   glutDisplayFunc and member function...
  Hi there,I'd like to use the glut functions from the tutorials (e.g. glutDisplayFunc, glutReshapeFunc, a.s.o.) in combination with member functions.For example I've created a viewer class, whose objects should contain the method that I want to be called by glutDisplayFunc:void viewer::start(int argc, char** argv){   (...)   glutDisplayFunc(DrawGLScene);    (...)    }GLvoid viewer::DrawGLScene(GLvoid)  {  (...) }DrawGLScene here ist a public member function in the viewer class.The compiler tells me, that the argument of type 'GLvoid (viewer::)()' doesn't match 'void (*)()'I'm really a blockhead, so has anyone an idea how to solve this issue? Thanks a lot.darkurizenEDIT: I forgot to mention that I'm coding in C++ on a Mac ;)   
  You can't pass a pointer to a member function where a pointer to a free function is expected. The only function pointers which can be passed to glutDisplayFunc are those for free functions and static member functions.   ;  Thank you, I marked the functions static and now it works.Sort of obvious, but I was somehow blind ;)Thanks.   