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docs/lib2x-lines_intersection2.md

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+# lines_intersection2
+
+Find the intersection of two line segments. Return `[]` if lines don't intersect.
+
+**Since:** 2.4
+
+## Parameters
+
+- `line1` : Two points of 2D line1.
+- `line2` : Two points of 2D line2.
+- `ext` : Default to `false`, which doesn't extend a line to an intersection with another line. 
+- `epsilon` : An upper bound on the relative error due to rounding in floating point arithmetic. Default to 0.0001.
+
+## Examples
+
+    use <lines_intersection2.scad>;
+
+    line1 = [[0, 0], [0, 10]];
+    line2 = [[5, 0], [-5, 5]];
+    line3 = [[5, 0], [2.5, 5]];
+
+    assert(lines_intersection2(line1, line2) == [0, 2.5]);
+    assert(lines_intersection2(line1, line3, ext = true) == [0, 10]);