add stereographic_foliage_scroll

examples/stereographic_projection/stereographic_foliage_scroll.scad

@@ -0,0 +1,47 @@
+use <experimental/foliage_scroll.scad>
+use <polyline_join.scad>
+use <stereographic_extrude.scad>
+
+$fn = 48;
+
+model = "BOTH"; // [BOTH, SPHERE, SHADOW]
+width = 400;
+height = 400;
+shadow_thickness = 2;
+max_spirals = 25; 
+angle_step = 360 / $fn; 
+min_radius = 15; 
+init_radius = rands(min_radius * 2, min_radius * 3, 1)[0];
+
+stereographic_foliage_scroll();
+
+module stereographic_foliage_scroll() {
+    module draw(spirals) {    
+        for(i = [0:1]) {
+            r = spirals[i][0];
+            path = spirals[i][1];
+            polyline_join(path)
+                circle(r / 6);
+        }
+
+        for(i = [2:len(spirals) - 1]) {
+            r = spirals[i][0];
+            path = spirals[i][1];
+            polyline_join([for(i = [1:len(path) - 1]) path[i]])
+                circle(r / 6);
+        }
+    }
+
+    spirals = foliage_scroll([width, height], max_spirals, init_radius, min_radius);
+
+    if(model != "SHADOW") {
+        stereographic_extrude(shadow_side_leng = width, convexity = 10, $fn = $fn * 2)
+            draw(spirals);
+    }
+
+    if(model != "SPHERE") {
+        color("black")
+        linear_extrude(shadow_thickness)
+            draw(spirals);
+    }
+}