GiST support

CHANGELOG.md

@@ -49,6 +49,7 @@ avoid adding features or APIs which do not map onto the
 - Use CMake for entire build (see [#70])
 - Add helper to fix pass-by-value migration (see [#111])
 - Allow distance operator `<->` to work for cells at different resolutions (using center child).
+- Add `gist` operator class (see [#42], thanks [@abelvm])
 
 ## [4.0.3] - 2022-11-04
 
@@ -241,6 +242,7 @@ avoid adding features or APIs which do not map onto the
 [#37]: https://github.com/zachasme/h3-pg/issues/37
 [#38]: https://github.com/zachasme/h3-pg/issues/38
 [#41]: https://github.com/zachasme/h3-pg/issues/41
+[#42]: https://github.com/zachasme/h3-pg/pull/42
 [#55]: https://github.com/zachasme/h3-pg/issues/55
 [#64]: https://github.com/zachasme/h3-pg/issues/64
 [#65]: https://github.com/zachasme/h3-pg/pull/65

docs/api.md

@@ -463,6 +463,30 @@ Returns true if A contains B.
 Returns true if A is contained by B.
 
 
+### h3index_gist_consistent(`internal`, `h3index`, `smallint`, `oid`, `internal`) ⇒ `boolean`
+
+
+### h3index_gist_union(`internal`, `internal`) ⇒ `h3index`
+
+
+### h3index_gist_compress(`internal`) ⇒ `internal`
+
+
+### h3index_gist_decompress(`internal`) ⇒ `internal`
+
+
+### h3index_gist_penalty(`internal`, `internal`, `internal`) ⇒ `internal`
+
+
+### h3index_gist_picksplit(`internal`, `internal`) ⇒ `internal`
+
+
+### h3index_gist_same(`h3index`, `h3index`, `internal`) ⇒ `internal`
+
+
+### h3index_gist_distance(`internal`, `h3index`, `smallint`, `oid`, `internal`) ⇒ `float8`
+
+
 # Type casts
 
 ### `h3index` :: `bigint`

h3/CMakeLists.txt

@@ -13,11 +13,13 @@ PostgreSQL_add_extension(postgresql_h3
     src/binding/regions.c
     src/binding/traversal.c
     src/binding/vertex.c
+    src/algos.c
     src/deprecated.c
     src/extension.c
     src/guc.c
     src/init.c
     src/opclass_btree.c
+    src/opclass_gist.c
     src/opclass_hash.c
     src/operators.c
     src/srf.c
@@ -36,6 +38,7 @@ PostgreSQL_add_extension(postgresql_h3
     sql/install/11-opclass_btree.sql
     sql/install/12-opclass_hash.sql
     sql/install/13-opclass_brin.sql
+    sql/install/14-opclass_gist.sql
     sql/install/20-casts.sql
     sql/install/30-extension.sql
     sql/install/99-deprecated.sql

h3/sql/install/14-opclass_gist.sql

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2019-2020 Bytes & Brains
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- ---------- ---------- ---------- ---------- ---------- ---------- ----------
+-- GiST Operator Class (opclass_gist.c)
+-- ---------- ---------- ---------- ---------- ---------- ---------- ----------
+
+CREATE OR REPLACE FUNCTION h3index_gist_consistent(internal, h3index, smallint, oid, internal) RETURNS boolean
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_union(internal, internal) RETURNS h3index
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_compress(internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_decompress(internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_penalty(internal, internal, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_picksplit(internal, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_same(h3index, h3index, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_distance(internal, h3index, smallint, oid, internal) RETURNS float8
+    AS 'h3' LANGUAGE C STRICT;
+
+CREATE OPERATOR CLASS experimental_h3index_ops FOR TYPE h3index USING gist AS
+    OPERATOR  3   &&  , -- RTOverlapStrategyNumber
+    OPERATOR  6   =   , -- RTSameStrategyNumber
+    OPERATOR  7   @>  , -- RTContainsStrategyNumber
+    OPERATOR  8   <@  , -- RTContainedByStrategyNumber
+    OPERATOR  15  <-> (h3index, h3index) FOR ORDER BY integer_ops,
+
+    FUNCTION  1  h3index_gist_consistent(internal, h3index, smallint, oid, internal),
+    FUNCTION  2  h3index_gist_union(internal, internal),
+--    FUNCTION  3  h3index_gist_compress(internal),
+--    FUNCTION  4  h3index_gist_decompress(internal),
+    FUNCTION  5  h3index_gist_penalty(internal, internal, internal),
+    FUNCTION  6  h3index_gist_picksplit(internal, internal),
+    FUNCTION  7  h3index_gist_same(h3index, h3index, internal),
+    FUNCTION  8  (h3index, h3index) h3index_gist_distance(internal, h3index, smallint, oid, internal);

h3/sql/updates/h3--4.1.3--unreleased.sql

@@ -16,3 +16,40 @@
 
 -- complain if script is sourced in psql, rather than via CREATE EXTENSION
 \echo Use "ALTER EXTENSION h3 UPDATE TO 'unreleased'" to load this file. \quit
+
+-- ---------- ---------- ---------- ---------- ---------- ---------- ----------
+-- GiST Operator Class (opclass_gist.c)
+-- ---------- ---------- ---------- ---------- ---------- ---------- ----------
+
+CREATE OR REPLACE FUNCTION h3index_gist_consistent(internal, h3index, smallint, oid, internal) RETURNS boolean
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_union(internal, internal) RETURNS h3index
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_compress(internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_decompress(internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_penalty(internal, internal, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_picksplit(internal, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_same(h3index, h3index, internal) RETURNS internal
+    AS 'h3' LANGUAGE C STRICT;
+CREATE OR REPLACE FUNCTION h3index_gist_distance(internal, h3index, smallint, oid, internal) RETURNS float8
+    AS 'h3' LANGUAGE C STRICT;
+
+CREATE OPERATOR CLASS experimental_h3index_ops FOR TYPE h3index USING gist AS
+    OPERATOR  3   &&  ,
+    OPERATOR  6   =   ,
+    OPERATOR  7   @>  ,
+    OPERATOR  8   <@  ,
+    OPERATOR  15  <-> (h3index, h3index) FOR ORDER BY integer_ops,
+
+    FUNCTION  1  h3index_gist_consistent(internal, h3index, smallint, oid, internal),
+    FUNCTION  2  h3index_gist_union(internal, internal),
+--    FUNCTION  3  h3index_gist_compress(internal),
+--    FUNCTION  4  h3index_gist_decompress(internal),
+    FUNCTION  5  h3index_gist_penalty(internal, internal, internal),
+    FUNCTION  6  h3index_gist_picksplit(internal, internal),
+    FUNCTION  7  h3index_gist_same(h3index, h3index, internal),
+    FUNCTION  8  (h3index, h3index) h3index_gist_distance(internal, h3index, smallint, oid, internal);

h3/src/algos.c

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2023 Bytes & Brains
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <h3api.h>
+#include "algos.h"
+#include "error.h"
+
+H3Index
+finest_common_ancestor(H3Index a, H3Index b)
+{
+	int			aRes,
+				bRes,
+				coarsestRes;
+	H3Index		aParent,
+				bParent;
+
+	if (a == b)
+		return a;
+
+	/* do not even share the basecell */
+	if (getBaseCellNumber(a) != getBaseCellNumber(b))
+		return H3_NULL;
+
+	aRes = getResolution(a);
+	bRes = getResolution(b);
+	coarsestRes = (aRes < bRes) ? aRes : bRes;
+
+	/* iterate backwards through resolutions */
+	for (int i = coarsestRes; i > 0; i--)
+	{
+		h3_assert(cellToParent(a, i, &aParent));
+		h3_assert(cellToParent(b, i, &bParent));
+		if (aParent == bParent)
+			return aParent;
+	}
+
+	return H3_NULL;
+}

h3/src/algos.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2023 Bytes & Brains
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *	   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef H3_ALGOS_H
+#define H3_ALGOS_H
+
+#include <h3api.h>
+
+H3Index finest_common_ancestor(H3Index, H3Index);
+
+#endif /* H3_ALGOS_H */