The spec says it should have an EXT not OES suffix, as it's enabled as
an interaction with GL_EXT_multi_draw_arrays.
On some drivers GetProcAddress() returns NULL, which causes the
GLExtensions init to fail
This 'happened' to work if GetProcAddress() doesn't return NULL on missing
functions (as allowed in EGL) - as the function appears to never be called so
this would not have been noticed.
Mesa also (incorrectly?) exports the EXT version, so this would all
happen to work there, but appears to be contrary to the spec.
This invalid prefix even ended up in the upstream khronos registry, the
issue was reported here:
https://github.com/KhronosGroup/OpenGL-Registry/issues/81
Regression introduced in e99cd57 / 4935: VideoBackends: Set the maximum
range when the depth range is oversized[1]. The NV_depth_buffer_float
extension is not part of OpenGL 3.0, and requiring it causes a hard
crash when it's not supported (e.g. macOS).
[1]: https://github.com/dolphin-emu/dolphin/pull/4935
This removes some nonsense in the extension loader where under an ES context we would still pull all function pointers and just continue onward if we
fail to pull one.
Now function pointers are only pulled if the version of GL or ES actually supports that function.
Jonathan Hamilton