anoved · March 18, 2014 15:48 · Mar 18, 2014
diff --git a/star.scad b/star.scad
@@ -0,0 +1,30 @@
+// points = number of points (minimum 3)
+// outer  = radius to outer points
+// inner  = radius to inner points
+module Star(points, outer, inner) {
+
+	// polar to cartesian: radius/angle to x/y
+	function x(r, a) = r * cos(a);
+	function y(r, a) = r * sin(a);
+
+	// angular width of each pie slice of the star
+	increment = 360/points;
+
+	union() {
+		for (p = [0 : points-1]) {
+
+			// outer is outer point p
+			// inner is inner point following p
+			// next is next outer point following p
+
+			assign(	x_outer = x(outer, increment * p),
+					y_outer = y(outer, increment * p),
+					x_inner = x(inner, (increment * p) + (increment/2)),
+					y_inner = y(inner, (increment * p) + (increment/2)),
+					x_next  = x(outer, increment * (p+1)),
+					y_next  = y(outer, increment * (p+1))) {
+				polygon(points = [[x_outer, y_outer], [x_inner, y_inner], [x_next, y_next], [0, 0]], paths  = [[0, 1, 2, 3]]);
+			}
+		}
+	}
+}