diff --git a/src/__private__/__in_line.scad b/src/__private__/__in_line.scad
new file mode 100644
index 00000000..45f0a57e
--- /dev/null
+++ b/src/__private__/__in_line.scad
@@ -0,0 +1,8 @@
+function __in_line(line_pts, pt, epsilon = 0.0001) =
+    let(
+        pts = len(line_pts[0]) == 2 ? [for(pt = line_pts) __to3d(pt)] : line_pts,
+        pt3d = len(pt) == 2 ? __to3d(pt) : pt,
+        v1 = pts[0] - pt3d, 
+        v2 = pts[1] - pt3d        
+    )
+    (norm(cross(v1, v2)) < epsilon) && ((v1 * v2) <= epsilon);
\ No newline at end of file
diff --git a/src/__private__/__in_line2d.scad b/src/__private__/__in_line2d.scad
deleted file mode 100644
index 12430ba8..00000000
--- a/src/__private__/__in_line2d.scad
+++ /dev/null
@@ -1,6 +0,0 @@
-function __in_line2d(line_pts, pt, epsilon = 0.0001) =
-    let(
-        v1 = line_pts[0] - pt, 
-        v2 = line_pts[1] - pt
-    )
-    (norm(cross(v1, v2)) < epsilon) && ((v1 * v2) <= epsilon);
\ No newline at end of file
diff --git a/src/in_polyline.scad b/src/in_polyline.scad
index bde6ee46..d2e438ed 100644
--- a/src/in_polyline.scad
+++ b/src/in_polyline.scad
@@ -1,16 +1,12 @@
 include <__private__/__to3d.scad>;
-include <__private__/__in_line2d.scad>;
+include <__private__/__in_line.scad>;
 
 function _in_polyline_sub(pts, pt, epsilon, iend, i = 0) = 
     i == iend ? false : (
-        __in_line2d([pts[i], pts[i + 1]], pt, epsilon) ? true :
+        __in_line([pts[i], pts[i + 1]], pt, epsilon) ? true :
             _in_polyline_sub(pts, pt, epsilon, iend, i + 1)
     );
 
 function in_polyline(line_pts, pt, epsilon = 0.0001) = 
-    let(
-        pts = len(line_pts[0]) == 2 ? [for(pt = line_pts) __to3d(pt)] : line_pts,
-        pt3d = len(pt) == 2 ? __to3d(pt) : pt
-    )
-    _in_polyline_sub(pts, pt3d, epsilon, len(pts) - 1);
+    _in_polyline_sub(line_pts, pt, epsilon, len(pts) - 1);
     
\ No newline at end of file