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docs/lib2x-ptf_bend.md

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+# ptf_bend
+
+Transforms a point inside a rectangle to a point of an arc.
+
+**Since:** 2.3.
+
+## Parameters
+
+- `size` : 2 value array `[x, y]`, rectangle with dimensions `x` and `y`.
+- `point` : The point to be transformed.
+- `radius` : The radius of the arc.
+- `angle` : The central angle of the arc.
+
+## Examples
+
+    use <pixel/px_ascii.scad>;
+    use <ptf/ptf_bend.scad>;
+
+    t = "dotSCAD";
+    size = [len(t) * 8, 8];
+    radius = 20;
+    angle = 180;
+
+    for(i = [0:len(t) - 1]) {
+        for(pt = px_ascii(t[i], invert = true)) {
+            bended = ptf_bend(size, pt + [i * 8, 0], radius, angle);
+            translate(bended)
+                sphere(0.5, $fn = 24);
+        }
+    }
+
+![ptf_bend](images/lib2x-ptf_bend-1.JPG)