add superellipsoid

src/experimental/superellipsoid.scad

@@ -0,0 +1,44 @@
+use <__comm__/__frags.scad>;
+use <sweep.scad>;
+
+// e = .25;
+// n = 1;
+
+// $fn = 24;
+
+// superellipsoid(e, n);
+
+module superellipsoid(e, n) {
+	function _sgn(x) = 
+		x < 0 ? -1 :
+		x == 0 ? 0 : 
+				 1; // x > 0
+
+	function _c(w, m) = 
+		let(cosw = cos(w))
+			_sgn(cosw) * pow(abs(cosw), m);
+		
+	function _s(w, m) = 
+		let(sinw = sin(w))
+			_sgn(sinw) * pow(abs(sinw), m);
+			
+	a = 1;
+	b = 1;
+	c = 1;
+
+	u_step = 360 / __frags(1);
+	v_step = u_step / 2;
+
+	sweep([
+		for(v = [-90:v_step:90])
+			[
+				for(u = 180 - u_step; u >= -180; u = u - u_step)
+				let(
+					x = a * _c(v, n) * _c(u, e),
+					y = b * _c(v, n) * _s(u, e),
+					z = c * _s(v, n)
+				)
+				[x, y, z]
+			]
+	]);
+}