Add generated images to dir + readme

1 files changed, 18 insertions, 0 deletions

diff --git a/src/circle.sql b/src/circle.sql
new file mode 100644
index 0000000..46874cc
--- /dev/null
+++ b/src/circle.sql
@@ -0,0 +1,18 @@
+DELETE FROM images WHERE id = 'circle';
+INSERT INTO images (id, width, height) VALUES ('circle', 200, 200) RETURNING id;
+
+WITH RECURSIVE
+  image AS (SELECT * FROM images WHERE id = 'circle'),
+  circle AS (SELECT width/2 AS cx, height/2 AS cy, 80 AS radius FROM image),
+  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),
+  _pixels(x, y, r, g, b) AS (SELECT
+    x, y,
+    150,
+    255 * MAX(0, MIN(1, (SELECT POW(x - cx, 2) + POW(y - cy, 2) - POW(radius, 2) FROM circle))),
+    150
+    FROM vertical, horizontal
+  )
+INSERT INTO pixels (image_id, x, y, r, g, b) SELECT 'circle', x, y, r, g, b FROM _pixels;