Re: firefox webgl

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

Patrick Welche <prlw1%cam.ac.uk@localhost> wrote:
>Interesting: the computer that prompted the note was running
>Intel HD Graphics 630, and the one I'm checking now (also
>FEATURE_FAILURE_GLXTEST_FAILED) is according to Xorg.0.log
>NOUVEAU(0): Chipset: "NVIDIA NVE4"
>GLX: Initialized DRI2 GL provider for screen 0
>
>so it all looks promising, but I don't know what firefox is trying
>to test...

It is testing for working OpenGL then for what features it supports.

The way that it does this though is to fork(2) and run a function
that makes some OpenGL calls in the child process then pipes back
the results to the parent.

My best guess is that something is wrong with thread local storage
in the child process. The child sees non-NULL values for the OpenGL
context and tries to use it instead of creating a new context.

I think the idea is that if the child doing the tests crashes then
it won't bring down the parent. Guessing that the parent is also
killed due to being in the same process group.