Add point_ops opclass for GiST.

src/backend/access/gist/gistproc.c

@@ -10,7 +10,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	$PostgreSQL: pgsql/src/backend/access/gist/gistproc.c,v 1.19 2010/01/02 16:57:34 momjian Exp $
+ *	$PostgreSQL: pgsql/src/backend/access/gist/gistproc.c,v 1.20 2010/01/14 16:31:09 teodor Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -165,7 +165,8 @@ gist_box_compress(PG_FUNCTION_ARGS)
 }
 
 /*
- * GiST DeCompress method for boxes (also used for polygons and circles)
+ * GiST DeCompress method for boxes (also used for points, polygons
+ * and circles)
  *
  * do not do anything --- we just use the stored box as is.
  */
@@ -176,7 +177,7 @@ gist_box_decompress(PG_FUNCTION_ARGS)
 }
 
 /*
- * The GiST Penalty method for boxes
+ * The GiST Penalty method for boxes (also used for points)
  *
  * As in the R-tree paper, we use change in area as our penalty metric
  */
@@ -341,6 +342,8 @@ fallbackSplit(GistEntryVector *entryvec, GIST_SPLITVEC *v)
  *
  * New linear algorithm, see 'New Linear Node Splitting Algorithm for R-tree',
  * C.H.Ang and T.C.Tan
+ *
+ * This is used for both boxes and points.
  */
 Datum
 gist_box_picksplit(PG_FUNCTION_ARGS)
@@ -533,6 +536,8 @@ gist_box_picksplit(PG_FUNCTION_ARGS)
 
 /*
  * Equality method
+ *
+ * This is used for both boxes and points.
  */
 Datum
 gist_box_same(PG_FUNCTION_ARGS)
@@ -872,3 +877,166 @@ gist_circle_consistent(PG_FUNCTION_ARGS)
 
 	PG_RETURN_BOOL(result);
 }
+
+/**************************************************
+ * Point ops
+ **************************************************/
+
+Datum
+gist_point_compress(PG_FUNCTION_ARGS)
+{
+	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+
+	if (entry->leafkey)			/* Point, actually */
+	{
+		BOX	   *box = palloc(sizeof(BOX));
+		Point  *point = DatumGetPointP(entry->key);
+		GISTENTRY  *retval = palloc(sizeof(GISTENTRY));
+
+		box->high = box->low = *point;
+
+		gistentryinit(*retval, BoxPGetDatum(box),
+					  entry->rel, entry->page, entry->offset, FALSE);
+
+		PG_RETURN_POINTER(retval);
+	}
+
+	PG_RETURN_POINTER(entry);
+}
+
+static bool
+gist_point_consistent_internal(StrategyNumber strategy,
+										   bool isLeaf, BOX *key, Point *query)
+{
+	bool result = false;
+
+	switch (strategy)
+	{
+		case RTLeftStrategyNumber:
+			result = FPlt(key->low.x, query->x);
+			break;
+		case RTRightStrategyNumber:
+			result = FPgt(key->high.x, query->x);
+			break;
+		case RTAboveStrategyNumber:
+			result = FPgt(key->high.y, query->y);
+			break;
+		case RTBelowStrategyNumber:
+			result = FPlt(key->low.y, query->y);
+			break;
+		case RTSameStrategyNumber:
+			if (isLeaf)
+			{
+				result = FPeq(key->low.x, query->x)
+					&& FPeq(key->low.y, query->y);
+			}
+			else
+			{
+				result = (query->x <= key->high.x && query->x >= key->low.x &&
+						  query->y <= key->high.y && query->y >= key->low.y);
+			}
+			break;
+		default:
+			elog(ERROR, "unknown strategy number: %d", strategy);
+	}
+
+	return result;
+}
+
+#define GeoStrategyNumberOffset		20
+#define PointStrategyNumberGroup	0
+#define BoxStrategyNumberGroup		1
+#define PolygonStrategyNumberGroup	2
+#define CircleStrategyNumberGroup	3
+
+Datum
+gist_point_consistent(PG_FUNCTION_ARGS)
+{
+	GISTENTRY  *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
+	StrategyNumber	strategy = (StrategyNumber) PG_GETARG_UINT16(2);
+	bool		result;
+	bool	   *recheck = (bool *) PG_GETARG_POINTER(4);
+	StrategyNumber	strategyGroup = strategy / GeoStrategyNumberOffset;
+
+	switch (strategyGroup)
+	{
+		case PointStrategyNumberGroup:
+			result = gist_point_consistent_internal(strategy % GeoStrategyNumberOffset,
+													GIST_LEAF(entry),
+													DatumGetBoxP(entry->key),
+													PG_GETARG_POINT_P(1));
+			*recheck = false;
+			break;
+		case BoxStrategyNumberGroup:
+			result = DatumGetBool(DirectFunctionCall5(
+											gist_box_consistent,
+											PointerGetDatum(entry),
+											PG_GETARG_DATUM(1),
+											Int16GetDatum(RTOverlapStrategyNumber),
+											0, PointerGetDatum(recheck)));
+			break;
+		case PolygonStrategyNumberGroup:
+			{
+				POLYGON    *query = PG_GETARG_POLYGON_P(1);
+
+				result = DatumGetBool(DirectFunctionCall5(
+												gist_poly_consistent,
+												PointerGetDatum(entry),
+												PolygonPGetDatum(query),
+												Int16GetDatum(RTOverlapStrategyNumber),
+												0, PointerGetDatum(recheck)));
+
+				if (GIST_LEAF(entry) && result)
+				{
+					/*
+					 * We are on leaf page and quick check shows overlapping
+					 * of polygon's bounding box and point
+					 */
+					BOX *box = DatumGetBoxP(entry->key);
+
+					Assert(box->high.x == box->low.x
+						&& box->high.y == box->low.y);
+					result = DatumGetBool(DirectFunctionCall2(
+												poly_contain_pt,
+												PolygonPGetDatum(query),
+												PointPGetDatum(&box->high)));
+					*recheck = false;
+				}
+			}
+			break;
+		case CircleStrategyNumberGroup:
+			{
+				CIRCLE *query = PG_GETARG_CIRCLE_P(1);
+
+				result = DatumGetBool(DirectFunctionCall5(
+												gist_circle_consistent,
+												PointerGetDatum(entry),
+												CirclePGetDatum(query),
+												Int16GetDatum(RTOverlapStrategyNumber),
+												0, PointerGetDatum(recheck)));
+
+				if (GIST_LEAF(entry) && result)
+				{
+					/*
+					 * We are on leaf page and quick check shows overlapping
+					 * of polygon's bounding box and point
+					 */
+					BOX *box = DatumGetBoxP(entry->key);
+
+					Assert(box->high.x == box->low.x
+						&& box->high.y == box->low.y);
+					result = DatumGetBool(DirectFunctionCall2(
+												circle_contain_pt,
+												CirclePGetDatum(query),
+												PointPGetDatum(&box->high)));
+					*recheck = false;
+				}
+			}
+			break;
+		default:
+			result = false;			/* silence compiler warning */
+			elog(ERROR, "unknown strategy number: %d", strategy);
+	}
+
+	PG_RETURN_BOOL(result);
+}