Time Travel Is ******* Hard

Awesome Article! Something This relates to is data compression. The way I've always imagined time travel was as if the world was x,y,z,t. This is easily done when all calculations are mathematically handleable as its an f(t) equation, however creating those equations is far less easy. When a random seed exists it can still be done though it would be computationally expensive since each time a random is retrieved is an important difference from other worlds. The saving the player data as you put it seems extremely difficult as you would have to save every single choice and the tick it happened. This is similar to what you mentioned only saving variables as they changed but you probably saved each npc's data as well (which would make regeneration much faster). This relates to data compression because it is unknown what the next byte will be, only that there are a series of them. Additionally, writing a streaming compressor that easily streams back out again isn't as easy as I want to believe it is.