add docs

README.md

@@ -192,8 +192,8 @@ See [examples](examples).
 ### Noise (2.3 Preview)
 - [noise/nz_perlin1](https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin1.html)
 - [noise/nz_perlin1s](https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin1s.html)
-- noise/nz_perlin2
-- noise/nz_perlin2s
+- [noise/nz_perlin2](https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin2.html)
+- [noise/nz_perlin2s](https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin2s.html)
 - noise/nz_perlin3
 - noise/nz_perlin3s
 - noise/nz_worley1

docs/lib2x-nz_perlin2.md

@@ -0,0 +1,37 @@
+# nz_perlin2
+
+Returns the 2D [Perlin noise](https://en.wikipedia.org/wiki/Perlin_noise) value at the (x, y) coordinate.
+
+**Since:** 2.3
+
+## Parameters
+
+- `x` : The x coordinate.
+- `y` : The y coordinate.
+- `seed` : The random seed.
+
+## Examples
+
+    use <util/rand.scad>;
+    use <hull_polyline2d.scad>;
+    use <function_grapher.scad>;
+    use <noise/nz_perlin2.scad>;
+    use <contours.scad>;
+
+    seed = rand(0, 255);
+    points = [
+        for(y = [0:.1:10])
+        [
+            for(x = [0:.1:10])
+            [x, y, nz_perlin2(x, y, seed)]
+        ]
+    ];
+
+    function_grapher(points, 1);
+
+    translate([11, 0])
+    for(isoline = contours(points, 0)) {
+        hull_polyline2d(isoline, width = .1);
+    }  
+
+![nz_perlin2](images/lib2x-nz_perlin2-1.JPG)

docs/lib2x-nz_perlin2s.md

@@ -0,0 +1,32 @@
+# nz_perlin2s
+
+Returns 2D [Perlin noise](https://en.wikipedia.org/wiki/Perlin_noise) values at (x, y) coordinates.
+
+**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.
+
+## Examples
+
+    use <util/rand.scad>;
+    use <hull_polyline2d.scad>;
+    use <function_grapher.scad>;
+    use <noise/nz_perlin2s.scad>;
+    use <contours.scad>;
+
+    seed = rand(0, 255);
+
+    for(y = [0:.1:10]) {
+        points = [for(x = [0:.1:10]) [x, y]];
+        noises = nz_perlin2s(points, seed);
+        for(i = [0:len(points) - 1]) {
+            translate(points[i])
+            linear_extrude(noises[i] + 1)
+                square(.1);
+        }
+    }
+
+![nz_perlin2s](images/lib2x-nz_perlin2s-1.JPG)

src/experimental/demo/nz_perlin1_demo.scad

@@ -1,18 +0,0 @@
-use <hull_polyline2d.scad>;
-use <util/rand.scad>;
-use <experimental/zip.scad>;
-use <noise/nz_perlin1.scad>;
-use <noise/nz_perlin1s.scad>;
-
-seed = rand();
-hull_polyline2d(
-    [for(x = [0:.1:10]) [x, nz_perlin1(x, seed)]], width = .1
-);
-
-xs = [for(x = [0:.2:8.3]) x];
-ys = nz_perlin1s(xs);
-
-translate([0, 2])
-    hull_polyline2d(
-        zip([xs, ys]), width = .1
-    );

src/experimental/demo/nz_perlin2_demo.scad

@@ -1,48 +0,0 @@
-use <util/rand.scad>;
-use <function_grapher.scad>;
-use <noise/nz_perlin2s.scad>;
-
-module demo1() {
-    points = [
-        for(y = [0:.2:10])
-            for(x = [0:.2:10])
-                [x, y]
-    ];
-    noise = nz_perlin2s(points);
-    
-    for(i = [0:len(points) - 1]) {
-        c = (noise[i] + 1.1) / 2;
-        color([c, c, c])
-        translate(points[i])
-            square(.2);
-    }
-}
-
-
-module demo2() {
-    points = [
-        for(y = [0:.2:10])
-            [
-                for(x = [0:.2:10])
-                [x, y]
-            ]
-    ];
-
-    seed = rand(0, 256);
-    function_grapher(
-        [
-            for(ri = [0:len(points) - 1])
-                let(ns = nz_perlin2s(points[ri], seed))
-                    [
-                        for(ci = [0:len(ns) - 1])
-                            [points[ri][ci][0], points[ri][ci][1], ns[ci]]
-                    ]
-        ], 
-        0.25)
-    ;
-}
-
-demo1();
-
-translate([12, 0]) 
-    demo2();

src/noise/nz_perlin2.scad

@@ -1,3 +1,13 @@
+/**
+* nz_perlin2.scad
+*
+* @copyright Justin Lin, 2020
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin2.html
+*
+**/
+
 use <util/rand.scad>;
 use <noise/_impl/_pnoise2_impl.scad>;
 

src/noise/nz_perlin2s.scad

@@ -1,3 +1,13 @@
+/**
+* nz_perlin2s.scad
+*
+* @copyright Justin Lin, 2020
+* @license https://opensource.org/licenses/lgpl-3.0.html
+*
+* @see https://openhome.cc/eGossip/OpenSCAD/lib2x-nz_perlin2s.html
+*
+**/
+
 use <util/rand.scad>;
 use <noise/_impl/_pnoise2_impl.scad>;