system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: when they release a ps4 game on switch or xbox, how do they do it? What do they change program wise?
gpt
It depends on the engine.

If the game is made in a game engine that already supports multiple platforms, then it might be as simple as registering a few new variables and formats.

For other games, it might require new chunks of code to support the different hardware. And if you're unlucky: rewriting large amounts of the game.

No matter how you do it, some of the games code will have to be rewritten to support the consoles format, it's just a question of "how much"