The Longest Journey HD is a mod for one of the best adventure games ever made. It includes neural network upscaled backgrounds and sprites, redrawn user interface and a lot of other small improvements thanks to ResidualVM implementation of the game engine. You can play it on Windows, Linux and macOS.
TLJHD.zip to the game installation directory. If asked, overwrite all existing files. Make sure that the path to the mod looks like this:
The Longest Journey\mods\TLJHD\. You can also download a pack of upscaled in-game videos — extract them to the game directory as well.
Add game... and choose the game (not the mod!) directory.
Load modded assets option is enabled.
Graphics tab, click
Override global graphic settings, then enable
Aspect ratio correction and
Fullscreen mode options. Enable anti-aliasing for 3D models. From my experience
4x is more than enough.
Start to launch the game.