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docs/lib2x-nz_worley2s.md

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+# nz_worley2s
+
+Returns 2D [Worley noise](https://en.wikipedia.org/wiki/Worley_noise) values `[cell_x, cell_y, noise]` at (x, y) coordinates. 
+
+It divides the space into tiles. The nucleus of each cell is randomly placed in a tile. 
+
+![nz_worley2s](images/lib2x-nz_worley2s-1.JPG)
+
+**Since:** 2.3
+
+## Parameters
+
+- `points` :  A list of `[x, y]` coordinates.
+- `seed` :  The random seed. If it's ignored, a randomized value will be used.
+- `tile_w` : The tile width. Default to 10. Smaller `tile_w` makes more cells.
+- `dist` : The noise value of each point is based on its distance to other cells. Different distance strategies make different noises. The `dist` parameter accepts `"euclidean"`, `"manhattan"`, `"chebyshev"` or `"border"`.
+
+## Examples
+
+    use <noise/nz_worley2s.scad>;
+
+    size = [100, 50];
+    tile_w = 10;
+    dist = "euclidean"; // [euclidean, manhattan, chebyshev, border] 
+    seed = 51;
+
+    points = [
+        for(y = [0:size[1] - 1]) 
+            for(x = [0:size[0] - 1]) 
+                [x, y]
+    ];
+
+    cells = nz_worley2s(points, seed, tile_w, dist);
+
+    for(i = [0:len(cells) - 1]) {
+        h = norm([cells[i][0], cells[i][1]]) % 10;
+        color([h, h, h] / 10)
+        linear_extrude(h)
+        translate(points[i])
+            square(1);
+    }
+
+![nz_worley2s](images/lib2x-nz_worley2s-2.JPG)