coverage_read_partition_into_collection()

static GEOSGeometry * coverage_read_partition_into_collection ( WindowObject  winobj, coverage_context *  context  )

static

Definition at line 519 of file lwgeom_window.c.

{
        int64 rowcount = WinGetPartitionRowCount(winobj);
        GEOSGeometry* geos;
        GEOSGeometry** geoms;
        uint32 i, ngeoms = 0, gtype;
 
        /* Read in all the geometries in this partition */
        geoms = palloc(rowcount * sizeof(GEOSGeometry*));
        for (i = 0; i < rowcount; i++)
        {
                GSERIALIZED* gser;
                bool isnull, isout;
                bool isempty, ispolygonal;
                Datum d;
 
                /* Read geometry in first argument */
                d = WinGetFuncArgInPartition(winobj, 0, i,
                                WINDOW_SEEK_HEAD, false, &isnull, &isout);
 
                /*
                 * The input to the GEOS function will be smaller than
                 * the input to this window, since we will not feed
                 * GEOS nulls or empties. So we need to maintain a
                 * map (context->idx) from the window position of the
                 * input to the GEOS position, so we can put the
                 * right result in the output stream. Things we want to
                 * skip get an index of -1.
                 */
 
                /* Skip NULL inputs and move on */
                if (isnull)
                {
                        context->idx[i] = -1;
                        continue;
                }
 
                gser = (GSERIALIZED*)PG_DETOAST_DATUM(d);
                gtype = gserialized_get_type(gser);
                isempty = gserialized_is_empty(gser);
                ispolygonal = (gtype == MULTIPOLYGONTYPE) || (gtype == POLYGONTYPE);
 
                /* Skip empty or non-polygonal inputs */
                if (isempty || !ispolygonal)
                {
                        context->idx[i] = -1;
                        continue;
                }
 
                /* Skip failed inputs */
                geos = POSTGIS2GEOS(gser);
                if (!geos)
                {
                        context->idx[i] = -1;
                        continue;
                }
 
                context->idx[i] = ngeoms;
                geoms[ngeoms] = geos;
                ngeoms = ngeoms + 1;
        }
 
        /*
         * Create the GEOS input collection! The new
         * collection takes ownership of the input GEOSGeometry
         * objects, leaving just the geoms array, which
         * will be cleaned up on function exit.
         */
        geos = GEOSGeom_createCollection(
                GEOS_GEOMETRYCOLLECTION,
                geoms, ngeoms);
 
        /*
         * If the creation failed, the objects will still be
         * hanging around, so clean them up first. Should
         * never happen, really.
         */
        if (!geos)
        {
                coverage_destroy_geoms(geoms, ngeoms);
                return NULL;
        }
 
        pfree(geoms);
        return geos;
}

References coverage_destroy_geoms(), gserialized_get_type(), gserialized_is_empty(), coverage_context::idx, MULTIPOLYGONTYPE, POLYGONTYPE, and POSTGIS2GEOS().

Referenced by coverage_window_calculation().

Here is the call graph for this function:

Here is the caller graph for this function: