[postgis-commits] svn - r3678 - spike/wktraster/rt_pg

[postgis-commits at postgis.refractions.net]

Author: strk
Date: 2009-02-10 03:25:51 -0800 (Tue, 10 Feb 2009)
New Revision: 3678

Modified:
   spike/wktraster/rt_pg/rt_pg.c
Log:
Implement rt_envelope (SQL)

Modified: spike/wktraster/rt_pg/rt_pg.c
===================================================================
--- spike/wktraster/rt_pg/rt_pg.c	2009-02-10 08:00:39 UTC (rev 3677)
+++ spike/wktraster/rt_pg/rt_pg.c	2009-02-10 11:25:51 UTC (rev 3678)
@@ -67,6 +67,7 @@
 Datum RASTER_in(PG_FUNCTION_ARGS);
 Datum RASTER_out(PG_FUNCTION_ARGS);
 Datum RASTER_to_BOX2DFLOAT4(PG_FUNCTION_ARGS);
+Datum RASTER_envelope(PG_FUNCTION_ARGS);
 Datum RASTER_makeEmpty(PG_FUNCTION_ARGS);
 
 Datum RASTER_to_LWGEOM(PG_FUNCTION_ARGS);
@@ -272,6 +273,49 @@
 }
 
 /**
+ * Return the envelope of this raster as a 4-vertices POLYGON.
+ */
+PG_FUNCTION_INFO_V1(RASTER_envelope);
+Datum RASTER_envelope(PG_FUNCTION_ARGS)
+{
+    rt_pgraster *pgraster = (rt_pgraster *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
+    rt_raster raster;
+    rt_context ctx = get_rt_context(fcinfo);
+    LWPOLY* envelope;
+    uchar* pglwgeom;
+
+    { /* TODO: can be optimized to only detoast the header! */
+        raster = rt_raster_deserialize(ctx, pgraster);
+        if ( ! raster ) {
+            elog(ERROR, "Could not deserialize raster");
+            PG_RETURN_NULL();
+        }
+
+        /*elog(NOTICE, "rt_raster_deserialize returned %p", raster);*/
+
+        envelope = rt_raster_get_envelope(ctx, raster);
+        if ( ! envelope ) {
+            elog(ERROR, "Could not get raster's envelope");
+            PG_RETURN_NULL();
+        }
+    }
+
+    {
+        size_t sz = lwpoly_serialize_size(envelope);
+        pglwgeom = palloc(VARHDRSZ+sz);
+        lwpoly_serialize_buf(envelope, VARDATA(pglwgeom), &sz);
+        SET_VARSIZE(pglwgeom, VARHDRSZ+sz);
+    }
+
+    /* PG_FREE_IF_COPY(pgraster, 0); */
+    /* lwfree(envelope) */
+    /* ... more deallocs ... */
+
+
+    PG_RETURN_POINTER(pglwgeom);
+}
+
+/**
  * Return the bounding box of this raster as a BOX2D.
  */
 PG_FUNCTION_INFO_V1(RASTER_to_BOX2DFLOAT4);