GLSL vs Nvidia CG SDK

[IceColdDuke]

Ive been programming with the NVIDIA CG Sdk, and my friend told me that GLSL is faster, is that true? If not what are the main differences between the two?

[DudeMiester]

Nothing. They are just different front-ends, although CG may have some extra features before GLSL does. However, in the end it's all the same to the GPU.

[The Chiropractor]

The main difference between a lot of these is generally syntax in the representation as the languages are generallydesigned to wrap common functionality at the lower level.

I am not certain of this but I have heard that support for
Cg was being discontinued or something. Anyway I am
unsure of this but with regards to the method of
implementing your vertex and fragment programs just
use whatever method your used to.

You might also want to note that the Cg compiler can compile for profiles that are older than the standard 'original' programmable specification using custom extensions on nVidia cards so it may be useful in this regard over say trying to implement your own frontend to do a lower details special effect by doing the gruntwork yoursellf (ie querying extensions, filling values etc).