Commit bb73e661 authored by Darafei Praliaskouski's avatar Darafei Praliaskouski
Browse files

GEOS ClipByBox2D stub notice now includes ticket link 

Closes #4039
Closes https://github.com/postgis/postgis/pull/239


git-svn-id: http://svn.osgeo.org/postgis/trunk@16552 b70326c6-7e19-0410-871a-916f4a2858ee
parent 8739497f

doc/reference_processing.xml

+12 −12
Original line number Diff line number Diff line
@@ -490,16 +490,16 @@ FROM (SELECT ST_Buffer( 
		<title>Description</title>



    <para>

Clips a geometry by a 2D box in a fast but possibly dirty way. The output

geometry is not guaranteed to be valid (self-intersections for a polygon

may be introduced). Topologically invalid input geometries do not result

in exceptions being thrown.

Clips a geometry by a 2D box. The output geometry is not guaranteed to be valid

(self-intersections for a polygon may be introduced).

Topologically invalid input geometries do not result in exceptions being thrown.

    </para>



		<para>Performed by the GEOS module.</para>

		<note><para>Requires GEOS 3.5.0+</para></note>



		<para>Availability: 2.2.0 - requires GEOS &gt;= 3.5.0.</para>

		<para>Changed: 2.5.0 - wrapper around ST_Intersection to work around GEOS bugs. </para>



	  </refsection>

liblwgeom/lwgeom_geos.c

+7 −27
Original line number Diff line number Diff line
@@ -884,8 +884,14 @@ lwgeom_clip_by_rect(const LWGEOM *geom1, double x1, double y1, double x2, double 
{

	LWGEOM *result;

	LWGEOM *tmp;

	LWGEOM *envelope = (LWGEOM*)lwpoly_construct_envelope(geom1->srid, x1, y1, x2, y2);



	/* This lwgeom_intersection should be a call to GEOSClipByRect:

	 * g3 = GEOSClipByRect(g1, x1, y1, x2, y2);

	 * Unfortunately as of GEOS 3.7 it chokes on practical inputs.

	 * GEOS ticket: https://trac.osgeo.org/geos/ticket/865

	 */



	LWGEOM *envelope = (LWGEOM *)lwpoly_construct_envelope(geom1->srid, x1, y1, x2, y2);

	result = lwgeom_intersection(geom1, envelope);

	lwgeom_free(envelope);
@@ -908,32 +914,6 @@ lwgeom_clip_by_rect(const LWGEOM *geom1, double x1, double y1, double x2, double 
	lwgeom_simplify_in_place(result, 0.0, LW_TRUE);



	return result;



#if 0  /* POSTGIS_GEOS_VERSION >= 35, enable only after bugs in geos are fixed */

	int32_t srid = get_result_srid(geom, NULL, __func__);

	uint8_t is3d = FLAGS_GET_Z(geom->flags);

	GEOSGeometry *g1, *g3;



	if (srid == SRID_INVALID) return NULL;



	/* A.Intersection(Empty) == Empty */

	if (lwgeom_is_empty(geom)) return lwgeom_clone_deep(geom);



	initGEOS(lwnotice, lwgeom_geos_error);



	if (!input_lwgeom_to_geos(&g1, geom, __func__)) return NULL;



	g3 = GEOSClipByRect(g1, x1, y1, x2, y2);



	if (!g3) return geos_clean_and_fail(g1, NULL, NULL, __func__);



	if (!output_geos_as_lwgeom(&g3, &result, srid, is3d, __func__))

		return geos_clean_and_fail(g1, NULL, g3, __func__);



	geos_clean(g1, NULL, g3);



	return result;

#endif /* POSTGIS_GEOS_VERSION >= 35 */

}



/* ------------ BuildArea stuff ---------------------------------------------------------------------{ */