Yes, that's working fine. You have a good eye, it's an important piece of the design. The SDL input logic needs to happen in the thread that created the window, but the GL context can be accessed from another thread. There isn't really concurrency, it's just a shared context passed over from the main thread after initialization to the render thread.

Harley: yes! I should have mentioned those articles. Carmack's piece in particular is very thorough. es_core puts 'I', 'S' and 'RGV' respectively each in their own threads, input is sampled right at the beginning of RGV. "Late frame schedule time warp" would be a great addition, or even the "Continuous time warp" (which Abrash refers to as "racing the beam"). Those would need to be worked out at Ogre level though (e.g. inside the 'RGV' part). I've left the renderer as is for now, having plenty to do outside of that. Kantalol: I didn't know about Theron and libcppa. Those are definitely worth considering. I like that ZeroMQ offers bindings for a lot of languages though, and that it is supported by an active community. Far as SDL2, I picked what I'm familiar with really. I've used SDL and known the core developers for years. GLFW is a compelling alternative, it would be very easy to switch out.

We haven't explicitly tested the terrain blending in FrozenSand's q3map2 fork. It's not a feature used much in Urban Terror mapping as far as I can tell, so it may be broken. You can still compile your map for Urban Terror with the latest 'general release' q3map2 (2.5.17) that is included in GtkRadiant. You won't get the FS enhancements like the lighting model, but you can see if the terrain blending works there at least. NOTE: It's best to track these things on the project tracker, I've copied this information over: https://github.com/TTimo/GtkRadiant/issues/126

Quake 1 isn't supported in 1.6 at the moment. The games currently supported are Quake III Arena, QuakeLive, Wolfenstein: Enemy Territory and Urban Terror. Support for games that were in older release lines of the editor (such as Quake 1), would be pretty easy to add back. They are not included yet because no programmer has made a commitment to support them, and we have committed to "A small subset of well supported games" for 1.6 rather than the old approach of putting in as many game packs as we could. You will find more details about this in the Mission Statement section of the website.

I remember having a look at wings3d. However someone would have to make a good case to me that Erlang is the right tool for the job on this one. While it's a finely crafted piece of engineering, I don't feel that Erlang is meant as a general purpose language. Haskell has several traits that make it more suitable for general purpose work imo.

Gaming is changing fast and I want to stay close to the technologies and media platforms that I think are most relevant. Down the road I would still like to focus on multiplayer and esports, pushing some of my own ideas in that direction.

My presence at id wasn't going to make a Linux release more likely to happen. That didn't factor into my decision to leave, but I want to avoid any misconceptions about how much influence I had at the studio.