I have an old OpenGL 2.1 book (the red one) that I started reading years ago. Now I'm thinking about picking up where I left, but are not sure if I need a newer version of the book.
The idea is; if newer OpenGL versions only added new features, and deprecated a few odd ones, I can learn the basics with the 2.1 version and when I'm comfortable with its functions (will take a while...), buy the newest version of the book to learn the rest.
But I remember there where supposed to be some fundamental changes to the way OpenGL works, that was supposed to be included in 3.0 but never was, something with OpenGL states. Did it get included in 3.1-4.2? If so, it would be better to start with a new version of the book and forget all about the old ways. If not, I will stick with the old one and see if I get through it this time.
Grateful for your thoughts.