diff options
Diffstat (limited to 'src/backend/access/spgist/spgquadtreeproc.c')
-rw-r--r-- | src/backend/access/spgist/spgquadtreeproc.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/src/backend/access/spgist/spgquadtreeproc.c b/src/backend/access/spgist/spgquadtreeproc.c new file mode 100644 index 0000000..ce6464f --- /dev/null +++ b/src/backend/access/spgist/spgquadtreeproc.c @@ -0,0 +1,471 @@ +/*------------------------------------------------------------------------- + * + * spgquadtreeproc.c + * implementation of quad tree over points for SP-GiST + * + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/backend/access/spgist/spgquadtreeproc.c + * + *------------------------------------------------------------------------- + */ + +#include "postgres.h" + +#include "access/spgist.h" +#include "access/spgist_private.h" +#include "access/stratnum.h" +#include "catalog/pg_type.h" +#include "utils/builtins.h" +#include "utils/float.h" +#include "utils/geo_decls.h" + +Datum +spg_quad_config(PG_FUNCTION_ARGS) +{ + /* spgConfigIn *cfgin = (spgConfigIn *) PG_GETARG_POINTER(0); */ + spgConfigOut *cfg = (spgConfigOut *) PG_GETARG_POINTER(1); + + cfg->prefixType = POINTOID; + cfg->labelType = VOIDOID; /* we don't need node labels */ + cfg->canReturnData = true; + cfg->longValuesOK = false; + PG_RETURN_VOID(); +} + +#define SPTEST(f, x, y) \ + DatumGetBool(DirectFunctionCall2(f, PointPGetDatum(x), PointPGetDatum(y))) + +/* + * Determine which quadrant a point falls into, relative to the centroid. + * + * Quadrants are identified like this: + * + * 4 | 1 + * ----+----- + * 3 | 2 + * + * Points on one of the axes are taken to lie in the lowest-numbered + * adjacent quadrant. + */ +static int16 +getQuadrant(Point *centroid, Point *tst) +{ + if ((SPTEST(point_above, tst, centroid) || + SPTEST(point_horiz, tst, centroid)) && + (SPTEST(point_right, tst, centroid) || + SPTEST(point_vert, tst, centroid))) + return 1; + + if (SPTEST(point_below, tst, centroid) && + (SPTEST(point_right, tst, centroid) || + SPTEST(point_vert, tst, centroid))) + return 2; + + if ((SPTEST(point_below, tst, centroid) || + SPTEST(point_horiz, tst, centroid)) && + SPTEST(point_left, tst, centroid)) + return 3; + + if (SPTEST(point_above, tst, centroid) && + SPTEST(point_left, tst, centroid)) + return 4; + + elog(ERROR, "getQuadrant: impossible case"); + return 0; +} + +/* Returns bounding box of a given quadrant inside given bounding box */ +static BOX * +getQuadrantArea(BOX *bbox, Point *centroid, int quadrant) +{ + BOX *result = (BOX *) palloc(sizeof(BOX)); + + switch (quadrant) + { + case 1: + result->high = bbox->high; + result->low = *centroid; + break; + case 2: + result->high.x = bbox->high.x; + result->high.y = centroid->y; + result->low.x = centroid->x; + result->low.y = bbox->low.y; + break; + case 3: + result->high = *centroid; + result->low = bbox->low; + break; + case 4: + result->high.x = centroid->x; + result->high.y = bbox->high.y; + result->low.x = bbox->low.x; + result->low.y = centroid->y; + break; + } + + return result; +} + +Datum +spg_quad_choose(PG_FUNCTION_ARGS) +{ + spgChooseIn *in = (spgChooseIn *) PG_GETARG_POINTER(0); + spgChooseOut *out = (spgChooseOut *) PG_GETARG_POINTER(1); + Point *inPoint = DatumGetPointP(in->datum), + *centroid; + + if (in->allTheSame) + { + out->resultType = spgMatchNode; + /* nodeN will be set by core */ + out->result.matchNode.levelAdd = 0; + out->result.matchNode.restDatum = PointPGetDatum(inPoint); + PG_RETURN_VOID(); + } + + Assert(in->hasPrefix); + centroid = DatumGetPointP(in->prefixDatum); + + Assert(in->nNodes == 4); + + out->resultType = spgMatchNode; + out->result.matchNode.nodeN = getQuadrant(centroid, inPoint) - 1; + out->result.matchNode.levelAdd = 0; + out->result.matchNode.restDatum = PointPGetDatum(inPoint); + + PG_RETURN_VOID(); +} + +#ifdef USE_MEDIAN +static int +x_cmp(const void *a, const void *b, void *arg) +{ + Point *pa = *(Point **) a; + Point *pb = *(Point **) b; + + if (pa->x == pb->x) + return 0; + return (pa->x > pb->x) ? 1 : -1; +} + +static int +y_cmp(const void *a, const void *b, void *arg) +{ + Point *pa = *(Point **) a; + Point *pb = *(Point **) b; + + if (pa->y == pb->y) + return 0; + return (pa->y > pb->y) ? 1 : -1; +} +#endif + +Datum +spg_quad_picksplit(PG_FUNCTION_ARGS) +{ + spgPickSplitIn *in = (spgPickSplitIn *) PG_GETARG_POINTER(0); + spgPickSplitOut *out = (spgPickSplitOut *) PG_GETARG_POINTER(1); + int i; + Point *centroid; + +#ifdef USE_MEDIAN + /* Use the median values of x and y as the centroid point */ + Point **sorted; + + sorted = palloc(sizeof(*sorted) * in->nTuples); + for (i = 0; i < in->nTuples; i++) + sorted[i] = DatumGetPointP(in->datums[i]); + + centroid = palloc(sizeof(*centroid)); + + qsort(sorted, in->nTuples, sizeof(*sorted), x_cmp); + centroid->x = sorted[in->nTuples >> 1]->x; + qsort(sorted, in->nTuples, sizeof(*sorted), y_cmp); + centroid->y = sorted[in->nTuples >> 1]->y; +#else + /* Use the average values of x and y as the centroid point */ + centroid = palloc0(sizeof(*centroid)); + + for (i = 0; i < in->nTuples; i++) + { + centroid->x += DatumGetPointP(in->datums[i])->x; + centroid->y += DatumGetPointP(in->datums[i])->y; + } + + centroid->x /= in->nTuples; + centroid->y /= in->nTuples; +#endif + + out->hasPrefix = true; + out->prefixDatum = PointPGetDatum(centroid); + + out->nNodes = 4; + out->nodeLabels = NULL; /* we don't need node labels */ + + out->mapTuplesToNodes = palloc(sizeof(int) * in->nTuples); + out->leafTupleDatums = palloc(sizeof(Datum) * in->nTuples); + + for (i = 0; i < in->nTuples; i++) + { + Point *p = DatumGetPointP(in->datums[i]); + int quadrant = getQuadrant(centroid, p) - 1; + + out->leafTupleDatums[i] = PointPGetDatum(p); + out->mapTuplesToNodes[i] = quadrant; + } + + PG_RETURN_VOID(); +} + + +Datum +spg_quad_inner_consistent(PG_FUNCTION_ARGS) +{ + spgInnerConsistentIn *in = (spgInnerConsistentIn *) PG_GETARG_POINTER(0); + spgInnerConsistentOut *out = (spgInnerConsistentOut *) PG_GETARG_POINTER(1); + Point *centroid; + BOX infbbox; + BOX *bbox = NULL; + int which; + int i; + + Assert(in->hasPrefix); + centroid = DatumGetPointP(in->prefixDatum); + + /* + * When ordering scan keys are specified, we've to calculate distance for + * them. In order to do that, we need calculate bounding boxes for all + * children nodes. Calculation of those bounding boxes on non-zero level + * require knowledge of bounding box of upper node. So, we save bounding + * boxes to traversalValues. + */ + if (in->norderbys > 0) + { + out->distances = (double **) palloc(sizeof(double *) * in->nNodes); + out->traversalValues = (void **) palloc(sizeof(void *) * in->nNodes); + + if (in->level == 0) + { + double inf = get_float8_infinity(); + + infbbox.high.x = inf; + infbbox.high.y = inf; + infbbox.low.x = -inf; + infbbox.low.y = -inf; + bbox = &infbbox; + } + else + { + bbox = in->traversalValue; + Assert(bbox); + } + } + + if (in->allTheSame) + { + /* Report that all nodes should be visited */ + out->nNodes = in->nNodes; + out->nodeNumbers = (int *) palloc(sizeof(int) * in->nNodes); + for (i = 0; i < in->nNodes; i++) + { + out->nodeNumbers[i] = i; + + if (in->norderbys > 0) + { + MemoryContext oldCtx = MemoryContextSwitchTo(in->traversalMemoryContext); + + /* Use parent quadrant box as traversalValue */ + BOX *quadrant = box_copy(bbox); + + MemoryContextSwitchTo(oldCtx); + + out->traversalValues[i] = quadrant; + out->distances[i] = spg_key_orderbys_distances(BoxPGetDatum(quadrant), false, + in->orderbys, in->norderbys); + } + } + PG_RETURN_VOID(); + } + + Assert(in->nNodes == 4); + + /* "which" is a bitmask of quadrants that satisfy all constraints */ + which = (1 << 1) | (1 << 2) | (1 << 3) | (1 << 4); + + for (i = 0; i < in->nkeys; i++) + { + Point *query = DatumGetPointP(in->scankeys[i].sk_argument); + BOX *boxQuery; + + switch (in->scankeys[i].sk_strategy) + { + case RTLeftStrategyNumber: + if (SPTEST(point_right, centroid, query)) + which &= (1 << 3) | (1 << 4); + break; + case RTRightStrategyNumber: + if (SPTEST(point_left, centroid, query)) + which &= (1 << 1) | (1 << 2); + break; + case RTSameStrategyNumber: + which &= (1 << getQuadrant(centroid, query)); + break; + case RTBelowStrategyNumber: + case RTOldBelowStrategyNumber: + if (SPTEST(point_above, centroid, query)) + which &= (1 << 2) | (1 << 3); + break; + case RTAboveStrategyNumber: + case RTOldAboveStrategyNumber: + if (SPTEST(point_below, centroid, query)) + which &= (1 << 1) | (1 << 4); + break; + case RTContainedByStrategyNumber: + + /* + * For this operator, the query is a box not a point. We + * cheat to the extent of assuming that DatumGetPointP won't + * do anything that would be bad for a pointer-to-box. + */ + boxQuery = DatumGetBoxP(in->scankeys[i].sk_argument); + + if (DatumGetBool(DirectFunctionCall2(box_contain_pt, + PointerGetDatum(boxQuery), + PointerGetDatum(centroid)))) + { + /* centroid is in box, so all quadrants are OK */ + } + else + { + /* identify quadrant(s) containing all corners of box */ + Point p; + int r = 0; + + p = boxQuery->low; + r |= 1 << getQuadrant(centroid, &p); + p.y = boxQuery->high.y; + r |= 1 << getQuadrant(centroid, &p); + p = boxQuery->high; + r |= 1 << getQuadrant(centroid, &p); + p.x = boxQuery->low.x; + r |= 1 << getQuadrant(centroid, &p); + + which &= r; + } + break; + default: + elog(ERROR, "unrecognized strategy number: %d", + in->scankeys[i].sk_strategy); + break; + } + + if (which == 0) + break; /* no need to consider remaining conditions */ + } + + out->levelAdds = palloc(sizeof(int) * 4); + for (i = 0; i < 4; ++i) + out->levelAdds[i] = 1; + + /* We must descend into the quadrant(s) identified by which */ + out->nodeNumbers = (int *) palloc(sizeof(int) * 4); + out->nNodes = 0; + + for (i = 1; i <= 4; i++) + { + if (which & (1 << i)) + { + out->nodeNumbers[out->nNodes] = i - 1; + + if (in->norderbys > 0) + { + MemoryContext oldCtx = MemoryContextSwitchTo(in->traversalMemoryContext); + BOX *quadrant = getQuadrantArea(bbox, centroid, i); + + MemoryContextSwitchTo(oldCtx); + + out->traversalValues[out->nNodes] = quadrant; + + out->distances[out->nNodes] = spg_key_orderbys_distances(BoxPGetDatum(quadrant), false, + in->orderbys, in->norderbys); + } + + out->nNodes++; + } + } + + PG_RETURN_VOID(); +} + + +Datum +spg_quad_leaf_consistent(PG_FUNCTION_ARGS) +{ + spgLeafConsistentIn *in = (spgLeafConsistentIn *) PG_GETARG_POINTER(0); + spgLeafConsistentOut *out = (spgLeafConsistentOut *) PG_GETARG_POINTER(1); + Point *datum = DatumGetPointP(in->leafDatum); + bool res; + int i; + + /* all tests are exact */ + out->recheck = false; + + /* leafDatum is what it is... */ + out->leafValue = in->leafDatum; + + /* Perform the required comparison(s) */ + res = true; + for (i = 0; i < in->nkeys; i++) + { + Point *query = DatumGetPointP(in->scankeys[i].sk_argument); + + switch (in->scankeys[i].sk_strategy) + { + case RTLeftStrategyNumber: + res = SPTEST(point_left, datum, query); + break; + case RTRightStrategyNumber: + res = SPTEST(point_right, datum, query); + break; + case RTSameStrategyNumber: + res = SPTEST(point_eq, datum, query); + break; + case RTBelowStrategyNumber: + case RTOldBelowStrategyNumber: + res = SPTEST(point_below, datum, query); + break; + case RTAboveStrategyNumber: + case RTOldAboveStrategyNumber: + res = SPTEST(point_above, datum, query); + break; + case RTContainedByStrategyNumber: + + /* + * For this operator, the query is a box not a point. We + * cheat to the extent of assuming that DatumGetPointP won't + * do anything that would be bad for a pointer-to-box. + */ + res = SPTEST(box_contain_pt, query, datum); + break; + default: + elog(ERROR, "unrecognized strategy number: %d", + in->scankeys[i].sk_strategy); + break; + } + + if (!res) + break; + } + + if (res && in->norderbys > 0) + /* ok, it passes -> let's compute the distances */ + out->distances = spg_key_orderbys_distances(in->leafDatum, true, + in->orderbys, in->norderbys); + + PG_RETURN_BOOL(res); +} |