From 9dde5f7da2256ea75c9231e839af5fe03947f6a1 Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@keybit.net>
Date: Tue, 7 Feb 2012 10:14:37 +0000
Subject: [PATCH] Allow changing a closed edge (but w/out fixing linking, see
 #892)

git-svn-id: http://svn.osgeo.org/postgis/trunk@9063 b70326c6-7e19-0410-871a-916f4a2858ee
---
 topology/sql/sqlmm.sql.in.c                   | 23 ++++++++++++++-----
 topology/test/regress/st_changeedgegeom.sql   |  5 +++-
 .../test/regress/st_changeedgegeom_expected   |  1 +
 3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/topology/sql/sqlmm.sql.in.c b/topology/sql/sqlmm.sql.in.c
index 6ab4ee3e7..8f8dfb93c 100644
--- a/topology/sql/sqlmm.sql.in.c
+++ b/topology/sql/sqlmm.sql.in.c
@@ -2605,14 +2605,18 @@ BEGIN
 
   --
   -- g) Check if curve crosses any node
-  -- _within_ used to let endpoints out
   -- 
-  FOR rec IN EXECUTE 'SELECT node_id FROM '
-    || quote_ident(atopology) || '.node
-    WHERE ST_Within(geom, ' || quote_literal(acurve::text) || '::geometry)'
+  FOR rec IN EXECUTE
+    'SELECT node_id, ST_Relate(geom, '
+    || quote_literal(acurve::text) || '::geometry, 2) as relate FROM '
+    || quote_ident(atopology)
+    || '.node WHERE geom && '
+    || quote_literal(acurve::text)
+    || '::geometry'
   LOOP
-    RAISE EXCEPTION
-    'SQL/MM Spatial exception - geometry crosses a node';
+    IF ST_RelateMatch(rec.relate, 'T********') THEN
+      RAISE EXCEPTION 'SQL/MM Spatial exception - geometry crosses a node';
+    END IF;
   END LOOP;
 
   --
@@ -2657,6 +2661,13 @@ BEGIN
     || ' SET geom = ' || quote_literal(acurve::text) 
     || ' WHERE edge_id = ' || anedge;
 
+  --
+  -- TODO: Check if we need to update linking
+  -- We do if:
+  --   o edge is closed and we changed direction)
+  --   o edge moved to another face
+  -- 
+
   RETURN 'Edge ' || anedge || ' changed';
 
 END
diff --git a/topology/test/regress/st_changeedgegeom.sql b/topology/test/regress/st_changeedgegeom.sql
index c0e2bcc57..d2278492f 100644
--- a/topology/test/regress/st_changeedgegeom.sql
+++ b/topology/test/regress/st_changeedgegeom.sql
@@ -33,7 +33,10 @@ SELECT topology.ST_ChangeEdgeGeom('city_data', 5,
 SELECT topology.ST_ChangeEdgeGeom('city_data', 5,
  'LINESTRING(41 40, 49 40, 49 34, 57 33)');
 
--- TODO: test changing closed edge
+-- Change a closed edge
+SELECT topology.ST_ChangeEdgeGeom('city_data', 26,
+ 'LINESTRING(4 31, 7 31, 4 34, 4 31)');
+
 -- TODO: test reverse direction of closed edge
 
 SELECT topology.DropTopology('city_data');
diff --git a/topology/test/regress/st_changeedgegeom_expected b/topology/test/regress/st_changeedgegeom_expected
index a6a94142c..3de3f8e57 100644
--- a/topology/test/regress/st_changeedgegeom_expected
+++ b/topology/test/regress/st_changeedgegeom_expected
@@ -12,4 +12,5 @@ ERROR:  SQL/MM Spatial exception - non-existent edge 666
 ERROR:  SQL/MM Spatial exception - geometry crosses an edge
 Edge 5 changed
 Edge 5 changed
+Edge 26 changed
 Topology 'city_data' dropped
-- 
2.40.0