diff --git a/pgsql_postgis/pointcloud_postgis--1.0.sql b/pgsql_postgis/pointcloud_postgis--1.0.sql
index ea96725..34bd5fd 100644
--- a/pgsql_postgis/pointcloud_postgis--1.0.sql
+++ b/pgsql_postgis/pointcloud_postgis--1.0.sql
@@ -23,8 +23,16 @@ CREATE OR REPLACE FUNCTION PC_Envelope(pcpatch)
 	$$
 	LANGUAGE 'sql';
 
+CREATE OR REPLACE FUNCTION geometry(pcpatch)
+	RETURNS geometry AS
+	$$
+		SELECT PC_Envelope($1)
+	$$
+	LANGUAGE 'sql';
+
 CREATE CAST (pcpatch AS geometry) WITH FUNCTION PC_Envelope(pcpatch);
 
+
 -----------------------------------------------------------------------------
 -- Cast from pcpoint to point
 --