/*
 * For this samples we need to change this header file (/usr/include/gtkglext-1.0/gdk/gdkglconfig.h) because will have an compilation error.
 * replace 'GDK_IS_GL_CONFIG' with: 'GDK_GL_IS_CONFIG'
 * replace 'GDK_IS_GL_CONFIG_CLASS' with: 'GDK_GL_IS_CONFIG_CLASS'
 * I don't know if this is a bug of gtkglext.
 
 * This code do not work with compiz-fusion enabled!!!!!!