They're using Unreal Engine 3 (not 4), which is cross-platform. But if they've written a lot of custom shaders for DirectX (HLSL), they would have to rewrite them for OpenGL (GLSL).
In general, it's getting easier and easier to write once and run anywhere. You can build amazing things in UE4 by staying entirely within the bounds of the engine, and never dropping down into platform-specific solutions.
A lot because quality assurance testing. There is little to zero automation available and supporting three platforms (more, if you want to support distros other that Ubuntu) means tripling your already time consuming and expensive testing effort.
I'd love to see more games in Mac, bit understand why that is rarely the case since I also want a quality product and would complain if I got a poorly tested port.
I happened to watch a video of this game a few days ago, and it was the first time in maybe a decade that I was genuinely impressed by the graphics of a game. It's simply gorgeous.
It's worth mentioning that this is coming from a small, new game studio from Poland and this is their first game under the name "The Astronauts". Some of them worked in game industry before as "People can fly" [1], but it's still very impressive feat that this is the first game their new studio released.
It's beautiful work, but not a revolution. Taking pictures for geometry and textures is well worn. The techniques they're using are effective, I'll give them that. But maybe I'm jaded and was expecting a more procedural approach.
Also, how does the game actually play? lol
This is why I don't play modern games: the big houses seem to be hell bent on "realism", not catching on that we've been in the uncanny valley for over a decade and are not getting out. A computer can't simulate the experience of going for a walk, and it's a colossal waste of talent and dollars trying to get closer.
Those pictures aren't realistic in the sense that they're ever going to fool anyone. The game videos (linked above by buro9) are beautiful though. But that's because of the art, not high-fidelity rocks.
I don't know. I remember what games looked a decade ago. Doom 3 was state of the art, and we marveled at what we were looking at. Crysis only came out in 2007, an astounding improvement in graphical fidelity.
Things are certainly still improving at a rapid pace, and besides the whole point of the high-fidelity rock is to prevent that feeling where something seems out of place. I, for one, find it a triumph of both engineering and art design to use more realistic assets in games.
And besides, I've had people fooled by Icenhancer screenshots. It's true that there are other problems (human motion, facial expressions) that are harder to fix, but I'm damned if this isn't incredibly impressive.
It's beautiful. Though... Windows only.
I wonder, how much effort does it take to make a game work multi-platform (+Mac, +Linux)?