You already know that this is a new, largely unsupported resolution to date so I won't repeat... My opinion is that it's really meant for people in offices who want to run several spreadsheets and other kinds of business/document pages side by side without having to go the multimonitor route. What happens if you set your desktop to 2560x1080 and then run the game...? You could try that --but still, I think you are going to have serious aspect ratio problems...as obviously the game (any game, really) is not done @ 21:9 resolution, but @ 16:9, or 16:10 (1920x1200 is my resolution for the game.) I think you are going to have to settle for an aspect-ratio *correct* 1920x1080 resolution, which will mean you'll have sizable black borders to either side of the game screen. But I don't think that can be helped.
This is probably the least helpful reply I can imagine. It's great that you don't have any issues - I'm very happy to hear that. Telling people that *do* have issues 'it's your fault for using an ultra-wide monitor' is not at all helpful, and doesn't contribute anything worthwhile. For what it's worth, 2560x1080 resolutions were mentioned as being supported in several places before I bought the game.
That's only because you didn't understand my post...it isn't a matter of "supporting 2560x1080"...it's a matter of supporting *the aspect ratio* of 21:9, which I do not think the game supports at all. If you play @ 1920x1080 *at the correct aspect ratio* (so that your characters appear normal, not stretched) the image will *not* fill your screen. Again, 21:9 is a non-standard aspect ratio; it's not 16:9 or 16:10 or 4:3. That's the only comment I wanted to make. The vast majority of games support one or more of those aspect ratios--few, if any that I am aware of, support an aspect-correct 21:9. You should be able to view an aspect-correct image on your monitor with this game, just don't expect it to fill the screen, that's all.
Sorry this was not what you wanted to hear...:/ Maybe you read correctly and the game does suppport an aspect-correct 21:9, but if so, then you should be able to display it, correct? Or, perhaps your GPU drivers do not yet support an aspect-correct 21:9. Main thing to deal with is the aspect ratio.
Look.... I don't want to get into a debate here. The fact is that the game *does* support different aspect ratios, including 21:9. The fact that you can dynamically scale the size of the window the game plays in while it is in windowed mode essentially proves this. I appreciate that 21:9 is a (somewhat) unusual aspect ratio. For this game (and many others), that is neither here nor there, especially given that the UI elements are 'disconnected' from eachother, and aren't being used to frame anything. When those elements are disconnected, they're drawn relative to a point on the screen.
And as tainerballs said, 21:9 is natively supported in Windows, with the option for a 21:9 resolution showing up in the resolution selection menu. It's not there under linux (probably due to some mis-communication between the x-server and the game).
So.... I understood your post. And you are incorrect in assuming the game doesn't support 21:9. It does. There's a bit of a bug in the graphics menu under linux systems that it's not showing it as an option.