i’m getting several unresolved externals with the new gl headers i downloaded from the sgi website. i’m presuming these are not supported in my libraries which are probably quite outdated. the thing is though whenever i go looking for opengl libraries i always come up with my hands empty or something several years old. why are libraries not available on the sgi website? i admit i’m quite ignorant in these matters. but something so ubiquitous as opengl you think would have resources sprinkled abundantly about the web, but there are little if only clandestine sources to virtually none. even on this the “opengl.org” website? call me crazy but something seems to be terribly outside of my understanding here. i realize i think that officially opengl is just specifications, and the implimentation is supposed to be up to the implimentors. but i’m unable to find any implimentations really available. if nothing i’m saying makes sense then it only demostrates my lack of grasp of these matters.
anyhow i’m trying to get software support for my new graphics card’s double sided stencil buffer. any help would be apreciated.
michael
opengl.obj : error LNK2001: unresolved external symbol _wglQueryPbufferARB
opengl.obj : error LNK2001: unresolved external symbol _wglGetPbufferDCARB
opengl.obj : error LNK2001: unresolved external symbol _wglCreatePbufferARB
opengl.obj : error LNK2001: unresolved external symbol _wglChoosePixelFormatARB
opengl.obj : error LNK2001: unresolved external symbol _wglDestroyPbufferARB
opengl.obj : error LNK2001: unresolved external symbol _wglReleasePbufferDCARB
opengl.obj : error LNK2001: unresolved external symbol _wglReleaseTexImageARB
opengl.obj : error LNK2001: unresolved external symbol _wglBindTexImageARB
opengl.obj : error LNK2001: unresolved external symbol _glh_get_unsupported_extensions
opengl.obj : error LNK2001: unresolved external symbol _glh_init_extensions
xxxxxxxxxxxx.obj : error LNK2001: unresolved external symbol _glActiveStencilFaceEXT
if youre using windows you can find alot of information on why that wont work.
The windows ICD systems only forwards opengl1.1 calls directly, all other calls ( extensions and core 1.2 to 1.4 calls) must be loaded by the wglGetProcAddress just as any extension… and all functions that are in the core doenst have the ending ‘ARB’ anymore ( is any wgl in the core? )
Originally posted by Mazy:
[b]if youre using windows you can find alot of information on why that wont work.
The windows ICD systems only forwards opengl1.1 calls directly, all other calls ( extensions and core 1.2 to 1.4 calls) must be loaded by the wglGetProcAddress just as any extension… and all functions that are in the core doenst have the ending ‘ARB’ anymore ( is any wgl in the core? )[/b]
then wglGetProcAddress is used by the linker and not at run-time?
if anyone cares to be helpful, what would you suggest is the best means to handle extensions. admittedly i’ve only hacked a couple myself, but i imagine its time i decide on a robust method of handling them. any suggestions?
also how often do opengl libraries change and what is the best way to stay up to date?
The latest “OpenGL files” are quite simply the latest drivers for your video card. The OpenGL ICD (e.g. nvoglnt.dll for NVidia) is included, and that’s all you need.
The only file you might want to update every now and then as a developer is glext.h. There are no updated (GL 1.2 or newer) .lib, .h or opengl32.dll files around.
If by “OpenGL libraries” you mean the core OpenGL API, it doesn’t change that often. Once a year is a rather optimistic statement. If you mean “how often do new extensions come out?”, then “all the time” is the correct answer. If it’s “how often are extensions promoted to ARB status?”, it’s not that often, perhaps once or twice a year. The best to stay up to date with OpenGL extensions is not to hope for vendors to update the headers and libraries but to use GLEW
