I'm interested in how huge games like The Witcher 3 and Skyrim create and save the open worlds. In my own game I used a system where I stored the map data in a file seperated by commas. For example 'stone' would code for a stone tile, and I just typed in codes for how I wanted my map to appear in the game.
I feel like this was a really innefficient and incorrect way of doing things. But, I couldn't think of a different way to get past the problem.
The creators of skyrim obviously used a level editor, but how did they actually save a map as big as skyrim's world? How is the data stored? Because with something as intricate as an amazing, 3D world, you can't store it like I did by just having codewords for different tiles that are all the same height and width.
How is it done in 2D games as well? For example Ori and the Blind Forest, which does not use a tile-based system. Or, in fact, do they not have files that hold data for the level layouts at all?