StarEngine are both forks from exactly the SAME build of CryEngine.
We stopped taking new builds from Crytek towards the end of 2015. So did Amazon.
Because of this the core of the engine that we use is the same one that Amazon
use and the switch was painless (I think it took us a day or so of two engineers
on the engine team). What runs Star Citizen and Squadron 42 is our heavily
modified version of the engine which we have dubbed StarEngine, just now our
foundation is Lumberyard not CryEngine. None of our work was thrown away or
modified. We switched the like for like parts of the engine from CryEngine to
Lumberyard. All of our bespoke work from 64 bit precision, new rendering and
planet tech, Item / Entity 2.0, Local Physics Grids, Zone System, Object
Containers and so on were unaffected and remain unique to Star Citizen.
Going forward we will utilize the features of Lumberyard that make sense for
Star Citizen. We made this choice as Amazon's and our focus is aligned in
building massively online games that utilize the power of cloud computing to
deliver a richer online experience than would be possible with an old fashioned
single server architecture (which is what CryNetwork is).
Looking at Crytek's roadmap and Amazon's we determined that Amazon was investing
in the areas we were most interested in. They are a massive company that is
making serious investments into Lumberyard and AWS to support next generation
online gaming. Crytek doesn't have the resources to compete with this level of
investment and have never been focused on the network or online aspects of the
engine in the way we or Amazon are. Because of this combined with the fact we
weren't taking new builds of CryEngine we decided that Amazon would be the best
partner going forward for the future of Star Citizen.
Finally there was no ulterior motive in the timing of the announcement. The deal
wasn't fully finalized until after the release of 2.5 and we agreed with Amazon
to announce the switch and partnership upon the release of 2.6, which would be
the first release on Lumberyard and AWS. If you have been checking out our
schedule updates you would know that we originally had hoped to release 2.6 at
the beginning of December, not Friday the 23rd!
I hope this clears up some of the speculation I have seen. We are very excited
to be partnered with Amazon and feel this move is a big win for Star Citizen and
by extension everyone that has backed the project.
p.s. I wont be replying to this as it is Christmas and I am meant to be enjoying
a bit of time off with my family (and playing some games - you may see me pop
into a Star Marine or AC match or two!)