (a); \ 1.1985 + points[i][1].lat = box->lat_min; \ 1.1986 + points[i][1].lon = (b); \ 1.1987 + points[i][2].lat = box->lat_max; \ 1.1988 + points[i][2].lon = (b); \ 1.1989 + points[i][3].lat = box->lat_max; \ 1.1990 + points[i][3].lon = (a); 1.1991 +PG_FUNCTION_INFO_V1(pgl_ebox_to_ecluster); 1.1992 +Datum pgl_ebox_to_ecluster(PG_FUNCTION_ARGS) { 1.1993 + pgl_box *box = (pgl_box *)PG_GETARG_POINTER(0); 1.1994 + double lon, dlon; 1.1995 + int nentries; 1.1996 + pgl_newentry entries[3]; 1.1997 + pgl_point points[3][4]; 1.1998 + if (box->lat_min > box->lat_max) { 1.1999 + nentries = 0; 1.2000 + } else if (box->lon_min > box->lon_max) { 1.2001 + if (box->lon_min < 0) { 1.2002 + lon = pgl_round((box->lon_min + 180) / 2.0); 1.2003 + nentries = 3; 1.2004 + pgl_ebox_to_ecluster_macro(0, box->lon_min, lon); 1.2005 + pgl_ebox_to_ecluster_macro(1, lon, 180); 1.2006 + pgl_ebox_to_ecluster_macro(2, -180, box->lon_max); 1.2007 + } else if (box->lon_max > 0) { 1.2008 + lon = pgl_round((box->lon_max - 180) / 2.0); 1.2009 + nentries = 3; 1.2010 + pgl_ebox_to_ecluster_macro(0, box->lon_min, 180); 1.2011 + pgl_ebox_to_ecluster_macro(1, -180, lon); 1.2012 + pgl_ebox_to_ecluster_macro(2, lon, box->lon_max); 1.2013 + } else { 1.2014 + nentries = 2; 1.2015 + pgl_ebox_to_ecluster_macro(0, box->lon_min, 180); 1.2016 + pgl_ebox_to_ecluster_macro(1, -180, box->lon_max); 1.2017 + } 1.2018 + } else { 1.2019 + dlon = pgl_round(box->lon_max - box->lon_min); 1.2020 + if (dlon < 180) { 1.2021 + nentries = 1; 1.2022 + pgl_ebox_to_ecluster_macro(0, box->lon_min, box->lon_max); 1.2023 + } else { 1.2024 + lon = pgl_round((box->lon_min + box->lon_max) / 2.0); 1.2025 + if ( 1.2026 + pgl_round(lon - box->lon_min) < 180 && 1.2027 + pgl_round(box->lon_max - lon) < 180 1.2028 + ) { 1.2029 + nentries = 2; 1.2030 + pgl_ebox_to_ecluster_macro(0, box->lon_min, lon); 1.2031 + pgl_ebox_to_ecluster_macro(1, lon, box->lon_max); 1.2032 + } else { 1.2033 + nentries = 3; 1.2034 + pgl_ebox_to_ecluster_macro(0, box->lon_min, -60); 1.2035 + pgl_ebox_to_ecluster_macro(1, -60, 60); 1.2036 + pgl_ebox_to_ecluster_macro(2, 60, box->lon_max); 1.2037 + } 1.2038 + } 1.2039 + } 1.2040 + PG_RETURN_POINTER(pgl_new_cluster(nentries, entries)); 1.2041 +} 1.2042 + 1.2043 +/* extract latitude from point ("epoint") */ 1.2044 +PG_FUNCTION_INFO_V1(pgl_epoint_lat); 1.2045 +Datum pgl_epoint_lat(PG_FUNCTION_ARGS) { 1.2046 + PG_RETURN_FLOAT8(((pgl_point *)PG_GETARG_POINTER(0))->lat); 1.2047 +} 1.2048 + 1.2049 +/* extract longitude from point ("epoint") */ 1.2050 +PG_FUNCTION_INFO_V1(pgl_epoint_lon); 1.2051 +Datum pgl_epoint_lon(PG_FUNCTION_ARGS) { 1.2052 + PG_RETURN_FLOAT8(((pgl_point *)PG_GETARG_POINTER(0))->lon); 1.2053 +} 1.2054 + 1.2055 +/* extract minimum latitude from box ("ebox") */ 1.2056 +PG_FUNCTION_INFO_V1(pgl_ebox_lat_min); 1.2057 +Datum pgl_ebox_lat_min(PG_FUNCTION_ARGS) { 1.2058 + PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lat_min); 1.2059 +} 1.2060 + 1.2061 +/* extract maximum latitude from box ("ebox") */ 1.2062 +PG_FUNCTION_INFO_V1(pgl_ebox_lat_max); 1.2063 +Datum pgl_ebox_lat_max(PG_FUNCTION_ARGS) { 1.2064 + PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lat_max); 1.2065 +} 1.2066 + 1.2067 +/* extract minimum longitude from box ("ebox") */ 1.2068 +PG_FUNCTION_INFO_V1(pgl_ebox_lon_min); 1.2069 +Datum pgl_ebox_lon_min(PG_FUNCTION_ARGS) { 1.2070 + PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lon_min); 1.2071 +} 1.2072 + 1.2073 +/* extract maximum longitude from box ("ebox") */ 1.2074 +PG_FUNCTION_INFO_V1(pgl_ebox_lon_max); 1.2075 +Datum pgl_ebox_lon_max(PG_FUNCTION_ARGS) { 1.2076 + PG_RETURN_FLOAT8(((pgl_box *)PG_GETARG_POINTER(0))->lon_max); 1.2077 +} 1.2078 + 1.2079 +/* extract center point from circle ("ecircle") */ 1.2080 +PG_FUNCTION_INFO_V1(pgl_ecircle_center); 1.2081 +Datum pgl_ecircle_center(PG_FUNCTION_ARGS) { 1.2082 + PG_RETURN_POINTER(&(((pgl_circle *)PG_GETARG_POINTER(0))->center)); 1.2083 +} 1.2084 + 1.2085 +/* extract radius from circle ("ecircle") */ 1.2086 +PG_FUNCTION_INFO_V1(pgl_ecircle_radius); 1.2087 +Datum pgl_ecircle_radius(PG_FUNCTION_ARGS) { 1.2088 + PG_RETURN_FLOAT8(((pgl_circle *)PG_GETARG_POINTER(0))->radius); 1.2089 +} 1.2090 + 1.2091 +/* check if point is inside box (overlap operator "&&") in SQL */ 1.2092 +PG_FUNCTION_INFO_V1(pgl_epoint_ebox_overlap); 1.2093 +Datum pgl_epoint_ebox_overlap(PG_FUNCTION_ARGS) { 1.2094 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.2095 + pgl_box *box = (pgl_box *)PG_GETARG_POINTER(1); 1.2096 + PG_RETURN_BOOL(pgl_point_in_box(point, box)); 1.2097 +} 1.2098 + 1.2099 +/* check if point is inside circle (overlap operator "&&") in SQL */ 1.2100 +PG_FUNCTION_INFO_V1(pgl_epoint_ecircle_overlap); 1.2101 +Datum pgl_epoint_ecircle_overlap(PG_FUNCTION_ARGS) { 1.2102 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.2103 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(1); 1.2104 + PG_RETURN_BOOL( 1.2105 + pgl_distance( 1.2106 + point->lat, point->lon, 1.2107 + circle->center.lat, circle->center.lon 1.2108 + ) <= circle->radius 1.2109 + ); 1.2110 +} 1.2111 + 1.2112 +/* check if point is inside cluster (overlap operator "&&") in SQL */ 1.2113 +PG_FUNCTION_INFO_V1(pgl_epoint_ecluster_overlap); 1.2114 +Datum pgl_epoint_ecluster_overlap(PG_FUNCTION_ARGS) { 1.2115 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.2116 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2117 + bool retval = pgl_point_in_cluster(point, cluster); 1.2118 + PG_FREE_IF_COPY(cluster, 1); 1.2119 + PG_RETURN_BOOL(retval); 1.2120 +} 1.2121 + 1.2122 +/* check if two boxes overlap (overlap operator "&&") in SQL */ 1.2123 +PG_FUNCTION_INFO_V1(pgl_ebox_overlap); 1.2124 +Datum pgl_ebox_overlap(PG_FUNCTION_ARGS) { 1.2125 + pgl_box *box1 = (pgl_box *)PG_GETARG_POINTER(0); 1.2126 + pgl_box *box2 = (pgl_box *)PG_GETARG_POINTER(1); 1.2127 + PG_RETURN_BOOL(pgl_boxes_overlap(box1, box2)); 1.2128 +} 1.2129 + 1.2130 +/* check if two circles overlap (overlap operator "&&") in SQL */ 1.2131 +PG_FUNCTION_INFO_V1(pgl_ecircle_overlap); 1.2132 +Datum pgl_ecircle_overlap(PG_FUNCTION_ARGS) { 1.2133 + pgl_circle *circle1 = (pgl_circle *)PG_GETARG_POINTER(0); 1.2134 + pgl_circle *circle2 = (pgl_circle *)PG_GETARG_POINTER(1); 1.2135 + PG_RETURN_BOOL( 1.2136 + pgl_distance( 1.2137 + circle1->center.lat, circle1->center.lon, 1.2138 + circle2->center.lat, circle2->center.lon 1.2139 + ) <= circle1->radius + circle2->radius 1.2140 + ); 1.2141 +} 1.2142 + 1.2143 +/* check if circle and cluster overlap (overlap operator "&&") in SQL */ 1.2144 +PG_FUNCTION_INFO_V1(pgl_ecircle_ecluster_overlap); 1.2145 +Datum pgl_ecircle_ecluster_overlap(PG_FUNCTION_ARGS) { 1.2146 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0); 1.2147 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2148 + bool retval = ( 1.2149 + pgl_point_cluster_distance(&(circle->center), cluster) <= circle->radius 1.2150 + ); 1.2151 + PG_FREE_IF_COPY(cluster, 1); 1.2152 + PG_RETURN_BOOL(retval); 1.2153 +} 1.2154 + 1.2155 +/* calculate distance between two points ("<->" operator) in SQL */ 1.2156 +PG_FUNCTION_INFO_V1(pgl_epoint_distance); 1.2157 +Datum pgl_epoint_distance(PG_FUNCTION_ARGS) { 1.2158 + pgl_point *point1 = (pgl_point *)PG_GETARG_POINTER(0); 1.2159 + pgl_point *point2 = (pgl_point *)PG_GETARG_POINTER(1); 1.2160 + PG_RETURN_FLOAT8(pgl_distance( 1.2161 + point1->lat, point1->lon, point2->lat, point2->lon 1.2162 + )); 1.2163 +} 1.2164 + 1.2165 +/* calculate point to circle distance ("<->" operator) in SQL */ 1.2166 +PG_FUNCTION_INFO_V1(pgl_epoint_ecircle_distance); 1.2167 +Datum pgl_epoint_ecircle_distance(PG_FUNCTION_ARGS) { 1.2168 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.2169 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(1); 1.2170 + double distance = pgl_distance( 1.2171 + point->lat, point->lon, circle->center.lat, circle->center.lon 1.2172 + ) - circle->radius; 1.2173 + PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance); 1.2174 +} 1.2175 + 1.2176 +/* calculate point to cluster distance ("<->" operator) in SQL */ 1.2177 +PG_FUNCTION_INFO_V1(pgl_epoint_ecluster_distance); 1.2178 +Datum pgl_epoint_ecluster_distance(PG_FUNCTION_ARGS) { 1.2179 + pgl_point *point = (pgl_point *)PG_GETARG_POINTER(0); 1.2180 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2181 + double distance = pgl_point_cluster_distance(point, cluster); 1.2182 + PG_FREE_IF_COPY(cluster, 1); 1.2183 + PG_RETURN_FLOAT8(distance); 1.2184 +} 1.2185 + 1.2186 +/* calculate distance between two circles ("<->" operator) in SQL */ 1.2187 +PG_FUNCTION_INFO_V1(pgl_ecircle_distance); 1.2188 +Datum pgl_ecircle_distance(PG_FUNCTION_ARGS) { 1.2189 + pgl_circle *circle1 = (pgl_circle *)PG_GETARG_POINTER(0); 1.2190 + pgl_circle *circle2 = (pgl_circle *)PG_GETARG_POINTER(1); 1.2191 + double distance = pgl_distance( 1.2192 + circle1->center.lat, circle1->center.lon, 1.2193 + circle2->center.lat, circle2->center.lon 1.2194 + ) - (circle1->radius + circle2->radius); 1.2195 + PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance); 1.2196 +} 1.2197 + 1.2198 +/* calculate circle to cluster distance ("<->" operator) in SQL */ 1.2199 +PG_FUNCTION_INFO_V1(pgl_ecircle_ecluster_distance); 1.2200 +Datum pgl_ecircle_ecluster_distance(PG_FUNCTION_ARGS) { 1.2201 + pgl_circle *circle = (pgl_circle *)PG_GETARG_POINTER(0); 1.2202 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2203 + double distance = ( 1.2204 + pgl_point_cluster_distance(&(circle->center), cluster) - circle->radius 1.2205 + ); 1.2206 + PG_FREE_IF_COPY(cluster, 1); 1.2207 + PG_RETURN_FLOAT8((distance <= 0) ? 0 : distance); 1.2208 +} 1.2209 + 1.2210 + 1.2211 +/*-----------------------------------------------------------* 1.2212 + * B-tree comparison operators and index support functions * 1.2213 + *-----------------------------------------------------------*/ 1.2214 + 1.2215 +/* macro for a B-tree operator (without detoasting) */ 1.2216 +#define PGL_BTREE_OPER(func, type, cmpfunc, oper) \ 1.2217 + PG_FUNCTION_INFO_V1(func); \ 1.2218 + Datum func(PG_FUNCTION_ARGS) { \ 1.2219 + type *a = (type *)PG_GETARG_POINTER(0); \ 1.2220 + type *b = (type *)PG_GETARG_POINTER(1); \ 1.2221 + PG_RETURN_BOOL(cmpfunc(a, b) oper 0); \ 1.2222 + } 1.2223 + 1.2224 +/* macro for a B-tree comparison function (without detoasting) */ 1.2225 +#define PGL_BTREE_CMP(func, type, cmpfunc) \ 1.2226 + PG_FUNCTION_INFO_V1(func); \ 1.2227 + Datum func(PG_FUNCTION_ARGS) { \ 1.2228 + type *a = (type *)PG_GETARG_POINTER(0); \ 1.2229 + type *b = (type *)PG_GETARG_POINTER(1); \ 1.2230 + PG_RETURN_INT32(cmpfunc(a, b)); \ 1.2231 + } 1.2232 + 1.2233 +/* macro for a B-tree operator (with detoasting) */ 1.2234 +#define PGL_BTREE_OPER_DETOAST(func, type, cmpfunc, oper) \ 1.2235 + PG_FUNCTION_INFO_V1(func); \ 1.2236 + Datum func(PG_FUNCTION_ARGS) { \ 1.2237 + bool res; \ 1.2238 + type *a = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); \ 1.2239 + type *b = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); \ 1.2240 + res = cmpfunc(a, b) oper 0; \ 1.2241 + PG_FREE_IF_COPY(a, 0); \ 1.2242 + PG_FREE_IF_COPY(b, 1); \ 1.2243 + PG_RETURN_BOOL(res); \ 1.2244 + } 1.2245 + 1.2246 +/* macro for a B-tree comparison function (with detoasting) */ 1.2247 +#define PGL_BTREE_CMP_DETOAST(func, type, cmpfunc) \ 1.2248 + PG_FUNCTION_INFO_V1(func); \ 1.2249 + Datum func(PG_FUNCTION_ARGS) { \ 1.2250 + int32_t res; \ 1.2251 + type *a = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); \ 1.2252 + type *b = (type *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); \ 1.2253 + res = cmpfunc(a, b); \ 1.2254 + PG_FREE_IF_COPY(a, 0); \ 1.2255 + PG_FREE_IF_COPY(b, 1); \ 1.2256 + PG_RETURN_INT32(res); \ 1.2257 + } 1.2258 + 1.2259 +/* B-tree operators and comparison function for point */ 1.2260 +PGL_BTREE_OPER(pgl_btree_epoint_lt, pgl_point, pgl_point_cmp, <) 1.2261 +PGL_BTREE_OPER(pgl_btree_epoint_le, pgl_point, pgl_point_cmp, <=) 1.2262 +PGL_BTREE_OPER(pgl_btree_epoint_eq, pgl_point, pgl_point_cmp, ==) 1.2263 +PGL_BTREE_OPER(pgl_btree_epoint_ne, pgl_point, pgl_point_cmp, !=) 1.2264 +PGL_BTREE_OPER(pgl_btree_epoint_ge, pgl_point, pgl_point_cmp, >=) 1.2265 +PGL_BTREE_OPER(pgl_btree_epoint_gt, pgl_point, pgl_point_cmp, >) 1.2266 +PGL_BTREE_CMP(pgl_btree_epoint_cmp, pgl_point, pgl_point_cmp) 1.2267 + 1.2268 +/* B-tree operators and comparison function for box */ 1.2269 +PGL_BTREE_OPER(pgl_btree_ebox_lt, pgl_box, pgl_box_cmp, <) 1.2270 +PGL_BTREE_OPER(pgl_btree_ebox_le, pgl_box, pgl_box_cmp, <=) 1.2271 +PGL_BTREE_OPER(pgl_btree_ebox_eq, pgl_box, pgl_box_cmp, ==) 1.2272 +PGL_BTREE_OPER(pgl_btree_ebox_ne, pgl_box, pgl_box_cmp, !=) 1.2273 +PGL_BTREE_OPER(pgl_btree_ebox_ge, pgl_box, pgl_box_cmp, >=) 1.2274 +PGL_BTREE_OPER(pgl_btree_ebox_gt, pgl_box, pgl_box_cmp, >) 1.2275 +PGL_BTREE_CMP(pgl_btree_ebox_cmp, pgl_box, pgl_box_cmp) 1.2276 + 1.2277 +/* B-tree operators and comparison function for circle */ 1.2278 +PGL_BTREE_OPER(pgl_btree_ecircle_lt, pgl_circle, pgl_circle_cmp, <) 1.2279 +PGL_BTREE_OPER(pgl_btree_ecircle_le, pgl_circle, pgl_circle_cmp, <=) 1.2280 +PGL_BTREE_OPER(pgl_btree_ecircle_eq, pgl_circle, pgl_circle_cmp, ==) 1.2281 +PGL_BTREE_OPER(pgl_btree_ecircle_ne, pgl_circle, pgl_circle_cmp, !=) 1.2282 +PGL_BTREE_OPER(pgl_btree_ecircle_ge, pgl_circle, pgl_circle_cmp, >=) 1.2283 +PGL_BTREE_OPER(pgl_btree_ecircle_gt, pgl_circle, pgl_circle_cmp, >) 1.2284 +PGL_BTREE_CMP(pgl_btree_ecircle_cmp, pgl_circle, pgl_circle_cmp) 1.2285 + 1.2286 + 1.2287 +/*--------------------------------* 1.2288 + * GiST index support functions * 1.2289 + *--------------------------------*/ 1.2290 + 1.2291 +/* GiST "consistent" support function */ 1.2292 +PG_FUNCTION_INFO_V1(pgl_gist_consistent); 1.2293 +Datum pgl_gist_consistent(PG_FUNCTION_ARGS) { 1.2294 + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); 1.2295 + pgl_keyptr key = (pgl_keyptr)DatumGetPointer(entry->key); 1.2296 + StrategyNumber strategy = (StrategyNumber)PG_GETARG_UINT16(2); 1.2297 + bool *recheck = (bool *)PG_GETARG_POINTER(4); 1.2298 + /* demand recheck because index and query methods are lossy */ 1.2299 + *recheck = true; 1.2300 + /* strategy number 11: equality of two points */ 1.2301 + if (strategy == 11) { 1.2302 + /* query datum is another point */ 1.2303 + pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1); 1.2304 + /* convert other point to key */ 1.2305 + pgl_pointkey querykey; 1.2306 + pgl_point_to_key(query, querykey); 1.2307 + /* return true if both keys overlap */ 1.2308 + PG_RETURN_BOOL(pgl_keys_overlap(key, querykey)); 1.2309 + } 1.2310 + /* strategy number 13: equality of two circles */ 1.2311 + if (strategy == 13) { 1.2312 + /* query datum is another circle */ 1.2313 + pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1); 1.2314 + /* convert other circle to key */ 1.2315 + pgl_areakey querykey; 1.2316 + pgl_circle_to_key(query, querykey); 1.2317 + /* return true if both keys overlap */ 1.2318 + PG_RETURN_BOOL(pgl_keys_overlap(key, querykey)); 1.2319 + } 1.2320 + /* for all remaining strategies, keys on empty objects produce no match */ 1.2321 + /* (check necessary because query radius may be infinite) */ 1.2322 + if (PGL_KEY_IS_EMPTY(key)) PG_RETURN_BOOL(false); 1.2323 + /* strategy number 21: overlapping with point */ 1.2324 + if (strategy == 21) { 1.2325 + /* query datum is a point */ 1.2326 + pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1); 1.2327 + /* return true if estimated distance (allowed to be smaller than real 1.2328 + distance) between index key and point is zero */ 1.2329 + PG_RETURN_BOOL(pgl_estimate_key_distance(key, query) == 0); 1.2330 + } 1.2331 + /* strategy number 22: (point) overlapping with box */ 1.2332 + if (strategy == 22) { 1.2333 + /* query datum is a box */ 1.2334 + pgl_box *query = (pgl_box *)PG_GETARG_POINTER(1); 1.2335 + /* determine bounding box of indexed key */ 1.2336 + pgl_box keybox; 1.2337 + pgl_key_to_box(key, &keybox); 1.2338 + /* return true if query box overlaps with bounding box of indexed key */ 1.2339 + PG_RETURN_BOOL(pgl_boxes_overlap(query, &keybox)); 1.2340 + } 1.2341 + /* strategy number 23: overlapping with circle */ 1.2342 + if (strategy == 23) { 1.2343 + /* query datum is a circle */ 1.2344 + pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1); 1.2345 + /* return true if estimated distance (allowed to be smaller than real 1.2346 + distance) between index key and circle center is smaller than radius */ 1.2347 + PG_RETURN_BOOL( 1.2348 + pgl_estimate_key_distance(key, &(query->center)) <= query->radius 1.2349 + ); 1.2350 + } 1.2351 + /* strategy number 24: overlapping with cluster */ 1.2352 + if (strategy == 24) { 1.2353 + bool retval; /* return value */ 1.2354 + /* query datum is a cluster */ 1.2355 + pgl_cluster *query = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2356 + /* return true if estimated distance (allowed to be smaller than real 1.2357 + distance) between index key and circle center is smaller than radius */ 1.2358 + retval = ( 1.2359 + pgl_estimate_key_distance(key, &(query->bounding.center)) <= 1.2360 + query->bounding.radius 1.2361 + ); 1.2362 + PG_FREE_IF_COPY(query, 1); /* free detoasted cluster (if copy) */ 1.2363 + PG_RETURN_BOOL(retval); 1.2364 + } 1.2365 + /* throw error for any unknown strategy number */ 1.2366 + elog(ERROR, "unrecognized strategy number: %d", strategy); 1.2367 +} 1.2368 + 1.2369 +/* GiST "union" support function */ 1.2370 +PG_FUNCTION_INFO_V1(pgl_gist_union); 1.2371 +Datum pgl_gist_union(PG_FUNCTION_ARGS) { 1.2372 + GistEntryVector *entryvec = (GistEntryVector *)PG_GETARG_POINTER(0); 1.2373 + pgl_keyptr out; /* return value (to be palloc'ed) */ 1.2374 + int i; 1.2375 + /* determine key size */ 1.2376 + size_t keysize = PGL_KEY_IS_AREAKEY( 1.2377 + (pgl_keyptr)DatumGetPointer(entryvec->vector[0].key) 1.2378 + ) ? sizeof (pgl_areakey) : sizeof(pgl_pointkey); 1.2379 + /* begin with first key as result */ 1.2380 + out = palloc(keysize); 1.2381 + memcpy(out, (pgl_keyptr)DatumGetPointer(entryvec->vector[0].key), keysize); 1.2382 + /* unite current result with second, third, etc. key */ 1.2383 + for (i=1; i<entryvec->n; i++) { 1.2384 + pgl_unite_keys(out, (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key)); 1.2385 + } 1.2386 + /* return result */ 1.2387 + PG_RETURN_POINTER(out); 1.2388 +} 1.2389 + 1.2390 +/* GiST "compress" support function for indicis on points */ 1.2391 +PG_FUNCTION_INFO_V1(pgl_gist_compress_epoint); 1.2392 +Datum pgl_gist_compress_epoint(PG_FUNCTION_ARGS) { 1.2393 + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); 1.2394 + GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */ 1.2395 + /* only transform new leaves */ 1.2396 + if (entry->leafkey) { 1.2397 + /* get point to be transformed */ 1.2398 + pgl_point *point = (pgl_point *)DatumGetPointer(entry->key); 1.2399 + /* allocate memory for key */ 1.2400 + pgl_keyptr key = palloc(sizeof(pgl_pointkey)); 1.2401 + /* transform point to key */ 1.2402 + pgl_point_to_key(point, key); 1.2403 + /* create new GISTENTRY structure as return value */ 1.2404 + retval = palloc(sizeof(GISTENTRY)); 1.2405 + gistentryinit( 1.2406 + *retval, PointerGetDatum(key), 1.2407 + entry->rel, entry->page, entry->offset, FALSE 1.2408 + ); 1.2409 + } else { 1.2410 + /* inner nodes have already been transformed */ 1.2411 + retval = entry; 1.2412 + } 1.2413 + /* return pointer to old or new GISTENTRY structure */ 1.2414 + PG_RETURN_POINTER(retval); 1.2415 +} 1.2416 + 1.2417 +/* GiST "compress" support function for indicis on circles */ 1.2418 +PG_FUNCTION_INFO_V1(pgl_gist_compress_ecircle); 1.2419 +Datum pgl_gist_compress_ecircle(PG_FUNCTION_ARGS) { 1.2420 + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); 1.2421 + GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */ 1.2422 + /* only transform new leaves */ 1.2423 + if (entry->leafkey) { 1.2424 + /* get circle to be transformed */ 1.2425 + pgl_circle *circle = (pgl_circle *)DatumGetPointer(entry->key); 1.2426 + /* allocate memory for key */ 1.2427 + pgl_keyptr key = palloc(sizeof(pgl_areakey)); 1.2428 + /* transform circle to key */ 1.2429 + pgl_circle_to_key(circle, key); 1.2430 + /* create new GISTENTRY structure as return value */ 1.2431 + retval = palloc(sizeof(GISTENTRY)); 1.2432 + gistentryinit( 1.2433 + *retval, PointerGetDatum(key), 1.2434 + entry->rel, entry->page, entry->offset, FALSE 1.2435 + ); 1.2436 + } else { 1.2437 + /* inner nodes have already been transformed */ 1.2438 + retval = entry; 1.2439 + } 1.2440 + /* return pointer to old or new GISTENTRY structure */ 1.2441 + PG_RETURN_POINTER(retval); 1.2442 +} 1.2443 + 1.2444 +/* GiST "compress" support function for indices on clusters */ 1.2445 +PG_FUNCTION_INFO_V1(pgl_gist_compress_ecluster); 1.2446 +Datum pgl_gist_compress_ecluster(PG_FUNCTION_ARGS) { 1.2447 + GISTENTRY *entry = (GISTENTRY *) PG_GETARG_POINTER(0); 1.2448 + GISTENTRY *retval; /* return value (to be palloc'ed unless set to entry) */ 1.2449 + /* only transform new leaves */ 1.2450 + if (entry->leafkey) { 1.2451 + /* get cluster to be transformed (detoasting necessary!) */ 1.2452 + pgl_cluster *cluster = (pgl_cluster *)PG_DETOAST_DATUM(entry->key); 1.2453 + /* allocate memory for key */ 1.2454 + pgl_keyptr key = palloc(sizeof(pgl_areakey)); 1.2455 + /* transform cluster to key */ 1.2456 + pgl_circle_to_key(&(cluster->bounding), key); 1.2457 + /* create new GISTENTRY structure as return value */ 1.2458 + retval = palloc(sizeof(GISTENTRY)); 1.2459 + gistentryinit( 1.2460 + *retval, PointerGetDatum(key), 1.2461 + entry->rel, entry->page, entry->offset, FALSE 1.2462 + ); 1.2463 + /* free detoasted datum */ 1.2464 + if ((void *)cluster != (void *)DatumGetPointer(entry->key)) pfree(cluster); 1.2465 + } else { 1.2466 + /* inner nodes have already been transformed */ 1.2467 + retval = entry; 1.2468 + } 1.2469 + /* return pointer to old or new GISTENTRY structure */ 1.2470 + PG_RETURN_POINTER(retval); 1.2471 +} 1.2472 + 1.2473 +/* GiST "decompress" support function for indices */ 1.2474 +PG_FUNCTION_INFO_V1(pgl_gist_decompress); 1.2475 +Datum pgl_gist_decompress(PG_FUNCTION_ARGS) { 1.2476 + /* return passed pointer without transformation */ 1.2477 + PG_RETURN_POINTER(PG_GETARG_POINTER(0)); 1.2478 +} 1.2479 + 1.2480 +/* GiST "penalty" support function */ 1.2481 +PG_FUNCTION_INFO_V1(pgl_gist_penalty); 1.2482 +Datum pgl_gist_penalty(PG_FUNCTION_ARGS) { 1.2483 + GISTENTRY *origentry = (GISTENTRY *)PG_GETARG_POINTER(0); 1.2484 + GISTENTRY *newentry = (GISTENTRY *)PG_GETARG_POINTER(1); 1.2485 + float *penalty = (float *)PG_GETARG_POINTER(2); 1.2486 + /* get original key and key to insert */ 1.2487 + pgl_keyptr orig = (pgl_keyptr)DatumGetPointer(origentry->key); 1.2488 + pgl_keyptr new = (pgl_keyptr)DatumGetPointer(newentry->key); 1.2489 + /* copy original key */ 1.2490 + union { pgl_pointkey pointkey; pgl_areakey areakey; } union_key; 1.2491 + if (PGL_KEY_IS_AREAKEY(orig)) { 1.2492 + memcpy(union_key.areakey, orig, sizeof(union_key.areakey)); 1.2493 + } else { 1.2494 + memcpy(union_key.pointkey, orig, sizeof(union_key.pointkey)); 1.2495 + } 1.2496 + /* calculate union of both keys */ 1.2497 + pgl_unite_keys((pgl_keyptr)&union_key, new); 1.2498 + /* penalty equal to reduction of key length (logarithm of added area) */ 1.2499 + /* (return value by setting referenced value and returning pointer) */ 1.2500 + *penalty = ( 1.2501 + PGL_KEY_NODEDEPTH(orig) - PGL_KEY_NODEDEPTH((pgl_keyptr)&union_key) 1.2502 + ); 1.2503 + PG_RETURN_POINTER(penalty); 1.2504 +} 1.2505 + 1.2506 +/* GiST "picksplit" support function */ 1.2507 +PG_FUNCTION_INFO_V1(pgl_gist_picksplit); 1.2508 +Datum pgl_gist_picksplit(PG_FUNCTION_ARGS) { 1.2509 + GistEntryVector *entryvec = (GistEntryVector *)PG_GETARG_POINTER(0); 1.2510 + GIST_SPLITVEC *v = (GIST_SPLITVEC *)PG_GETARG_POINTER(1); 1.2511 + OffsetNumber i; /* between FirstOffsetNumber and entryvec->n (inclusive) */ 1.2512 + union { 1.2513 + pgl_pointkey pointkey; 1.2514 + pgl_areakey areakey; 1.2515 + } union_all; /* union of all keys (to be calculated from scratch) 1.2516 + (later cut in half) */ 1.2517 + int is_areakey = PGL_KEY_IS_AREAKEY( 1.2518 + (pgl_keyptr)DatumGetPointer(entryvec->vector[FirstOffsetNumber].key) 1.2519 + ); 1.2520 + int keysize = is_areakey ? sizeof(pgl_areakey) : sizeof(pgl_pointkey); 1.2521 + pgl_keyptr unionL = palloc(keysize); /* union of keys that go left */ 1.2522 + pgl_keyptr unionR = palloc(keysize); /* union of keys that go right */ 1.2523 + pgl_keyptr key; /* current key to be processed */ 1.2524 + /* allocate memory for array of left and right keys, set counts to zero */ 1.2525 + v->spl_left = (OffsetNumber *)palloc(entryvec->n * sizeof(OffsetNumber)); 1.2526 + v->spl_nleft = 0; 1.2527 + v->spl_right = (OffsetNumber *)palloc(entryvec->n * sizeof(OffsetNumber)); 1.2528 + v->spl_nright = 0; 1.2529 + /* calculate union of all keys from scratch */ 1.2530 + memcpy( 1.2531 + (pgl_keyptr)&union_all, 1.2532 + (pgl_keyptr)DatumGetPointer(entryvec->vector[FirstOffsetNumber].key), 1.2533 + keysize 1.2534 + ); 1.2535 + for (i=FirstOffsetNumber+1; i<entryvec->n; i=OffsetNumberNext(i)) { 1.2536 + pgl_unite_keys( 1.2537 + (pgl_keyptr)&union_all, 1.2538 + (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key) 1.2539 + ); 1.2540 + } 1.2541 + /* check if trivial split is necessary due to exhausted key length */ 1.2542 + /* (Note: keys for empty objects must have node depth set to maximum) */ 1.2543 + if (PGL_KEY_NODEDEPTH((pgl_keyptr)&union_all) == ( 1.2544 + is_areakey ? PGL_AREAKEY_MAXDEPTH : PGL_POINTKEY_MAXDEPTH 1.2545 + )) { 1.2546 + /* half of all keys go left */ 1.2547 + for ( 1.2548 + i=FirstOffsetNumber; 1.2549 + i<FirstOffsetNumber+(entryvec->n - FirstOffsetNumber)/2; 1.2550 + i=OffsetNumberNext(i) 1.2551 + ) { 1.2552 + /* pointer to current key */ 1.2553 + key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key); 1.2554 + /* update unionL */ 1.2555 + /* check if key is first key that goes left */ 1.2556 + if (!v->spl_nleft) { 1.2557 + /* first key that goes left is just copied to unionL */ 1.2558 + memcpy(unionL, key, keysize); 1.2559 + } else { 1.2560 + /* unite current value and next key */ 1.2561 + pgl_unite_keys(unionL, key); 1.2562 + } 1.2563 + /* append offset number to list of keys that go left */ 1.2564 + v->spl_left[v->spl_nleft++] = i; 1.2565 + } 1.2566 + /* other half goes right */ 1.2567 + for ( 1.2568 + i=FirstOffsetNumber+(entryvec->n - FirstOffsetNumber)/2; 1.2569 + i<entryvec->n; 1.2570 + i=OffsetNumberNext(i) 1.2571 + ) { 1.2572 + /* pointer to current key */ 1.2573 + key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key); 1.2574 + /* update unionR */ 1.2575 + /* check if key is first key that goes right */ 1.2576 + if (!v->spl_nright) { 1.2577 + /* first key that goes right is just copied to unionR */ 1.2578 + memcpy(unionR, key, keysize); 1.2579 + } else { 1.2580 + /* unite current value and next key */ 1.2581 + pgl_unite_keys(unionR, key); 1.2582 + } 1.2583 + /* append offset number to list of keys that go right */ 1.2584 + v->spl_right[v->spl_nright++] = i; 1.2585 + } 1.2586 + } 1.2587 + /* otherwise, a non-trivial split is possible */ 1.2588 + else { 1.2589 + /* cut covered area in half */ 1.2590 + /* (union_all then refers to area of keys that go left) */ 1.2591 + /* check if union of all keys covers empty and non-empty objects */ 1.2592 + if (PGL_KEY_IS_UNIVERSAL((pgl_keyptr)&union_all)) { 1.2593 + /* if yes, split into empty and non-empty objects */ 1.2594 + pgl_key_set_empty((pgl_keyptr)&union_all); 1.2595 + } else { 1.2596 + /* otherwise split by next bit */ 1.2597 + ((pgl_keyptr)&union_all)[PGL_KEY_NODEDEPTH_OFFSET]++; 1.2598 + /* NOTE: type bit conserved */ 1.2599 + } 1.2600 + /* determine for each key if it goes left or right */ 1.2601 + for (i=FirstOffsetNumber; i<entryvec->n; i=OffsetNumberNext(i)) { 1.2602 + /* pointer to current key */ 1.2603 + key = (pgl_keyptr)DatumGetPointer(entryvec->vector[i].key); 1.2604 + /* keys within one half of the area go left */ 1.2605 + if (pgl_keys_overlap((pgl_keyptr)&union_all, key)) { 1.2606 + /* update unionL */ 1.2607 + /* check if key is first key that goes left */ 1.2608 + if (!v->spl_nleft) { 1.2609 + /* first key that goes left is just copied to unionL */ 1.2610 + memcpy(unionL, key, keysize); 1.2611 + } else { 1.2612 + /* unite current value of unionL and processed key */ 1.2613 + pgl_unite_keys(unionL, key); 1.2614 + } 1.2615 + /* append offset number to list of keys that go left */ 1.2616 + v->spl_left[v->spl_nleft++] = i; 1.2617 + } 1.2618 + /* the other keys go right */ 1.2619 + else { 1.2620 + /* update unionR */ 1.2621 + /* check if key is first key that goes right */ 1.2622 + if (!v->spl_nright) { 1.2623 + /* first key that goes right is just copied to unionR */ 1.2624 + memcpy(unionR, key, keysize); 1.2625 + } else { 1.2626 + /* unite current value of unionR and processed key */ 1.2627 + pgl_unite_keys(unionR, key); 1.2628 + } 1.2629 + /* append offset number to list of keys that go right */ 1.2630 + v->spl_right[v->spl_nright++] = i; 1.2631 + } 1.2632 + } 1.2633 + } 1.2634 + /* store unions in return value */ 1.2635 + v->spl_ldatum = PointerGetDatum(unionL); 1.2636 + v->spl_rdatum = PointerGetDatum(unionR); 1.2637 + /* return all results */ 1.2638 + PG_RETURN_POINTER(v); 1.2639 +} 1.2640 + 1.2641 +/* GiST "same"/"equal" support function */ 1.2642 +PG_FUNCTION_INFO_V1(pgl_gist_same); 1.2643 +Datum pgl_gist_same(PG_FUNCTION_ARGS) { 1.2644 + pgl_keyptr key1 = (pgl_keyptr)PG_GETARG_POINTER(0); 1.2645 + pgl_keyptr key2 = (pgl_keyptr)PG_GETARG_POINTER(1); 1.2646 + bool *boolptr = (bool *)PG_GETARG_POINTER(2); 1.2647 + /* two keys are equal if they are binary equal */ 1.2648 + /* (return result by setting referenced boolean and returning pointer) */ 1.2649 + *boolptr = !memcmp( 1.2650 + key1, 1.2651 + key2, 1.2652 + PGL_KEY_IS_AREAKEY(key1) ? sizeof(pgl_areakey) : sizeof(pgl_pointkey) 1.2653 + ); 1.2654 + PG_RETURN_POINTER(boolptr); 1.2655 +} 1.2656 + 1.2657 +/* GiST "distance" support function */ 1.2658 +PG_FUNCTION_INFO_V1(pgl_gist_distance); 1.2659 +Datum pgl_gist_distance(PG_FUNCTION_ARGS) { 1.2660 + GISTENTRY *entry = (GISTENTRY *)PG_GETARG_POINTER(0); 1.2661 + pgl_keyptr key = (pgl_keyptr)DatumGetPointer(entry->key); 1.2662 + StrategyNumber strategy = (StrategyNumber)PG_GETARG_UINT16(2); 1.2663 + bool *recheck = (bool *)PG_GETARG_POINTER(4); 1.2664 + double distance; /* return value */ 1.2665 + /* demand recheck because distance is just an estimation */ 1.2666 + /* (real distance may be bigger) */ 1.2667 + *recheck = true; 1.2668 + /* strategy number 31: distance to point */ 1.2669 + if (strategy == 31) { 1.2670 + /* query datum is a point */ 1.2671 + pgl_point *query = (pgl_point *)PG_GETARG_POINTER(1); 1.2672 + /* use pgl_estimate_pointkey_distance() function to compute result */ 1.2673 + distance = pgl_estimate_key_distance(key, query); 1.2674 + /* avoid infinity (reserved!) */ 1.2675 + if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE; 1.2676 + /* return result */ 1.2677 + PG_RETURN_FLOAT8(distance); 1.2678 + } 1.2679 + /* strategy number 33: distance to circle */ 1.2680 + if (strategy == 33) { 1.2681 + /* query datum is a circle */ 1.2682 + pgl_circle *query = (pgl_circle *)PG_GETARG_POINTER(1); 1.2683 + /* estimate distance to circle center and substract circle radius */ 1.2684 + distance = ( 1.2685 + pgl_estimate_key_distance(key, &(query->center)) - query->radius 1.2686 + ); 1.2687 + /* convert non-positive values to zero and avoid infinity (reserved!) */ 1.2688 + if (distance <= 0) distance = 0; 1.2689 + else if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE; 1.2690 + /* return result */ 1.2691 + PG_RETURN_FLOAT8(distance); 1.2692 + } 1.2693 + /* strategy number 34: distance to cluster */ 1.2694 + if (strategy == 34) { 1.2695 + /* query datum is a cluster */ 1.2696 + pgl_cluster *query = (pgl_cluster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); 1.2697 + /* estimate distance to bounding center and substract bounding radius */ 1.2698 + distance = ( 1.2699 + pgl_estimate_key_distance(key, &(query->bounding.center)) - 1.2700 + query->bounding.radius 1.2701 + ); 1.2702 + /* convert non-positive values to zero and avoid infinity (reserved!) */ 1.2703 + if (distance <= 0) distance = 0; 1.2704 + else if (!isfinite(distance)) distance = PGL_ULTRA_DISTANCE; 1.2705 + /* free detoasted cluster (if copy) */ 1.2706 + PG_FREE_IF_COPY(query, 1); 1.2707 + /* return result */ 1.2708 + PG_RETURN_FLOAT8(distance); 1.2709 + } 1.2710 + /* throw error for any unknown strategy number */ 1.2711 + elog(ERROR, "unrecognized strategy number: %d", strategy); 1.2712 +} 1.2713 +