Where are the decompression mechanics we first saw at Gamescom 2015?
TL;DRRoberts says decompression is on hold because its physics programmer is busy on the physics-driven flight system refactor, though an early prototype exists and most needed systems are in place, awaiting foundational engine work.
This is another one of those priority things on the list. It's something we started to play around with, but the physics programmer who was doing it, David Coulson, is front and center in what we're refactoring, the more physics-driven IFCS. So that's on hold. But once we get it done... He first started the prototype, because we have the room system, and so we know what the air and oxygen is. The room system bleeds out, so we know the amount of bleed-out. And here we go, this is a test. When the doors open, there you are: there's a vacuum out there, and then there was oxygen, and the room system bled out to there. And it only happened when the door fully opened, because in that particular test the door was basically saying, "Once it's opened, I'm open," versus, as you opened it, it would increase, which would be something we would fix. This is just a very early prototype, but that's basically applying a force on all the objects that are inside the room based on how fast the atmosphere or the gas was exiting the room. So we have most of the systems to do that. It's just pulling them all together.
There's just so much foundational stuff. I personally have been working on a refactor of the attachment and physics stuff in the engine, which will give us a pretty big performance boost, hopefully, when it's all in. But again, it's refactoring things to think about the scalability of the engine in our use case, because whether it's what we're using, which is CryEngine slash Lumberyard, or even if we were using Unreal or Unity, they're not built to have the size of world and the amount of objects to simulate. So we're doing a lot of work that changes the thinking, because we have to think about how this thing scales with worlds of this size and object counts of this size. And so that requires a lot of rework and refactoring. So there's a fair amount of engineering that always happens where you don't see the sexy results. It's under the hood, but then it enables you to have a much bigger and more immersive world.