Imho, je .62 prostě postavená na ToH a .63 na Enfusion. V jednom rozhovoru Evžen říkal, že na .62 si otestovali co hráče zajímá na protytypech, který se blbě v ToH blbě implementovali do finální podoby a Enfusion stavěli tak, aby to šlo doladit.
At the very beginning of DayZ Standalone development, Bohemia Interactive had several different versions of our in-house Real Virtuality engine. To be specific, there was an early Arma 3 RV engine branch, Take on Helicopters RV engine branch, and the old Arma 2 RV engine branch. Besides that, the company also operated with another in-house engine – the Enforce engine used for Take on Mars.
The original DayZ standalone forked from the engine that had been previously used for Take on Helicopters, as Arma 3 was still in the middle of doing larger tech changes to its RV branch. We aimed to have a working prototype of DayZ on the Take on Helicopters engine branch, and that version of DayZ went live to Early Access.
We quickly reached the limits of that technology, and in order to empower DayZ’s vision, along with servicing all of Bohemia’s future games, we sat down and tried to wrap our heads around what we’ll need from our engine 5 – 10 years down the road. That’s where we’ve formed a separate engine team within Bohemia, and started the development on Enfusion.
Over the 4 years of Early Access development of DayZ, and development of the Enfusion Engine, we went from a monolithic beast to a modular engine with almost all engine levels created from scratch, making sure that the good things remained (rendering large, realistic open worlds) and that the problems went away (subpar performance, non-standard scripting language, complicated network communication). Now, we have a powerful new scripting language, fast and efficient renderer, better network communication, effective development tools, fantastic animation system, and much more.
The challenges of an engine for this genre are also the reason why there really isn’t a proper DayZ out there from us, or anybody else. Handling a multiplayer game with 100 players, thousands of AI actors in real time with navigation… that’s a massive challenge for any development studio, and we’ve learned a lot from this experience.