The tutorial in question uses GLUT and GLEW, but I have read somewhere that GLUT is obsolete. Is that true?
Is GLUT 3.7 out of date? Absolutely. You should never use it for anything.
However, FreeGLUT is perfectly fine to use. It is 100% backwards compatible with GLUT 3.7. FreeGLUT is a good utility to have when you need to slap together a quick and dirty program.
Even though the original GLUT is not in active development anymore, its still a good tool for its targeted domain, which is quick OpenGL testing and demos. It was never intended to be a framework for developing complex OpenGL programs.
The two aims of GLUT are to allow the creation of rather portable code between operating systems (GLUT is cross-platform) and to make learning OpenGL easier. Getting started with OpenGL programming while using GLUT often takes only a few lines of code and does not require knowledge of operating system–specific windowing APIs.
So no, if you use it for quick OpenGL tests, demos and learning, then it is not obsolete.
You should have a look at GLFW: http://www.glfw.org/
It's a very easy to use cross-platform API that is still in development and has good documentation!
All it does, is to create an OpenGL context and provide means to get input (+ some extra features like threading)
Yes GLUT is obsolete and not under developement since 1998 with the release of the 3.7 version.
From French Wikipedia:
La bibliothèque GLUT n'est désormais plus en développement et s'est arrêtée à la version 3.7 en mai 1998.
Sorry for the french reference but i haven't find any date on the english wikipedia. The translation is:
The GLUT library is no longer in development and stopped at version 3.7 in May 1998.
And the link to the english wikipedia: