OpenGL: What's the deal with deprecation?

Question

OpenGL 3.0 and 3.1 have deprecated quite a few features I find essential. In particular, the use of fixed function in shaders.

Can anyone explain what\'s really th

Answer 1

Why do they find the need to deprecate such useful feature that its obvious everybody uses and that no sane hardware company is going to remove support for?

I suppose then Apple must be insane, because MacOSX 10.7 supports only 3.2 core. No compatibility specification support, no ARB_compatibility extension, nothing. You can either create a 2.1 context or a 3.2 core context.

However, if you want reasons:

1. For the sake of completeness: what Jesse Hall said. The ARB no longer has to consider the interaction between fixed function and new features. Integer math, array textures, and various other features are defined to not be usable with the fixed function pipeline. OpenGL has really improved over the last 3 years since GL 3.0 came out; the pace of the ARB's changes is quite substantial. Would that have been possible if they had to find a way to make all of those features interact with fixed function? And if they didn't have fixed function interactions, would you not then be complaining how you can't access new features from your old code? Which leads nicely into:

2. It serves as a strong indication of what one ought to be using. Even if the compatibility context is always available, you can look at core OpenGL to see how one ought to be approaching problem solving.

3. It makes the eventual desktop GL and GL ES unification much more reasonable. ES 2.0 threw out all of the old stuff and just adopted what you might think of as core GL 2.1. The ultimate goal will be to only have one OpenGL. To do that, you have to be able to rid the desktop GL of all of the cruft.