grid_for_bounding_box.sql

CREATE OR REPLACE FUNCTION ST_GridFromBbox(
    IN x0 double precision,
    IN y0 double precision,
    IN x1 double precision,
    IN y1 double precision,
    IN xsize double precision,
    IN ysize double precision,
    OUT "row" integer,
    OUT col integer,
    OUT geom geometry)
  RETURNS SETOF record AS
$BODY$
SELECT i + 1 AS row, j + 1 AS col, ST_Translate(cell, j * $5 + $1, i * $6 + $2) AS geom
FROM generate_series(0, abs(ceil(($3 - $1)) / $5)::integer - 1) AS i,
     generate_series(0, abs(ceil(($4 - $2)) / $6)::integer - 1) AS j,
(
SELECT ('POLYGON((0 0, 0 '||$6||', '||$5||' '||$6||', '||$5||' 0,0 0))')::geometry AS cell
) AS foo;
$BODY$
  LANGUAGE sql IMMUTABLE STRICT;