If I was writing a game engine and wanted to be able to load custom sprites how could I pass it to the load_bitmap() function? i.e. void GameEngine::Get_Sprites( ~Pass a String~ ) { BITMAP *~passed string~ = load_bitmap("~passed string~.EXTENSION", NULL); } Or maybe there is a better way? Thanks :) I guess what is confusing me are those quote marks.

That assumes hardcoding though.

Say I set this up.

ex of output.

"What file would you like to display?"
_
Repsonse = title
What is the files extension?
_
response = .bmp
_
~display title.bmp~

I want something like.

void GameEngine::Get_Sprites(std::string1, std::string2) {
BITMAP *std::string1 = load_bitmap("std::string1, std::string2", NULL);
}

I don't know how to pass it though, the file name is in quotes, so it wouldn't recognize a variable. :-/

Is your problem that you need to pass a character array to load_bmp instead of a string? Because that's what the c_str() function does to strings. So you can do this:

std::string userInput;
cout << "Please enter the filename (with extension) to load: ";
cin >> userInput;
BITMAP* map = load_bmp(userInput.c_str(), NULL);

I'm not especially familiar with using bitmaps, so my syntax may be off. I'm also not certain what your "Get_Sprites" function is supposed to do. What are its arguments? It evidently doesn't return anything because it's a void function, so what does it do?

From what i see, the OP tries to create new variables at runtime

Quote:
void GameEngine::Get_Sprites(std::string1, std::string2) {
BITMAP *std::string1 = load_bitmap("std::string1, std::string2", NULL);
}

noticed the std::string1 ?
it is impossible to create new named variables at runtime like this. The only thing i know that could do what you want is using an

std::map<std::string, BITMAP *>

more on std::map (msdn.microsoft.com)

hope that helps !
matchu

ah, I get what that function does now thank you.

the function would load my bitmaps at the initialization of the program and allow me to load more at a later time if wanted.. or reuseable code.

for instance.. let me see if i have this understood.





usage:


Well.. I thought I knew where I was going but I don't understand stdlib string functions very well. How would I go about concatenating them?

Well anyway that is the idea of the function.

file_name.c_str() = load_bitmap(concat.c_str(), NULL);

c_str() returns a constant value, not a variable you can assign to. First and foremost, your code is incorrect C++, so whatever you're doing, let's get it in general terms and then code the algorithm from there, because what you've got now is just plain flat-out impossible. You can assign to file_name, but not file_name.c_str(). The filename usually already has the file extension on it, but if you really need to add it, it's just file_name += ".bmp".

If you want to be able to load bitmaps and remember their filenames as well to display them, you could make a class consisting of a bitmap pointer and a string. You could also make a std::vector or std::list of them if you plan on creating a variable number of them on the fly. You could also store them in a std::map, using the filename for a key and the bitmap for the value. It all works, depending on what exactly you're driving at. But the above posters are correct; you can't just make new variables at runtime. That's what arrays and (better yet) container classes are for.

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So more like..





[Edited by - Lempface on June 7, 2006 6:54:55 PM]