add loft

src/experimental/loft.scad

@@ -0,0 +1,43 @@
+use <experimental/sweep.scad>;
+   
+module loft(sections) {
+    function gcd(m, n) = n == 0 ? m : gcd(n, m % n);
+
+    function lcm(m, n) = m * n / gcd(m, n);
+
+    function inter_pts(p1, p2, n) =
+        let(
+            v = p2 - p1,
+            dx = v[0] / n,
+            dy = v[1] / n,
+            dz = v[2] / n
+        )
+        [for(i = [1:n - 1]) p1 + [dx, dy, dz] * i];
+
+    function _interpolate(sect, leng, n, i = 0) = 
+        i == leng ? [] :
+        let(
+            p1 = sect[i],
+            p2 = sect[(i + 1) % leng]
+        )
+        concat(
+            [p1], 
+            inter_pts(p1, p2, n),
+            _interpolate(sect, leng, n, i + 1)
+        );
+
+    function interpolate(sect, n) = 
+        n <= 1 ? sect : _interpolate(sect, len(sect), n);
+        
+    module _loft(sect1, sect2) {
+        lcm_n = lcm(len(sect1), len(sect2));
+        new_sect1 = interpolate(sect1, lcm_n / len(sect1));
+        new_sect2 = interpolate(sect2, lcm_n / len(sect2));
+        
+        sweep([new_sect1, new_sect2]);
+    }
+        
+    for(i = [0:len(sections) - 2]) {
+        _loft(sections[i], sections[i + 1]);
+    }
+}