From: Svilen <kru...@go...> - 2009-12-03 20:50:02
|
Hi, I was also a bit confused by the glewinfo report that the driver supports both glGenBuffers and glGenBuffersARB. It seems logical those two entry points to end-up with the same function. Besides (again from the glewinfo report) it seems strange that all openGL 1.5 functions are supported yet the driver is declared to support openGL 1.4 only. In an attempt to come up with the fix I've knocked on a couple of doors including GLEW. Here is the link http://sourceforge.net/mailarchive/forum.php?thread_name=4B1736EF.2080504%40nvidia.com&forum_name=glew-users The trouble is that I can't figure-out a clear diagnostic strategy that will work on this particular platform (with 945GM) also, because GLEW reports that the function exists i.e. it looks safe to be called. It was another suggestion in the GLEW thread - that the graphic context might be invalid. The application does have checks for this, but I'll try to reconfirm with the user that this is not the case. On 12/03/2009 07:26 PM, Ian Romanick wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Chris Wilson wrote: > >> On Wed, 02 Dec 2009 00:17:06 +0000, Svilen<kru...@go...> wrote: >> >>> Hi guys, >>> >>> A bug reported initially here (Fedora 12) >>> https://bugzilla.redhat.com/show_bug.cgi?id=541879 >>> >>> You can see from the bug reports that it involves "Mesa DRI Intel(R) 945GM GEM 20090712 2009Q2 RC3" driver. >>> >>> The application uses glew library. After calling the glewInit(), the first call to the openGL function which is glGenBuffers is causing the application to crash. >>> >>> It's a cross platform application which works on other graphic platforms/drivers on Linux as well as on Windows. Is there something I'm missing in the initialization sequence? Or there is a problem with the driver? >>> Shall I raise a bug? >>> >> This is an application bug. It is using OpenGL 2.0 features on a driver >> restricted by the capabilities of its hardware to OpenGL 1.4, so >> understandably tries to dereference a NULL function pointer when calling >> glGenBuffers. However if the application truly wishes to be cross-device, >> it can check for ARB_vertex_buffer_object and use the glGenBuffersARB >> [and friends] extension points instead. >> > I don't think that will help in this case. glGenBuffersARB and > glGenBuffers are the same function, so they share the same entry in the > dispatch table. I haven't had a chance to look at this bug yet, but > it's in my (long, continuously growing) queue. If someone else gets to > it first, I won't be terribly sad. :) > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.10 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iEYEARECAAYFAksYEM0ACgkQX1gOwKyEAw+T5wCdEdBYkzeiUiedz8vI53Ac/615 > nIkAn2drE2IZyAEkTy2vcxt7VBtq3vBH > =29k4 > -----END PGP SIGNATURE----- > |