a game with Direct X you need the SDK, software development kit. The current
version 9 from MS won't work with VB6 if you have that though.
has the 8.1 SDK which will work with VB6.
The .net frqamework is for
internet use, don't confuse it with VB .net. Versions of the Microsoft
programming tools after 6 were given a tag .net, the .net framework si
seperate and shouldn't be an issue even for multiplayer.
tjhere is Direct Sound which offers more options such as stereo or 3D sound
positioning, as well as Direct Input for getting input from keyboard or game
controllers. Ignore Direct Music, it's mostly redundant these days since
everyone uses DirectSound for that. If you want multiplayer there's also
DX also has Direct Draw and Direct 3D for graphics, but we
don't need to worry about these.
As to how to modify an open source
game, you need to know the language and the syntax for any SDK or API used,
meaning you'll need to know Direct X in that language. If you mean Audio
Quake it'll probably be written in C or C++.
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