add perlin_noise_cylinder

examples/perlin_noise_cylinder.scad

@@ -0,0 +1,57 @@
+use <util/rand.scad>;
+use <experimental/pnoise2.scad>;
+use <experimental/sf_solidify.scad>;
+use <experimental/ptf_bend.scad>;
+
+radius = 40;
+height = 100;
+thickness_scale = 1;
+step = 4;
+
+module perlin_noise_cylinder(radius, height, thickness_scale, step) {
+    size = [PI * radius, height];
+    
+    surface_insde = [
+        for(y = [0:step:size[1]])
+            concat(
+                [
+                    for(x = [0:step:size[0] - 1])
+                    [x / 10, y / 10, 0] 
+                ],
+                [[size[0] / 10, y / 10, 0]]
+            )
+    ];
+    
+    seed = rand(0, 256);
+    surface_outside = [
+            for(ri = [0:len(surface_insde) - 1])
+                let(ns = pnoise2(surface_insde[ri], seed))
+                    [
+                        for(ci = [0:len(ns) - 1])
+                            [surface_insde[ri][ci][0], surface_insde[ri][ci][1], thickness_scale * (ns[ci] + 1)]
+                    ]
+        ];
+
+    size_div_10 = size / 10;
+    radius_div_10 = radius / 10;
+    t_surface_outside = [
+            for(row = surface_outside)
+                [for(p = row)
+                    ptf_bend(size_div_10, p, radius_div_10, 180)
+                ]
+        ];
+    t_surface_insde = [
+        for(row = surface_insde)
+            [for(p = row)
+                ptf_bend(size_div_10, p, radius_div_10, 180)
+            ]
+    ];
+ 
+    scale(10) {
+       sf_solidify(t_surface_outside, t_surface_insde);
+       mirror([0, 1, 0]) 
+           sf_solidify(t_surface_outside, t_surface_insde);
+    }
+}
+
+perlin_noise_cylinder(radius, height, thickness_scale, step);