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diff --git a/src/silx/gui/plot/utils/intersections.py b/src/silx/gui/plot/utils/intersections.py
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+++ b/src/silx/gui/plot/utils/intersections.py
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+# /*##########################################################################
+#
+# Copyright (c) 2017-2018 European Synchrotron Radiation Facility
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# ###########################################################################*/
+"""This module contains utils class for axes management.
+"""
+
+__authors__ = [
+    "H. Payno",
+]
+__license__ = "MIT"
+__date__ = "18/05/2020"
+
+
+import numpy
+
+
+def lines_intersection(line1_pt1, line1_pt2, line2_pt1, line2_pt2):
+    """
+    line segment intersection using vectors (Computer Graphics by F.S. Hill)
+
+    :param tuple line1_pt1:
+    :param tuple line1_pt2:
+    :param tuple line2_pt1:
+    :param tuple line2_pt2:
+    :return: Union[None,numpy.array]
+    """
+    dir_line1 = line1_pt2[0] - line1_pt1[0], line1_pt2[1] - line1_pt1[1]
+    dir_line2 = line2_pt2[0] - line2_pt1[0], line2_pt2[1] - line2_pt1[1]
+    dp = line1_pt1 - line2_pt1
+
+    def perp(a):
+        b = numpy.empty_like(a)
+        b[0] = -a[1]
+        b[1] = a[0]
+        return b
+
+    dap = perp(dir_line1)
+    denom = numpy.dot(dap, dir_line2)
+    num = numpy.dot(dap, dp)
+    if denom == 0:
+        return None
+    return (
+        (num / denom.astype(float)) * dir_line2[0] + line2_pt1[0],
+        (num / denom.astype(float)) * dir_line2[1] + line2_pt1[1],
+    )
+
+
+def segments_intersection(seg1_start_pt, seg1_end_pt, seg2_start_pt, seg2_end_pt):
+    """
+    Compute intersection between two segments
+
+    :param seg1_start_pt:
+    :param seg1_end_pt:
+    :param seg2_start_pt:
+    :param seg2_end_pt:
+    :return: numpy.array if an intersection exists, else None
+    :rtype: Union[None,numpy.array]
+    """
+    intersection = lines_intersection(
+        line1_pt1=seg1_start_pt,
+        line1_pt2=seg1_end_pt,
+        line2_pt1=seg2_start_pt,
+        line2_pt2=seg2_end_pt,
+    )
+    if intersection is not None:
+        max_x_seg1 = max(seg1_start_pt[0], seg1_end_pt[0])
+        max_x_seg2 = max(seg2_start_pt[0], seg2_end_pt[0])
+        max_y_seg1 = max(seg1_start_pt[1], seg1_end_pt[1])
+        max_y_seg2 = max(seg2_start_pt[1], seg2_end_pt[1])
+
+        min_x_seg1 = min(seg1_start_pt[0], seg1_end_pt[0])
+        min_x_seg2 = min(seg2_start_pt[0], seg2_end_pt[0])
+        min_y_seg1 = min(seg1_start_pt[1], seg1_end_pt[1])
+        min_y_seg2 = min(seg2_start_pt[1], seg2_end_pt[1])
+
+        min_tmp_x = max(min_x_seg1, min_x_seg2)
+        max_tmp_x = min(max_x_seg1, max_x_seg2)
+        min_tmp_y = max(min_y_seg1, min_y_seg2)
+        max_tmp_y = min(max_y_seg1, max_y_seg2)
+        if (
+            min_tmp_x <= intersection[0] <= max_tmp_x
+            and min_tmp_y <= intersection[1] <= max_tmp_y
+        ):
+            return intersection
+        else:
+            return None