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docs/lib-midpt_smooth.md

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+# midpt_smooth
+
+Given a 2D path, this function constructs a mid-point smoothed version by joining the mid-points of the lines of the path. 
+
+**Since:** 1.3
+
+## Parameters
+
+- `points` : The path points.
+- `n` : Perform mid-point smoothing n times.
+- `closed` : Is the points a 2D shape? If it's `true`, the function takes the last point and the first one to calculate a middle point. Default to `false`.
+
+## Examples
+
+    include <hull_polyline2d.scad>;
+    include <shape_taiwan.scad>;
+    include <bijection_offset.scad>;
+    include <midpt_smooth.scad>;
+
+    taiwan = shape_taiwan(50);  
+    smoothed = midpt_smooth(taiwan, 20, true);
+
+    translate([0, 0, 0]) hull_polyline2d(taiwan, .25); 
+    #translate([10, 0, 0]) hull_polyline2d(smoothed, .25);
+
+![midpt_smooth](images/lib-midpt_smooth-1.JPG)