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DROP TABLE IF EXISTS raster_pixelaspolygons;
CREATE TABLE raster_pixelaspolygons (
rast raster
);
CREATE OR REPLACE FUNCTION make_test_raster()
RETURNS void
AS $$
DECLARE
width int := 10;
height int := 10;
x int;
y int;
rast raster;
BEGIN
rast := ST_MakeEmptyRaster(width, height, 0, 0, 1, -1, 0, 0, 0);
rast := ST_AddBand(rast, 1, '32BUI', 0, 0);
FOR x IN 1..width LOOP
FOR y IN 1..height LOOP
IF (x + y) % 2 = 1 THEN
rast := ST_SetValue(rast, 1, x, y, x + y);
END IF;
END LOOP;
END LOOP;
INSERT INTO raster_pixelaspolygons VALUES (rast);
RETURN;
END;
$$ LANGUAGE 'plpgsql';
SELECT make_test_raster();
DROP FUNCTION make_test_raster();
SELECT
(pix).x,
(pix).y,
(pix).val,
ST_AsText((pix).geom)
FROM (SELECT ST_PixelAsPolygons(rast) AS pix FROM raster_pixelaspolygons) foo
ORDER BY 1, 2, 4;
SELECT
(pix).x,
(pix).y,
(pix).val,
ST_AsText((pix).geom)
FROM (SELECT ST_PixelAsPolygons(ST_SetBandNoDataValue(rast, NULL)) AS pix FROM raster_pixelaspolygons) foo
ORDER BY 1, 2, 4;
SELECT
(pix).x,
(pix).y,
(pix).val,
ST_AsText((pix).geom)
FROM (SELECT ST_PixelAsPolygons(rast, NULL) AS pix FROM raster_pixelaspolygons) foo
ORDER BY 1, 2, 4;
SELECT
(pix).x,
(pix).y,
(pix).val,
ST_AsText((pix).geom)
FROM (SELECT ST_PixelAsPolygons(rast, 1, FALSE) AS pix FROM raster_pixelaspolygons) foo
ORDER BY 1, 2, 4;
SELECT ST_AsText(ST_PixelAsPolygon(rast, 1, 1)) FROM raster_pixelaspolygons;
SELECT ST_AsText(ST_PixelAsPolygon(rast, 1, 2)) FROM raster_pixelaspolygons;
SELECT ST_AsText(ST_PixelAsPolygon(rast, -1, -1)) FROM raster_pixelaspolygons;
DROP TABLE IF EXISTS raster_pixelaspolygons;
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