add doc

README.md

@@ -237,7 +237,7 @@ These examples incubate dotSCAD and dotSCAD refactors these examples. See [examp
 
 - [curve](https://openhome.cc/eGossip/OpenSCAD/lib2x-curve.html)
 - [bauer_spiral](https://openhome.cc/eGossip/OpenSCAD/lib2x-bauer_spiral.html)
-- fibonacci_lattice
+- [fibonacci_lattice](https://openhome.cc/eGossip/OpenSCAD/lib2x-fibonacci_lattice.html)
 
 ### Voxel
 

docs/lib2x-fibonacci_lattice.md

@@ -0,0 +1,53 @@
+# fibonacci_lattice
+
+Creates visually even spacing of n points on the surface of the sphere. Nearest-neighbor points will all be approximately the same distance apart. There're 10 spirals on the sphere.
+
+(It's called "visually even spacing" because only the vertices of the 5 [Platonic solids](https://en.wikipedia.org/wiki/Platonic_solid) can be said to be truly evenly spaced around the surface of a sphere.)
+
+## Parameters
+
+- `n` : The number of points.
+- `radius` : The sphere radius. Default to 1.
+- `rt_dir` : `"CT_CLK"` for counterclockwise. `"CLK"` for clockwise. The default value is `"CT_CLK"`.
+
+## Examples
+
+    use <fibonacci_lattice.scad>;
+
+    n = 200;
+    radius = 20;
+    pts = fibonacci_lattice(n, radius);
+
+    for(p = pts) {
+        translate(p)
+            sphere(1);
+    }
+        
+    sphere(radius);
+
+
+![fibonacci_lattice](images/lib2x-fibonacci_lattice-1.JPG)
+
+    use <fibonacci_lattice.scad>;
+    use <hull_polyline3d.scad>;
+
+    n = 200;
+    radius = 20;
+    pts = fibonacci_lattice(n, radius);
+
+    for(p = pts) {
+        translate(p)
+            sphere(1);
+    }
+        
+    sphere(radius);
+
+    spirals = [for(j = [0:9]) 
+        [for(i = j; i < len(pts); i = i + 8) pts[i]]
+    ];
+
+    for(spiral = spirals) {
+        hull_polyline3d(spiral, 1);	
+    }
+        
+![fibonacci_lattice](images/lib2x-fibonacci_lattice-2.JPG)

src/fibonacci_lattice.scad

@@ -1,3 +1,13 @@
+/**
+* fibonacci_lattice.scad
+*
+* @copyright Justin Lin, 2020
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib2x-fibonacci_lattice.html
+*
+**/
+
 function fibonacci_lattice(n, radius = 1, dir = "CT_CLK") =
     let(
         toDegrees = 180 / PI,