Its a fact today that almost every AAA video game released for the PC, Xbox or PS3 is written entirely in C++. Some vendors say they can’t move to C# because large codebases for the various engines they reuse internally are already built and tested in C++ (physics, rendering, etc). And performance-wise, its a generally accepted fact that C++ code runs faster than C#.
To re-iterate : Why does the professional game-dev industry in general use C++, and why don’t we? Is it because the general line-of-business application doesn’t require the “best performance you can get” and trading reliability (memory leaks, OOBs, stack overflows) for performance “isn’t important”? Or is it just because C++ is generally “harder to maintain” (templates, pointers, malloc, etc) than the same code written in C#?
Or is it because development in C++ is “more time consuming” than developing the same featureset in C#, so you can’t implement as many features as you’d like to? But even today, many high-end game-dev kits such as UDK and CryENGINE are written entirely in C++ and their featureset is among the best you can get on any platform. So if C++ isn’t “harder” or “limiting” or “buggier” for such companies then why is it used so little outside the game-dev or scientific/HPC industries?
It’s not primarily about the language, it’s the platform.
In .Net you can’t use SSE, your ability to use the GPU is limited; some lock-free multithreaded algorithms can only really be implemented as originally intended (versioned pointers) in native code (and if multithreading is important, an efficient lock-free structure can provide great speed improvements); memory management is automatic in .Net whereas in high-performance scenarios you can gain a great speed benefit by micro-managing memory (separate mini-heaps for different object types), and you can vector through memory – which also links back to SSE where frequently you will have multiple pointers vectoring through large buffers, feeding values into SSE operations.
To name just a few.
These things are things that Business apps typically don’t concern themselves with because if performance is really crucial at this level then it’s likely to be a server it’s running on ~(desktop apps are unlikely – even in trading scenarios it’s likely to be the server that needs to be real-time), and a business who needs that performance will just chuck a faster machine at it; or a blade centre.
In a retail game environment it has to work on lots of different configurations of hardware, and so it makes sense to try and squeeze every last drop of performance out of whatever hardware the user is running.
I guess that more answers why C++ is used to code most games, rather than why .Net is ubiquitous in business – the lack of need of such performance potential is a factor, of course, as is I think the shorter development life cycle (generally speaking). However there are more factors.
In some ways, though, it’s like comparing apples to cows. You select the tech that best fits the problem.