add voronoi_fibonacci2

examples/voronoi/voronoi_fibonacci2.scad

@@ -0,0 +1,39 @@
+use <experimental/nz_cells.scad>;
+use <golden_spiral.scad>;
+use <function_grapher.scad>;
+use <ptf/ptf_rotate.scad>;
+
+size = [150, 150];
+thickness = 5;
+height_factor = 0.7;
+pixel_step = 0.75;
+spirals = 1;
+spiral_from = 5;
+spiral_to = 10;
+spiral_pt_dist = 10;
+
+
+half_size = size / 2;
+half_pixel_step = pixel_step / 2;
+pts_angles = golden_spiral(
+    from = spiral_from, 
+    to = spiral_pt_dist, 
+    point_distance = spiral_pt_dist
+);
+
+a_step = 360 / spirals;
+cells = [
+    for(i = [0:spirals - 1])
+        for(pt_angle = pts_angles) 
+            ptf_rotate(pt_angle[0], i * a_step)
+];
+noised = [
+    for(y = [-half_size[1]:pixel_step:half_size[1]]) 
+        [
+            for(x = [-half_size[0]:pixel_step:half_size[0]]) 
+            let(n = nz_cells(cells, [x, y] * height_factor) )
+                [x, y, n < half_pixel_step ? half_pixel_step : n]
+        ]
+];
+
+function_grapher(noised, thickness);