1 files changed, 88 insertions, 9 deletions

diff --git a/src/backend/utils/adt/geo_spgist.c b/src/backend/utils/adt/geo_spgist.c
index f9e8db63ddc..e52d80f5e13 100644
--- a/src/backend/utils/adt/geo_spgist.c
+++ b/src/backend/utils/adt/geo_spgist.c
@@ -74,9 +74,11 @@
 #include "postgres.h"
 
 #include "access/spgist.h"
+#include "access/spgist_private.h"
 #include "access/stratnum.h"
 #include "catalog/pg_type.h"
 #include "utils/float.h"
+#include "utils/fmgroids.h"
 #include "utils/fmgrprotos.h"
 #include "utils/geo_decls.h"
 
@@ -367,6 +369,31 @@ overAbove4D(RectBox *rect_box, RangeBox *query)
 	return overHigher2D(&rect_box->range_box_y, &query->right);
 }
 
+/* Lower bound for the distance between point and rect_box */
+static double
+pointToRectBoxDistance(Point *point, RectBox *rect_box)
+{
+	double		dx;
+	double		dy;
+
+	if (point->x < rect_box->range_box_x.left.low)
+		dx = rect_box->range_box_x.left.low - point->x;
+	else if (point->x > rect_box->range_box_x.right.high)
+		dx = point->x - rect_box->range_box_x.right.high;
+	else
+		dx = 0;
+
+	if (point->y < rect_box->range_box_y.left.low)
+		dy = rect_box->range_box_y.left.low - point->y;
+	else if (point->y > rect_box->range_box_y.right.high)
+		dy = point->y - rect_box->range_box_y.right.high;
+	else
+		dy = 0;
+
+	return HYPOT(dx, dy);
+}
+
+
 /*
  * SP-GiST config function
  */
@@ -534,6 +561,15 @@ spg_box_quad_inner_consistent(PG_FUNCTION_ARGS)
 	RangeBox   *centroid,
 			  **queries;
 
+	/*
+	 * We are saving the traversal value or initialize it an unbounded one, if
+	 * we have just begun to walk the tree.
+	 */
+	if (in->traversalValue)
+		rect_box = in->traversalValue;
+	else
+		rect_box = initRectBox();
+
 	if (in->allTheSame)
 	{
 		/* Report that all nodes should be visited */
@@ -542,19 +578,33 @@ spg_box_quad_inner_consistent(PG_FUNCTION_ARGS)
 		for (i = 0; i < in->nNodes; i++)
 			out->nodeNumbers[i] = i;
 
+		if (in->norderbys > 0 && in->nNodes > 0)
+		{
+			double	   *distances = palloc(sizeof(double) * in->norderbys);
+			int			j;
+
+			for (j = 0; j < in->norderbys; j++)
+			{
+				Point	   *pt = DatumGetPointP(in->orderbys[j].sk_argument);
+
+				distances[j] = pointToRectBoxDistance(pt, rect_box);
+			}
+
+			out->distances = (double **) palloc(sizeof(double *) * in->nNodes);
+			out->distances[0] = distances;
+
+			for (i = 1; i < in->nNodes; i++)
+			{
+				out->distances[i] = palloc(sizeof(double) * in->norderbys);
+				memcpy(out->distances[i], distances,
+					   sizeof(double) * in->norderbys);
+			}
+		}
+
 		PG_RETURN_VOID();
 	}
 
 	/*
-	 * We are saving the traversal value or initialize it an unbounded one, if
-	 * we have just begun to walk the tree.
-	 */
-	if (in->traversalValue)
-		rect_box = in->traversalValue;
-	else
-		rect_box = initRectBox();
-
-	/*
 	 * We are casting the prefix and queries to RangeBoxes for ease of the
 	 * following operations.
 	 */
@@ -571,6 +621,8 @@ spg_box_quad_inner_consistent(PG_FUNCTION_ARGS)
 	out->nNodes = 0;
 	out->nodeNumbers = (int *) palloc(sizeof(int) * in->nNodes);
 	out->traversalValues = (void **) palloc(sizeof(void *) * in->nNodes);
+	if (in->norderbys > 0)
+		out->distances = (double **) palloc(sizeof(double *) * in->nNodes);
 
 	/*
 	 * We switch memory context, because we want to allocate memory for new
@@ -648,6 +700,22 @@ spg_box_quad_inner_consistent(PG_FUNCTION_ARGS)
 		{
 			out->traversalValues[out->nNodes] = next_rect_box;
 			out->nodeNumbers[out->nNodes] = quadrant;
+
+			if (in->norderbys > 0)
+			{
+				double	   *distances = palloc(sizeof(double) * in->norderbys);
+				int			j;
+
+				out->distances[out->nNodes] = distances;
+
+				for (j = 0; j < in->norderbys; j++)
+				{
+					Point	   *pt = DatumGetPointP(in->orderbys[j].sk_argument);
+
+					distances[j] = pointToRectBoxDistance(pt, next_rect_box);
+				}
+			}
+
 			out->nNodes++;
 		}
 		else
@@ -763,6 +831,17 @@ spg_box_quad_leaf_consistent(PG_FUNCTION_ARGS)
 			break;
 	}
 
+	if (flag && in->norderbys > 0)
+	{
+		Oid			distfnoid = in->orderbys[0].sk_func.fn_oid;
+
+		out->distances = spg_key_orderbys_distances(leaf, false,
+													in->orderbys, in->norderbys);
+
+		/* Recheck is necessary when computing distance to polygon */
+		out->recheckDistances = distfnoid == F_DIST_POLYP;
+	}
+
 	PG_RETURN_BOOL(flag);
 }