That's a great news! Seems that Linux is getting a lot of gaming love in the last period.
We should thanks the guys behind Wasteland 2 for helping or providing the port[1].
In the 2D world, Moai now runs in Linux too. I started working for Zipline recently (working on the docs ATM), and (shameless plug) the more I become familiar with the engine, the more I appreciate its simple yet powerful programming model and its architecture.
Each graphical element (a "prop" in Moai parlance), when moved, rotated or scaled, defines its own coordinate system, and other props can be added as children and share some or all of the new coordinates. It makes it very easy to compose elements. People familiar with 3D graphics would know this as affine transforms and UV coordinates.
For example, you can tie the position and scale of a text label to a sprite, but not its rotation, and tie the scale, rotation and position of the sprite to the background. You can then zoom everyting in one command, rotate the wole game world or and keep the label next to the sprite and rotate the whole scene or the sprite relative to the map while leaving the label straight. You don't have to track the relative angles, the engine does it for you.
Similarly, every object whose properties depends on time ("actions") can be attached or detached not only to the root action (which provide a tick each frame) but to other actions as well. When you detach an item, its descendants are also paused. Actions include animations, coroutines, physiscs worlds, you name it...
Both trees are defined declaratively in Lua, and implemented in C++, giving the best of both worlds: expressivity and speed.
Moai's biggest flaw at the moment is the sparse documentation, and we're tackling it. Right now, the main focus of the dev team is the cloud offering (which is our revenue source, after all), so it does not proceed as fast as we would like, but come back in a few weeks and you should see a vastly improved documentation.
I did have a look at Moai (I work with Unity normally) but indeed, the documentation just wasn't there so I gave up and went back to Unity. I'll keep an eye on it.
Hey .. just wondering how the documentation is going? I'm an avid MOAI user and would love to know more about whats planned in the immediate future for the doc catchup ..
[1] http://www.kickstarter.com/projects/inxile/wasteland-2/posts...