WITH pixels AS (
    SELECT
        col,
        row,
        x,
        y,
        (((x - 48.0)^2 / (25.0^2) + (y - 54.0)^2 / (29.0^2) < 1)
         OR ((x - 72.0)^2 / (25.0^2) + (y - 54.0)^2 / (29.0^2) < 1))
         AND NOT ((x - 60.0)^2 / (8.0^2) + (y - 26.0)^2 / (5.0^2) < 1) AS fruit,
        ((x - 82.0) * 0.84 + (y - 28.0) * 0.54)^2 / (22.0^2)
          + (-(x - 82.0) * 0.54 + (y - 28.0) * 0.84)^2 / (8.0^2) < 1 AS leaf,
        abs((x - 62.0) * 0.96 - (y - 29.0) * 0.28) < 3
          AND x BETWEEN 60 AND 69 AND y BETWEEN 21 AND 45 AS stem
    FROM (
        SELECT
            col,
            row,
            col / 2.0 AS x,
            row / 2.0 AS y
        FROM generate_series(1, 180) AS row
        CROSS JOIN generate_series(1, 240) AS col
    ) AS source_pixels
), shaded AS (
    SELECT
        col,
        row,
        x,
        y,
        CASE
            WHEN stem THEN 95 + y * 0.7 + (x % 3) * 8
            WHEN leaf THEN 28 + (90 - x) * 0.5
            WHEN fruit THEN LEAST(255, GREATEST(0,
                150
                + (85 - sqrt((x - 39.0)^2 + (y - 37.0)^2)) * 1.1
                + CASE
                    WHEN (x - 43.0)^2 / (10.0^2) + (y - 43.0)^2 / (7.0^2) < 1
                    THEN 35
                    ELSE 0
                END
                - CASE
                    WHEN (x - 77.0)^2 / (20.0^2) + (y - 67.0)^2 / (13.0^2) < 1
                    THEN 35
                    ELSE 0
                END
                + ((x * 13 + y * 7) % 19 - 9)
            ))
            ELSE 245
        END AS red,
        CASE
            WHEN stem THEN 50 + y * 0.35
            WHEN leaf THEN LEAST(190, GREATEST(40,
                105 + (95 - x) * 1.2 + (y - 20) * 1.5
                + CASE
                    WHEN (x - 76.0)^2 / (12.0^2) + (y - 24.0)^2 / (4.0^2) < 1
                    THEN 45
                    ELSE 0
                END
            ))
            WHEN fruit THEN LEAST(95, GREATEST(15,
                24 + (68 - y) * 0.35
                + CASE
                    WHEN (x - 43.0)^2 / (10.0^2) + (y - 43.0)^2 / (7.0^2) < 1
                    THEN 30
                    ELSE 0
                END
                + ((x * 5 + y * 11) % 13 - 6)
            ))
            ELSE 245
        END AS green,
        CASE
            WHEN stem THEN 22 + (x % 4) * 3
            WHEN leaf THEN 42 + (100 - x) * 0.4
            WHEN fruit THEN LEAST(75, GREATEST(10,
                18
                + CASE
                    WHEN (x - 43.0)^2 / (10.0^2) + (y - 43.0)^2 / (7.0^2) < 1
                    THEN 25
                    ELSE 0
                END
                + ((x * 3 + y * 5) % 11 - 5)
            ))
            ELSE 245
        END AS blue
    FROM pixels
), rows AS (
    SELECT
        row,
        array_agg(red::double precision ORDER BY col) AS red_values,
        array_agg(green::double precision ORDER BY col) AS green_values,
        array_agg(blue::double precision ORDER BY col) AS blue_values
    FROM shaded
    GROUP BY row
), source AS (
    SELECT ST_SetValues(ST_SetValues(ST_SetValues(
        ST_AddBand(ST_AddBand(ST_AddBand(
            ST_MakeEmptyRaster(240, 180, 0, 180, 1, -1, 0, 0, 0),
            '8BUI'::text, 245::double precision, 0::double precision),
            '8BUI'::text, 245::double precision, 0::double precision),
            '8BUI'::text, 245::double precision, 0::double precision),
        1, 1, 1, array_agg(red_values ORDER BY row)::double precision[][]),
        2, 1, 1, array_agg(green_values ORDER BY row)::double precision[][]),
        3, 1, 1, array_agg(blue_values ORDER BY row)::double precision[][]) AS rast
    FROM rows
)
SELECT ST_AsPNG(rast) AS "original RGB",
    ST_AsPNG(ST_Grayscale(rast)) AS "grayscale (variant 1)",
    ST_AsPNG(ST_Grayscale(ARRAY[
        ROW(rast, 1)::rastbandarg,
        ROW(rast, 2)::rastbandarg,
        ROW(rast, 3)::rastbandarg
    ]::rastbandarg[])) AS "grayscale (variant 2)"
FROM source;