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INSERT OR REPLACE INTO images (id, width, height) VALUES ('voronoi', 400, 400) RETURNING id;
WITH RECURSIVE
image AS (SELECT *, 100 AS segments FROM images WHERE id = 'voronoi'),
horizontal(x) AS
(SELECT width FROM image UNION ALL SELECT x - 1 FROM horizontal WHERE x > 1),
vertical(y) AS
(SELECT height FROM image UNION ALL SELECT y - 1 FROM vertical WHERE y > 1),
points(px, py, count) AS (
SELECT 0, 0, 0 UNION ALL
SELECT abs(RANDOM())%width, abs(RANDOM())%height, count + 1 FROM points, image WHERE count < segments
),
_pixels(x, y, r, g, b) AS (
SELECT x, y,
0,
(SELECT color FROM
(SELECT (100*(px + 1)*(py + 1)) % 255 AS color,
POW(x - px, 2) + POW(y - py, 2) as distance
FROM points ORDER BY distance ASC LIMIT 1)),
40
FROM vertical, horizontal, image
)
INSERT INTO pixels (image_id, x, y, r, g, b) SELECT 'voronoi', x, y, r, g, b FROM _pixels;
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