25 minutes ago, Green_Baron said:

Ok then.

Allow me to leave this nice introduction into OpenGL here. It discusses your case (model transformations depending on time) under "Getting started" - "Transformations".

Hope you solve it !

Thanks for your great source. I will study this tutorial.

Not that long ago, it helped me a lot understanding the basic concepts, it is a real quick start. Though the actual version of OpenGL is 4.6, which again handles things slightly different, though not as principally as between 2 and 3.

The Red Book (OpenGL Programming Guide, 9th Edition) is a very good learning source with a lot of examples.