From 08f331e6b07b28d057f713a13c66cb64e585d6b4 Mon Sep 17 00:00:00 2001
From: Paul Ramsey <pramsey@cleverelephant.ca>
Date: Tue, 31 Jan 2012 18:19:36 +0000
Subject: [PATCH] ST_SnapToGrid returns a value out of range (#1292)

git-svn-id: http://svn.osgeo.org/postgis/trunk@8980 b70326c6-7e19-0410-871a-916f4a2858ee
---
 liblwgeom/liblwgeom.h.in  |   5 ++
 liblwgeom/lwgeodetic.c    | 101 ++++++++++++++++++++++++++++++++++++++
 postgis/geography_inout.c |  18 ++++---
 3 files changed, 118 insertions(+), 6 deletions(-)

diff --git a/liblwgeom/liblwgeom.h.in b/liblwgeom/liblwgeom.h.in
index c8d226f6c..ce1fcdfe1 100644
--- a/liblwgeom/liblwgeom.h.in
+++ b/liblwgeom/liblwgeom.h.in
@@ -1437,6 +1437,11 @@ extern GSERIALIZED* gserialized_copy(const GSERIALIZED *g);
 */
 extern int lwgeom_check_geodetic(const LWGEOM *geom);
 
+/**
+* Check that coordinates of LWGEOM are all within the geodetic range.
+*/
+extern int lwgeom_nudge_geodetic(LWGEOM *geom);
+
 /**
 * Set the FLAGS geodetic bit on geometry an all sub-geometries and pointlists
 */
diff --git a/liblwgeom/lwgeodetic.c b/liblwgeom/lwgeodetic.c
index 83d7db663..0db9d4893 100644
--- a/liblwgeom/lwgeodetic.c
+++ b/liblwgeom/lwgeodetic.c
@@ -2653,3 +2653,104 @@ double lwgeom_length_spheroid(const LWGEOM *geom, const SPHEROID *s)
 	lwerror("unsupported type passed to lwgeom_length_sphere");
 	return 0.0;
 }
+
+/**
+* When features are snapped or sometimes they are just this way, they are very close to 
+* the geodetic bounds but slightly over. This routine nudges those points, and only
+* those points, back over to the bounds.
+* http://trac.osgeo.org/postgis/ticket/1292
+*/
+int ptarray_nudge_geodetic(POINTARRAY *pa)
+{
+	int i;
+	POINT4D p;
+	int altered = LW_FALSE;
+	int rv = LW_FALSE;
+	static double tolerance = 1e-10;
+	if ( ! pa ) return;
+	for(i = 0; i < pa->npoints; i++ )
+	{
+		getPoint4d_p(pa, i, &p);
+		if ( p.x < -180.0 && (-180.0 - p.x < tolerance) )
+		{
+			p.x = -180.0;
+			altered = LW_TRUE;
+		}
+		else if ( p.x > 180.0 && (p.x - 180.0 < tolerance) )
+		{
+			p.x = 180.0;
+			altered = LW_TRUE;
+		}
+		else if ( p.y < -90.0 && (-90.0 - p.y < tolerance) )
+		{
+			p.y = -90.0;
+			altered = LW_TRUE;
+		}
+		else if ( p.y > 90.0 && (p.y - 90.0 < tolerance) )
+		{
+			p.y = 90.0;
+			altered = LW_TRUE;
+		}
+		if ( altered == LW_TRUE )
+		{
+			ptarray_set_point4d(pa, i, &p);
+			altered = LW_FALSE;
+			rv = LW_TRUE;
+		}
+	}
+	return rv;
+}
+
+/**
+* When features are snapped or sometimes they are just this way, they are very close to 
+* the geodetic bounds but slightly over. This routine nudges those points, and only
+* those points, back over to the bounds.
+* http://trac.osgeo.org/postgis/ticket/1292
+*/
+int lwgeom_nudge_geodetic(LWGEOM *geom)
+{
+	int type;
+	int i = 0;
+	int rv = LW_FALSE;
+
+	assert(geom);
+
+	/* No points in nothing */
+	if ( lwgeom_is_empty(geom) )
+		return LW_FALSE;
+
+	type = geom->type;
+
+	if ( type == POINTTYPE )
+		return ptarray_nudge_geodetic(((LWPOINT*)geom)->point);
+
+	if ( type == LINETYPE )
+		return ptarray_nudge_geodetic(((LWLINE*)geom)->points);
+
+	if ( type == POLYGONTYPE )
+	{
+		LWPOLY *poly = (LWPOLY*)geom;
+		for ( i = 0; i < poly->nrings; i++ )
+		{
+			rv = (rv == LW_TRUE ? rv : ptarray_nudge_geodetic(poly->rings[i]));
+		}
+		return rv;
+	}
+
+	if ( type == TRIANGLETYPE )
+		return ptarray_nudge_geodetic(((LWTRIANGLE*)geom)->points);
+
+	if ( lwtype_is_collection( type ) )
+	{
+		LWCOLLECTION *col = (LWCOLLECTION*)geom;
+
+		for ( i = 0; i < col->ngeoms; i++ )
+		{
+			rv = (rv == LW_TRUE ? rv : ptarray_nudge_geodetic(col->geoms[i]));
+		}
+		return rv;
+	}
+
+	lwerror("unsupported type (%s) passed to lwgeom_nudge_geodetic", lwtype_name(type));
+	return rv;
+}
\ No newline at end of file
diff --git a/postgis/geography_inout.c b/postgis/geography_inout.c
index f710dc416..d121a4b21 100644
--- a/postgis/geography_inout.c
+++ b/postgis/geography_inout.c
@@ -87,9 +87,12 @@ GSERIALIZED* gserialized_geography_from_lwgeom(LWGEOM *lwgeom, int32 geog_typmod
 	/* Check that the coordinates are in range */
 	if ( lwgeom_check_geodetic(lwgeom) == LW_FALSE )
 	{
-		ereport(ERROR, (
-		            errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-		            errmsg("Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY type" )));
+		if ( (! lwgeom_nudge_geodetic(lwgeom)) || lwgeom_check_geodetic(lwgeom) == LW_FALSE )
+		{
+			ereport(ERROR, (
+			        errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+			        errmsg("Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY type" )));
+		}
 	}
 
 	/* Force default SRID to the default */
@@ -562,9 +565,12 @@ Datum geography_from_geometry(PG_FUNCTION_ARGS)
 	/* Check if the geography has valid coordinate range. */
 	if ( lwgeom_check_geodetic(lwgeom) == LW_FALSE )
 	{
-		ereport(ERROR, (
-		            errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-		            errmsg("Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY type" )));
+		if ( (! lwgeom_nudge_geodetic(lwgeom)) || lwgeom_check_geodetic(lwgeom) == LW_FALSE )
+		{
+			ereport(ERROR, (
+			        errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+			        errmsg("Coordinate values are out of range [-180 -90, 180 90] for GEOGRAPHY type" )));
+		}
 	}
 
 	/*
-- 
2.40.0