added shape_superformula.scad

src/__private__/__to_degree.scad

@@ -0,0 +1 @@
+function __to_degree(phi) = 180 / 3.14159 * phi;

src/shape_superformula.scad

@@ -0,0 +1,30 @@
+include <__private__/__ra_to_xy.scad>;
+include <__private__/__to_degree.scad>;
+include <__private__/__triangles_radial.scad>;
+
+function _superformula_r(angle, m1, m2, n1, n2 = 1, n3 = 1, a = 1, b = 1) = 
+    pow(
+        pow(abs(cos(m1 * angle / 4) / a), n2) + 
+        pow(abs(sin(m2 * angle / 4) / b), n3),
+        - 1 / n1    
+    );
+
+function shape_superformula(phi_step, m1, m2, n1, n2 = 1, n3 = 1, a = 1, b = 1) = 
+    let(
+        pts = [
+            for(phi = [0:phi_step: 6.28318]) 
+                let(
+                    angle = __to_degree(phi),
+                    r = _superformula_r(angle, m1, m2, n1, n2, n3, a, b)
+                    
+                )
+                __ra_to_xy(r, angle)
+        ],
+        shape_pts = concat([[0, 0]], pts, [pts[0]]),
+        triangles = __triangles_radial(shape_pts)
+        
+    )
+    [
+        shape_pts,
+        triangles
+    ];