From 3be3a271e6b317a1aa9f3e0201c324f8f2f17297 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Fri, 14 Jun 2019 13:44:47 +0800
Subject: [PATCH] c-style for loop

---
 src/torus_knot.scad | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/src/torus_knot.scad b/src/torus_knot.scad
index 9d91ec1a..607f22c0 100644
--- a/src/torus_knot.scad
+++ b/src/torus_knot.scad
@@ -8,14 +8,16 @@
 *
 **/
 
-function torus_knot(p, q, phi_step) = [
-    for(phi = [0:phi_step:PI * 2])
-    let(
-        degree = phi * 180 / PI,
-        r = cos(q * degree) + 2,
-        x = r * cos(p * degree),
-        y = r * sin(p * degree),
-        z = -sin(q * degree)
-    )
-    [x, y, z]
-];
\ No newline at end of file
+function torus_knot(p, q, phi_step) = 
+    let(tau = PI * 2)
+    [
+        for(phi = 0; phi < tau; phi = phi + phi_step)
+        let(
+            degree = phi * 180 / PI,
+            r = cos(q * degree) + 2,
+            x = r * cos(p * degree),
+            y = r * sin(p * degree),
+            z = -sin(q * degree)
+        )
+        [x, y, z]
+    ];
\ No newline at end of file