Oddly enough it seems like C++ is the only language all three platforms support natively.
Oddly enough it seems like C++ is the only language all three platforms support natively.
Indeed. But it's also quite harder than those to develop in.
I hate to keep on button-mashing, but it would be a big win to have a PlusPlusScript language - as in same philosophy and approach as CoffeeScript, but targeting C++ [1].
Does keeping C# as a constant really solve this problem? (I honestly don't know, I've never done a multiplatform product like this)
I've deployed ASP.NET MVC apps on Linux / Mono and it was a relatively painless experience. The desktop and RIA guys in .NET land are doing their own thing with WPF and Silverlight (google MVVM / Caliburn-Micro), and frankly, it's freaking me out a bit. There's a tendency to overengineer and abstract everything. It might not be as bad as with Java but the tendency is still there.
For instance, the .NET community has been arguing for years about domain driven design and how you should abstract away (or not!) database access. Hundreds of blog posts about which application layer should be concerned with this and that, about generic data access repositories, enhanced query objects and so on. What was "the way to go" one day was suddenly "the new singleton". Some guys eventually came up with the glorious "CQRS" approach (inspired by Betrand Meyer's command query separation) and built entire frameworks such as NCQRS with separate read/write stores, event sourcing and audit trails. The problem is that a lot of people start to use these enterprise models in very simple applications.
I'd also say that the 3 mentioned languages are, in their current incarnations, very different from each other. Java itself looks rather stagnant to me? I don't know, the last time I checked I saw former high school / college friend of mine starting a serious open source effort for easier database querying because he was so fed up with hibernate - it's basically one gigantic DSL / fluent interface that generates sql. Me: "Why don't you use lambda expressions.. oh wait, ...".
With a properly architected solution (and I like to think mine comes close) with sufficient abstraction, I literally can write a game once--with allowances for fundamental platform differences, i.e. "is this a touch device? then show on-screen controls, but wire them to the same backend logic"--and deploy it everywhere. I can't do that with a Java engine on Android and an Obj-C (ugh) engine on iOS, because there is no reasonable lingua franca. C#, on the other hand, works fairly well everywhere. The platform-specific bits are small, clearly delineated, and shouldn't take long to do (it's Windows-only for now).
I'd take re-coding my UI layer over having to write near-identical code for XNA and OpenGL, then writing near-identical code for OpenAL, XNA, and Core Audio, then writing widely divergent input code for XNA and whatever not-well-standardized gamepad layers I can repurpose or build for Linux and OS X and the different touch frameworks...
Having to write all of this stuff is arguably on par, if not more complex and difficult, than reimplementing a UI layer. It's not a "luxury" at all.
Is C# the right language to do that in, maybe, maybe not but it is an option.