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docs/lib3x-tri_subdivide.md

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+# tri_subdivide
+
+Subdivide a triangle `n` times.
+
+**Since:** 3.3
+
+## Parameters
+
+- `shape_pts` : the vertices of a 2D or 3D triangle.
+- `n` : subdivide a triangle `n` times. Default to 1.
+
+## Examples
+
+    use <shape_circle.scad>
+    use <triangle/tri_subdivide.scad>
+   
+    radius = 10;
+    tri = shape_circle(radius, $fn = 3);
+    
+    polygon(tri);
+    
+    for(n = [1:3]) {
+        subdivided = tri_subdivide(tri, n);
+        translate([radius * 2 * n, 0])
+        for(t = subdivided) {
+            offset(-.1)
+                polygon(t);
+        }
+    }
+
+![tri_subdivide](images/lib3x-tri_subdivide-1.JPG)