Created attachment 118837 [details]
As the GLEW maintainer, I've been looking to support OSMesa natively in GLEW, when built in -DGLEW_OSMESA=1 mode. I had some success with on Linux, but linking with libOSMesa, rather than libGL. However, the Windows scons build does not export the OpenGL functions that GLEW needs, such as glGetString.
$ nm -D /usr/lib/x86_64-linux-gnu/libOSMesa.so | grep glGetString
000000000026e620 T glGetString
0000000000270d40 T glGetStringi
I found that GLEW utilities glewinfo and visualinfo work on Windows with OSMesa, given a patched osmesa.def, as attached.
See also: https://github.com/nigels-com/glew/pull/25