DirectDraw in C

[bcrew1375]

I've been trying for a while to get a simple DirectDraw program written in C to compile under MSVC++ 6.0. It refuses to compile this line:

DirectDrawCreateEx(NULL, &lpDD, IID_IDirectDraw7, NULL);

It gives me the following errors:

directdraw.c(5) : error C2115: 'function' : incompatible types
directdraw.c(5) : warning C4024: 'DirectDrawCreateEx' : different types for formal and actual parameter 3

Any ideas?

BTW, I've included ddraw.h, and I've added the ddraw.lib and dxguid.lib files.

[smcd]

I googled for "warning C4024: 'DirectDrawCreateEx' : different types for formal and actual parameter 3" without the quotes and got 2 results, both from gamedev.net, and both saying the below. Give it a try

http://www.gamedev.net/community/for...topic_id=34452
http://www.gamedev.net/community/for...topic_id=85221

DirectDrawCreateEx(NULL, (VOID**)&lpDD, IID_IDirectDraw7, NULL); should be changed to:

DirectDrawCreateEx(NULL, (VOID**)&lpDD, &IID_IDirectDraw7, NULL);

[bcrew1375]

Thanks, seth. That is weird though. I swear to you I found both of the pages you just linked before, I tried exactly what they said and it refused to work. Yet when you suggested it just now and I tried it, it magically works. What's the deal O_o?

[smcd]

Weird indeed, but glad it works now

[blueshogun96]

Yeah, your problem was the fact that you didn't have a '&' in front of your GUID. I forgot why, but when you are using COM in C, you need to do that for EVERY GUID you use, not just with DirectDrawCreateEx, but also with IUnknown::QueryInterface. I am a die-hard, strait C, DirectDraw programmer myself, so I have had my fair share of this.

[Poobah]

Would someone be able to post a guide of some sort that explains how to actually use Directdraw in C?

[bcrew1375]

I've looked for a guide, but I have yet to find one. For the functions I've used so far, I had to make the pointer in front of the function the first argument in the parentheses and then add "IDirectDraw7_" where the pointer was.

So, as far as I can tell:

lpDD->SetCooperativeLevel(hwnd, DDSCL_EXCLUSIVE | DDSCL_FULLSCREEN);

Would become something like this in C:

IDirectDraw7_SetCooperativeLevel(lpDD, hwnd, DDSCL_EXCLUSIVE | DDSCL_FULLSCREEN);

[Doomulation]

One question though:
Why use C?

[ShizZy]

Because some people like C better, there needs no explanation further than that

Personally, I like to use C in a C++ programming enviroment. (By taking advantage of things like variable declarations at various points in a function, C++ libs, and on a rare occasion namespaces). For the most part though, my code is pretty straight C. Too many classes and such generally leads to fluff in my opinion, at least for emulator programming. (There is use else where though).

[bcrew1375]

One question though:
Why use C?

For me, I just don't like C++. It has too many things that I don't need, and it is easier for me to use C.