The ability of engines like Bevy to automatically schedule dependencies and multithread systems, which relies on Rust's strictness around mutability, is a big advantage. Speaking as someone who's spent a long time looking at Bevy profiles, the increased parallelism really helps.
Of course, you can do job queuing systems in C++ too. But Rust naturally pushes you toward the more parallel path with all your logic. In C++ the temptation is to start sequential to avoid data races; in systems like Bevy, you start parallel to begin with.
Aside from a physics simulation, I'm curious as to what you think would be a positive cost benefit from that level of multithreading for the majority of game engines. Graphical pipelines take advantage of the concept but offload as much work as possible to the GPU.
What I have experienced is that C++ classes with inheritance are good at modeling objects in a game at first, when you are just starting and the hierarchy is super simple. Afterwards, it isn’t a good match. To can try to hack around this in several ways, but the short version of it is that if your game isn’t very simple you are better off starting with an Entity Component System setup. It will be more cumbersome to use than the language-provided features at first, but the lines cross very quickly.
Hmm no not really in my experience. Even the old "Entities and Components" system in Unity was better, because it allowed to compose GameObject behaviour by attaching Component objects, and this system was often replicated in C++ code bases until it "evolved" into ECS.
This is how I feel about golang and systems programming. The strong concurrency primitives and language simplicity make it easier to write and reason about concurrent code. I have to maintain some low level systems in python and the language is such a worse fit for solving those problems.
Yeah, OOP makes sense for games. The language will matter a bit for which one takes off, but anything will work given enough support. Like, Python doesn't inherently make a lot of sense for data processing or AI, but it's good enough.
OOP kind of goes out the window when people start using entity component systems. Of course, like the author, I'm not sure I'll need ECS since I'm not building a AAA game.
To be clear, the reason why Python is so popular for data wrangling (including ML/AI) is not due to the language itself. It is due to the popular extensions (libraries) exclusively written in C & C++! Without these libraries, no one would bother with Python for these tasks. They would use C++, Java, or .NET. Hell, even Perl is much faster than Python for data processing using only the language and not native extensions.
Disagree the adoption of C++ was more about Moore's law than ecosystem, although having compilers that were beginning to not be completely rubbish also helped.
Also C++ could be adopted incrementally by C developers. You could use it as “C with classes”, or just use operator overloading to make vector math more tolerable, or whatever subset that you happened to like.
So there’s really three forces at play in making C++ the standard:
1) The Microsoft ecosystem. They literally stopped supporting C by not adopting the C99 standard in their compiler. If you wanted any modern convenience, you had to compile in C++ mode. New APIs like Direct3D were theoretically accessible from C (via COM) but in practice designed for C++.
2) Better compilers and more CPU cycles to spare. You could actually count on the compiler to do the right thing often enough.
3) Seamless gradual adoption for C developers.
Rust has a good compiler, but it lacks that big ticket ecosystem push and is not entirely trivial for C++ developers to adopt.
Theoretically accessible describes the experience of trying to use D3D from C very well!
Was trying to use it with some kind of gcc for windows. The C++ part was still lacking some required features, so it was advised to use D3D from C instead C++. There were some helper macros, but overall I was glad when Microsoft started to release their Express (and later Community) Editions of Visual Studio.
I worked on many of Activision's games 1995-2000 and C++ was the overwhelming choice of programming language for PC games. C was more common for console. In 1996 the quality of MSFT IDE/ Compiler, plus the CPUs available at the time was such that it could take an hour to compile a big game. By 1998 it was a few minutes. As I recall I think MSFT purchased another companies compiler and that really changed Visual Studio.
I was a developer on the Microsoft C++ compiler team from 1991 to 2006. We definitely didn't purchase someone else's compiler in that time. We looked at the EDG front end at various times but never moved over to it while I was there.
Perhaps the speed-up you remember had something to do with the switch-over from 16 bits to 32, which would have been the early to mid 90s. Or you're thinking of Microsoft's C compiler starting from Lattice C, back in the 80s before my time. There was also a lot of work done on pre-compiled headers to speed compilation in the latter half of the 90s (including some that I was responsible for).
Kind of both in my opinion. But rust is bringing nothing to the table that games need.
At best rust fixes crash bugs and not the usual logic and rendering bugs that are far more involved and plague users more often.
The ability of engines like Bevy to automatically schedule dependencies and multithread systems, which relies on Rust's strictness around mutability, is a big advantage. Speaking as someone who's spent a long time looking at Bevy profiles, the increased parallelism really helps.
Of course, you can do job queuing systems in C++ too. But Rust naturally pushes you toward the more parallel path with all your logic. In C++ the temptation is to start sequential to avoid data races; in systems like Bevy, you start parallel to begin with.
Aside from a physics simulation, I'm curious as to what you think would be a positive cost benefit from that level of multithreading for the majority of game engines. Graphical pipelines take advantage of the concept but offload as much work as possible to the GPU.
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"Fearless concurrency"
C++ classes with inheritance are a pretty good match for objects in a 3D (or 2D) world, which is why C++ became popular with 3D game programmers.
This is not at all my experience.
What I have experienced is that C++ classes with inheritance are good at modeling objects in a game at first, when you are just starting and the hierarchy is super simple. Afterwards, it isn’t a good match. To can try to hack around this in several ways, but the short version of it is that if your game isn’t very simple you are better off starting with an Entity Component System setup. It will be more cumbersome to use than the language-provided features at first, but the lines cross very quickly.
I like the Javascript way of objects just having fully mutable keys/values like dictionaries, with no inheritance or static typing.
Hmm no not really in my experience. Even the old "Entities and Components" system in Unity was better, because it allowed to compose GameObject behaviour by attaching Component objects, and this system was often replicated in C++ code bases until it "evolved" into ECS.
This is how I feel about golang and systems programming. The strong concurrency primitives and language simplicity make it easier to write and reason about concurrent code. I have to maintain some low level systems in python and the language is such a worse fit for solving those problems.
Yeah, OOP makes sense for games. The language will matter a bit for which one takes off, but anything will work given enough support. Like, Python doesn't inherently make a lot of sense for data processing or AI, but it's good enough.
OOP kind of goes out the window when people start using entity component systems. Of course, like the author, I'm not sure I'll need ECS since I'm not building a AAA game.
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To be clear, the reason why Python is so popular for data wrangling (including ML/AI) is not due to the language itself. It is due to the popular extensions (libraries) exclusively written in C & C++! Without these libraries, no one would bother with Python for these tasks. They would use C++, Java, or .NET. Hell, even Perl is much faster than Python for data processing using only the language and not native extensions.
Python makes sense because of accessibility and general comfort for relatively small code bases with big data sets.
Those data scientists at least from my experience are more into math/business than interested in most efficient programming.
Or at least that was the situation at first and it sticked.
Disagree the adoption of C++ was more about Moore's law than ecosystem, although having compilers that were beginning to not be completely rubbish also helped.
Also C++ could be adopted incrementally by C developers. You could use it as “C with classes”, or just use operator overloading to make vector math more tolerable, or whatever subset that you happened to like.
So there’s really three forces at play in making C++ the standard:
1) The Microsoft ecosystem. They literally stopped supporting C by not adopting the C99 standard in their compiler. If you wanted any modern convenience, you had to compile in C++ mode. New APIs like Direct3D were theoretically accessible from C (via COM) but in practice designed for C++.
2) Better compilers and more CPU cycles to spare. You could actually count on the compiler to do the right thing often enough.
3) Seamless gradual adoption for C developers.
Rust has a good compiler, but it lacks that big ticket ecosystem push and is not entirely trivial for C++ developers to adopt.
I'd say Rust does have that big ticket ecosystem push. Microsoft has been embracing Rust lately, with things like official Windows bindings [1].
The bigger problem is just inertia: large game engines are enormous.
[1]: https://github.com/microsoft/windows-rs
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That description of problems bodes well for Zig
Theoretically accessible describes the experience of trying to use D3D from C very well!
Was trying to use it with some kind of gcc for windows. The C++ part was still lacking some required features, so it was advised to use D3D from C instead C++. There were some helper macros, but overall I was glad when Microsoft started to release their Express (and later Community) Editions of Visual Studio.
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not true anymore, c11 and c17 are either supported or coming
https://devblogs.microsoft.com/cppblog/c11-and-c17-standard-...
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I worked on many of Activision's games 1995-2000 and C++ was the overwhelming choice of programming language for PC games. C was more common for console. In 1996 the quality of MSFT IDE/ Compiler, plus the CPUs available at the time was such that it could take an hour to compile a big game. By 1998 it was a few minutes. As I recall I think MSFT purchased another companies compiler and that really changed Visual Studio.
I was a developer on the Microsoft C++ compiler team from 1991 to 2006. We definitely didn't purchase someone else's compiler in that time. We looked at the EDG front end at various times but never moved over to it while I was there.
Perhaps the speed-up you remember had something to do with the switch-over from 16 bits to 32, which would have been the early to mid 90s. Or you're thinking of Microsoft's C compiler starting from Lattice C, back in the 80s before my time. There was also a lot of work done on pre-compiled headers to speed compilation in the latter half of the 90s (including some that I was responsible for).
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I was a teenager at that point. I learnt C in the early 90s and C++ after 96 IIRC. Didn’t start professionally in games until 2004 though!