I am just wondering how some things work in gamedev:
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I know, that the performance is actually crucial so there is still (and I think never will be) no place to use managed languages/platforms as Java/.NET just because of their performance. But… recently I have read somewhere here on SO, that even though people creating games use C++ as a primary language, they actually do not use STL or Boost (or a lot of them). In think it has something in common with performance, right? If I am wrong, could you please tell me what are the reasons to avoid those libraries (that I think make developer’s life much easier)? Is it because of licensing (Boost)? And what about EA’s version of STL? Do other studios make their own versions too?
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How “close to metal” game programming really is? Do you go deeper and closer to the machine? Do you sometimes use Assembly for critical inner loops, or C++ is actually the lowest abstraction layer that you use at the moment? I assume that in such products where performance is the most important thing profiling is very, very common task – but are you sometimes forced to use assembly to speed some parts up, or good C++ is “good enough”?
Edit:
Sorry, It may not have been clear, but I am interested in answers from people having game industry experience. I am not interested in some assumptions given by people who do not have commercial experience in game development. I am also not interested in examples of some niche-games created in C#/Java whatever. However if you know a product that looks better than FarCry2 (just and example, but your favourite modern great looking game name here), and is written entirely in Java/.NET, and has similar performance to FarCry2… do not hesitate to mention this product! Thanks.
It is true that in game development, STL is not used. In spite of what certain people always rush to claim, they also never use Java or C# or other managed languages.
I’m not talking about small X-Box Live Arcade downloadable games or web browser games, or such things. I’m talking about high-end development in AAA games.
They don’t use STL. However, they do use their own custom implementations that look a lot like STL. There will be smart-arrays, there will be hash tables, there will be smart pointers, they just won’t be STL.
Consoles have some performance characteristics that are very different from PCs. Even game projects that exclusively target PC are usually using codebases that have been used for console projects in the past. A lot of tweaking goes into making the basic template structures work as desired.
Most game studios also want code that they can adapt to other platforms. Locking into an implementation from MS/Sony/Nintendo makes for a lot more pain when it comes time to port the game to a new platform. The provided template libraries (which aren’t necessarily STL to start with) are often less than stellar. At least they are that way early in the hardware cycle when a studio is ironing out the engine they plan to keep using for the next five years.
At the studios I’ve worked at, I’ve certainly seen a fair degree of “not-built-here” attitude to dismiss third party code. Sometimes it’s justified, sometimes it’s not. In the case of basic data structure templates, it typically is.
As for your second question, assembler is occasionally used. But only in isolated situations where a large volume of math needs to happen very frequently. An entire engine might contain two or three smallish files of asm blocks.