It's been a long time since Portal's film adaptation got announced. Confirmed by Valve President Gabe Newell and J. J. Abrams during 2013's DICE summit, we've not had an update for five years, but Abrams just confirmed the Portal movie remains in active development through Warner Bros.
Speaking to IGN during a press day for Super 8’s 4K Blu-ray release, Abrams confirmed:
We actually do have a script that’s being written for the Portal movie now at Warner Bros. We’re really excited about the take and the pitch, so it feels like that thing’s finally on the rails.
JJ Abrams Confirms Portal Movie Is Still In Development
However, considering video game adaptations often remain in development hell - Metal Gear Solid being a notable example - it doesn't seem like this is being prioritised. When asked about who's writing this script, Abrams didn't comment, though he detailed his excitement for this project, further stating:
It’s got enormous potential for a lot of reasons, one of which is because of the limited narrative of the game, as ingeniously told as it is, the potential of it is so huge. It’s gonna be super fun.
As for Half-Life, those of you still waiting on a film adaptation may find yourselves disappointed. When asked about this too, Abrams simply stated "the Half-Life thing, we’re not actively involved with at the moment", referring to his production company Bad Robot. While it could be in the works elsewhere, we're not holding out hope on seeing this project anytime soon.