Some basic questions

When assuming one has GL 2.0, what texture function should she use ? EXT_texture_object or the default core ones ?

About new types for some extensions:

What to use:

GLhandleARB or GLhandle,
GLsizeiptrARB or GLsizeiptr,
GLcharARB or GLchar,
GLintptrARB or GLintptr ?

According to the glext header, suffixed ARB types is for when VBO are not existing or shader objects. So if I understand correctly I’d better use the non fixed ones, shouldn’t I ?

Also, from the get_proc_address extension, for consistencies, one should take the address of glXGetProcAddress… with using glXGetProcAddressARB ?

EXT_texture_object thats very old opengl1.1 i believe its been part of the core for donkeys years

i always choose without extension if possible eg glMulittextureCoord instead of glMulittextureCoordARB

also WRT GLhandle etc this is what was used when shader objects were an extension, since it became part of the core with gl2.0 the use of handles is droped, u use int IDs like texture/display lists etc

check the gl2.0 spec and use that in perference to the extension docoments (if the extension has been incorperated into the core gl)

Normally you should always use the core functions.

The only reason to use the old extension functions is if you need to support hardware that doesn’t support OpenGL 2.0, but supports some of the extensions seperately.

EXT_texture_object is still listed in the extension registry whereas ARB_multitexture isn’t anymore.
Why this ?

As far as I see the GL_ARB_multitexture is extension no. 1 in the ARB extensions list

But this is not the case for texture objects: there’s always the specifications.