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diff --git a/examples/use_RGBclass.cpp b/examples/use_RGBclass.cpp
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+/*
+ #
+ #  File        : use_RGBclass.cpp
+ #                ( C++ source file )
+ #
+ #  Description : A small code that shows how to write a CImg plugin to
+ #                handle color image manipulation using a user-defined RGB
+ #                class, instead of using classical pixel access of CImg<T>
+ #                with operator().
+ #                This file is a part of the CImg Library project.
+ #                ( http://cimg.eu )
+ #
+ #  Copyright   : David Tschumperle
+ #                ( http://tschumperle.users.greyc.fr/ )
+ #
+ #  License     : CeCILL v2.0
+ #                ( http://www.cecill.info/licences/Licence_CeCILL_V2-en.html )
+ #
+ #  This software is governed by the CeCILL  license under French law and
+ #  abiding by the rules of distribution of free software.  You can  use,
+ #  modify and/ or redistribute the software under the terms of the CeCILL
+ #  license as circulated by CEA, CNRS and INRIA at the following URL
+ #  "http://www.cecill.info".
+ #
+ #  As a counterpart to the access to the source code and rights to copy,
+ #  modify and redistribute granted by the license, users are provided only
+ #  with a limited warranty  and the software's author,  the holder of the
+ #  economic rights,  and the successive licensors  have only  limited
+ #  liability.
+ #
+ #  In this respect, the user's attention is drawn to the risks associated
+ #  with loading,  using,  modifying and/or developing or reproducing the
+ #  software by the user in light of its specific status of free software,
+ #  that may mean  that it is complicated to manipulate,  and  that  also
+ #  therefore means  that it is reserved for developers  and  experienced
+ #  professionals having in-depth computer knowledge. Users are therefore
+ #  encouraged to load and test the software's suitability as regards their
+ #  requirements in conditions enabling the security of their systems and/or
+ #  data to be ensured and,  more generally, to use and operate it in the
+ #  same conditions as regards security.
+ #
+ #  The fact that you are presently reading this means that you have had
+ #  knowledge of the CeCILL license and that you accept its terms.
+ #
+*/
+
+#ifndef cimg_plugin
+#define cimg_plugin "examples/use_RGBclass.cpp"  // Path of the plugin is relative to the CImg.h file
+#include "CImg.h"
+using namespace cimg_library;
+#ifndef cimg_imagepath
+#define cimg_imagepath "img/"
+#endif
+
+// Main procedure
+//----------------
+int main() {
+
+  // Load images.
+  CImg<short> img1(cimg_imagepath "milla.bmp");
+  const CImg<float> img2 = CImg<float>(cimg_imagepath "parrot.ppm").resize(img1,3);
+  const float default_color[] = { 30,30,80 };
+
+  // Modify 'img1' using the RGB pixel accessor.
+  cimg_forXY(img1,x,y)
+    if (!((x*y)%31)) img1.RGB_at(x,y) = default_color;
+    else if ((x+y)%2) img1.RGB_at(x,y) = img2.RGB_at(x,y);
+  img1.display();
+
+  // Quit.
+  return 0;
+}
+
+#else
+
+//-------------------------
+// Start of the plugin code
+//-------------------------
+
+// Define a simple structure of *references* to R,G,B values.
+//-----------------------------------------------------------
+// (Feel free to add your own operators in there !)
+struct st_RGB {
+  T _R,_G,_B,&R,&G,&B;
+
+  // Construct from R,G,B references of values.
+  st_RGB(const T& nR, const T& nG, const T& nB):_R(nR),_G(nG),_B(nB),R(_R),G(_G),B(_B) {}
+  st_RGB(T& nR, T& nG, T& nB):R(nR),G(nG),B(nB) {}
+
+  // Copy constructors.
+  st_RGB(const st_RGB& rgb):_R(rgb.R),_G(rgb.G),_B(rgb.B),R(_R),G(_G),B(_B) {}
+  template<typename t>
+  st_RGB(const t& rgb):_R(rgb[0]),_G(rgb[1]),_B(rgb[2]) {}
+
+  // Assignement operator.
+  st_RGB& operator=(const st_RGB& rgb) {
+    R = (T)(rgb[0]); G = (T)(rgb[1]); B = (T)(rgb[2]);
+    return *this;
+  }
+  template<typename t>
+  st_RGB& operator=(const t& rgb) {
+    R = (T)(rgb[0]); G = (T)(rgb[1]); B = (T)(rgb[2]);
+    return *this;
+  }
+
+  // Data (R,G or B) access operator.
+  const T& operator[](const unsigned int i) const {
+    return i==2?B:(i==1?G:R);
+  }
+  T& operator[](const unsigned int i) {
+    return i==2?B:(i==1?G:R);
+  }
+
+  // Print instance on the standard error.
+  const st_RGB& print() const {
+    std::fprintf(stderr,"{ %d %d %d }\n",(int)R,(int)G,(int)B);
+    return *this;
+  }
+};
+
+// Define CImg<T> member functions which return pixel values as st_RGB instances.
+//--------------------------------------------------------------------------------
+const st_RGB RGB_at(const int x, const int y=0, const int z=0) const {
+  const int whz = width()*height()*depth();
+  const T *const pR = data() + x + y*width() + z*width()*height(), *const pG = pR + whz, *const pB = pG + whz;
+  return st_RGB(*pR,*pG,*pB);
+}
+
+st_RGB RGB_at(const int x, const int y=0, const int z=0) {
+  const int whz = width()*height()*depth();
+  T *const pR = data() + x + y*width() + z*width()*height(), *const pG = pR + whz, *const pB = pG + whz;
+  return st_RGB(*pR,*pG,*pB);
+}
+
+//------------------------
+// End of the plugin code
+//------------------------
+#endif