When a game requires “Microsoft Visual C++ (year)” or “DirectX (number)” to be installed along with the game itself, what are those things and how does the game use them to work?

Question

Often when installing a game through a digital storefront, after the game has downloaded and installed, but before rubbing for the first time, it will download various files titled “Visual c++ library 2008” etc, even if previous games have installed them. I suppose the main things I’m wondering are; What are these things, why do the games need them to work, and why aren’t they included in the files Steam/Epic/Uplay downloads when you install the game?

In: Technology

Answer 1

Back in the day before Windows, PC’s could (mostly) only run one thing at a time. Each program took up the entire screen, you wanted to switch, you had to stop one program and start the next. This was a serious limitation, but it was great for games. They could take over your whole computer, use every last resource, and run really fast.

Then Windows came along and let you run multiple programs at once. Instead of sending commands directly to the computer, programs would send them to Windows and it would sort things out. That was fine for a word processor, but for graphically intensive programs sending every pixel update to Windows instead of directly to the graphics card could be painfully slow and make games unplayable. Instead, you would exit Windows (you could do that back then) in order to play your game, then return when you were done. Kind of a pain in the ass.

DirectX was Window’s solution to this. It is a library to allows programs like games to have direct access to the graphics card once again. However, graphics cards are constantly changing and games are constantly finding better ways to coax a little extra performance out of them, so DirectX libraries were constantly being updated. To avoid incompatibility issues, games found it easier to just include a late enough version of DirectX with their install.

C++ is a programming language many Windows programs are written in, and Visual C++ is Microsoft’s implementation of it. They added a library of functions many programs use, particularly when it comes to user interface elements. Those programs need that library installed on any machine where they will be executed.

Steam and similar services keep DirectX and other shared libraries up to date independently of the programs you download from them.