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diff --git a/res/effectlib/random255.glsllib b/res/effectlib/random255.glsllib
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+/****************************************************************************
+**
+** Copyright (C) 2014 NVIDIA Corporation.
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt 3D Studio.
+**
+** $QT_BEGIN_LICENSE:GPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 or (at your option) any later version
+** approved by the KDE Free Qt Foundation. The licenses are as published by
+** the Free Software Foundation and appearing in the file LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// random [0..255] calculated by some simple Linear Congruential Generator (LCG)
+// Verfied, that each function is just a permutation of {0,...,255}, that is, with 0<=x<=255, each value in [0,255] is returned once
+int random255X( in int x )
+{
+  return( ( ( 8365 * ( x & 0xFF ) + 32285 ) >> 0 ) & 0xFF );
+}
+
+int random255Y( in int x )
+{
+  return( ( ( 3152 * ( x & 0xFF ) + 11819 ) >> 4 ) & 0xFF );
+}
+
+int random255Z( in int x )
+{
+  return( ( ( 119 * ( x & 0xFF ) + 18747 ) >> 0 ) & 0xFF );
+}
+
+int random255W( in int x )
+{
+  return( ( ( 26814 * ( x & 0xFF ) + 9642 ) >> 1 ) & 0xFF );
+}
+
+ivec3 random255XYZ( in ivec3 xyz )
+{
+  return( ivec3( random255X( xyz.x ), random255Y( xyz.y ), random255Z( xyz.z ) ) );
+}