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docs/lib-vorono3d.md

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+# voronoi
+
+Creats a three version of [Voronoi diagram](https://en.wikipedia.org/wiki/Voronoi_diagram). The initial space for each cell is calculated automatically from the given points by the following code: 
+
+    xs = [for(p = points) p[0]];
+    ys = [for(p = points) abs(p[1])];
+    zs = [for(p = points) abs(p[2])];
+    space_size = max([(max(xs) -  min(xs) / 2), (max(ys) -  min(ys)) / 2, (max(zs) -  min(zs)) / 2]);
+
+The preview or rendering of 3D Voronoi is slow. If you want to use this module, render and export the 3D Voronoi model first. Then, `import` the model to do what you want.
+
+**Since:** 1.3.
+
+## Parameters
+
+- `points` : Points for each cell. 
+- `spacing` : Distance between cells. Default to 1.
+- `space_type` : The initial space for each cell can be `"cube"` or `"sphere"`. Default to `"cube"`.
+
+## Examples
+
+    include <voronoi3d.scad>;
+
+    r = 30;
+
+    zas = rands(0, 359, 12);
+    yas = rands(0, 179, 12);
+
+    points = [
+        for(i = [0:len(zas) - 1])
+        [
+            r * cos(yas[i]) * cos(zas[i]), 
+            r * cos(yas[i]) * sin(zas[i]), 
+            r * sin(yas[i])
+        ]
+    ];
+
+    #for(pt = points) {
+        translate(pt) cube(1);
+    }
+
+![voronoi](images/lib-voronoi3d-1.JPG)
+
+    If you render, export and save the previous model as `voronoi3d.stl`, the following code will generate a Voronoi sphere.
+
+    r = 30;
+    thickness = 2;
+
+    difference() {
+        sphere(r);
+        scale(1.01) import("voronoi3d.stl");
+        sphere(r - thickness);
+    }
+    
+![voronoi](images/lib-voronoi3d-2.JPG)