This past month Valve confirmed that it was developing a brand new Half-Life game. Half-Life: Alyx, which launches in March, marks a return to one of Valve's most popular and successful franchises. It turns out Half-Life: Alyx wasn't the only popular Valve property that the studio was considering revisiting, however. A new Portal game has now been revealed, though the game has long been canceled. Nevertheless, it shows Valve's growing interest in revisiting not just Half-Life, but Portal as well.
Valve's now-canceled Portal game was originally named, or codenamed, Aperture Camera. Valve, either for the sake of transparency or just because Aperture Camera was such a cool idea, released the source code for the game to LunchHouse Software. LunchHouse is taking this code and is creating a video series detailing the game and its development. This series is named Exposure and already has its first video released, introducing the core gameplay mechanic that Aperture Camera was based on.
The Aperture Camera game was, apparently, built around an actual in-game camera made by the Aperture Corporation. The camera is the gameplay mechanic. In the short video released by LunchHouse, the studio shows how this camera is used in-game. Players take photos of objects, with turn the object into a photograph. This photograph can then be used to return the object to the world, though at either a larger or smaller scale than it was before.
How the concept of scaling objects can be used to create interesting puzzles is clear. For the time being, however, no video has been provided of what kind of puzzles Valve thought up. The first video simply shows how the gameplay mechanic works. Interested Valve fans can expect more information as LunchHouse releases further videos in its Exposure series.
It's also notable that while the camera itself makes sense as an Aperture invention, the game doesn't otherwise seem to fit into the Portal universe. Some information has also been shared about that. Apparently Aperture Camera was intended to be a prequel to the Portal games. As such, it wouldn't feature Glados or Chell. How Valve would fit the game into the greater Portal universe may never be revealed.
Aperture Camera not fitting in with the Portal universe may be one of the reasons the game was canceled. It may also have to do with another game, Superliminal, which used a similar gameplay mechanic sans camera. Hopefully, LunchHouse's video series also goes into detail about the reason for Valve's cancellation of Aperture Camera.