Including functions and variables from a separate header and cpp file.

[Luke Welburn]

Hello

I'm a bit stuck and was wondering if anyone is willing to help.

What im trying to do is at the top of my main.cpp function is to include a file which contains all the global variables and functions in.

Unfortunately ive also got a separate class file which requires some of these global variables.

Im getting the following error:

1>c:\users\luke\desktop\pong\main.cpp(36): error C3861: 'init': identifier not found
1>c:\users\luke\desktop\pong\main.cpp(42): error C3861: 'load_files': identifier not found
1>c:\users\luke\desktop\pong\main.cpp(58): error C2065: 'event' : undeclared identifier

And this is part of my header file:

#ifndef	HEADER1_H
#define HEADER1_H

#include <iostream>

using namespace std;

SDL_Surface *load_image( std::string filename );

void apply_surface( int x, int y, SDL_Surface* source, SDL_Surface* destination, SDL_Rect* clip );

bool init();

bool load_files();

void clean_up();

#endif 

Which has the functions in the correct cpp file.

Ive included this header file into my class file and main.cpp file

Any help would be appreciated, thanks

[Disch]

Nothing is wrong with that header file (although you don't need/shouldn't have that "using namespace std" in there).

Show us your main.cpp file.

[Luke Welburn]

Here is my main.cpp file

//The headers
#include "SDL.h"
#include "SDL_image.h"
#include "SDL_ttf.h"
#include "Dot.h"
#include "Timer.h"
#include "header.h"
#include <sstream>
#include <string>

int main( int argc, char* args[] )
{


    //Quit flag
    bool quit = false;
	
	int frame = 0;
	bool cap = true;

    //The dot that will be used
    Dot myDot;

    //The frame rate regulator
    Timer fps;
	Timer update;

    //Initialize
    if( init() == false )
    {
        return 1;
    }

    //Load the files
    if( load_files() == false )
    {
        return 1;
    }

	update.start();

	//Start the frame timer
       fps.start();

    //While the user hasn't quit
    while( quit == false )
    {


        //While there's events to handle
        while( SDL_PollEvent( &event ) )
        {
			                //If enter was pressed
                if( event.key.keysym.sym == SDLK_RETURN )
                {
                    //Switch cap
                    cap = ( !cap );
                }
            //Handle events for the dot
            myDot.handle_input();

            //If the user has Xed out the window
            if( event.type == SDL_QUIT )
            {
                //Quit the program
                quit = true;
            }
        }

        //Move the dot
        myDot.move();

		apply_surface(0,0, background, screen);

		apply_surface( 0,0, sprite, screen );
		
        //Show the dot on the screen
  		myDot.show();

		        if( SDL_Flip( screen ) == -1 )
        {
            return 1;
        }

		frame++;
        //Update the screen

		 if( update.get_ticks() > 1000 )
        {
            //The frame rate as a string
            std::stringstream caption;

            //Calculate the frames per second and create the string
            caption << "Average Frames Per Second: " << frame / ( fps.get_ticks() / 1000.f );

            //Reset the caption
            SDL_WM_SetCaption( caption.str().c_str(), NULL );

            //Restart the update timer
            update.start();
        }


		        //Cap the frame rate
        if( (cap == true) && (fps.get_ticks() < 1000 / FRAMES_PER_SECOND ))
        {
            SDL_Delay( ( 1000 / FRAMES_PER_SECOND ) - fps.get_ticks() );
        }
    }

    //Clean up
    clean_up();

    return 0;
}

Thanks for the help.

[Disch]

is your file name header.h or header1.h?

main is including header.h but your first post suggests the name is header1.h

[Luke Welburn]

Yea they are named correctly.

Erm they were named correctly, but something went wrong as it said that I already had the header.h file.
So i started a new project and just pasted the code over.

Now the problem is, where should I put my variables that the header file require? Its not a class so I cant put them into a constructor.

1>c:\users\luke\documents\visual studio 2010\projects\sdl test\sdl test\main.cpp(74): error C2065: 'background' : undeclared identifier
1>c:\users\luke\documents\visual studio 2010\projects\sdl test\sdl test\main.cpp(74): error C2065: 'screen' : undeclared identifier
1>c:\users\luke\documents\visual studio 2010\projects\sdl test\sdl test\main.cpp(75): error C2065: 'sprite' : undeclared identifier
1>c:\users\luke\documents\visual studio 2010\projects\sdl test\sdl test\main.cpp(75): error C2065: 'screen' : undeclared identifier
1>c:\users\luke\documents\visual studio 2010\projects\sdl test\sdl test\main.cpp(80): error C2065: 'screen' : undeclared identifier

Also what should I do with my event? SDL_Event event;

Am I approaching this all wrong? The code was working when it was all in the main.cpp file, but I wanted to make things more organized and it seems to off just broken things lol.

Thanks for the help again :)

[Stewbond]

In your CPP file and H files, do a CTRL+F for "background", "screen" and "sprite". You'll see that you haven't defined it anywhere. These need to be of a specific type.

Also, I don't see SDL_Event anywhere in your code. I assume it must be in SDL.h or something, but you don't have SDL_Event event available to your CPP file. I'm surprised you don't have a compiler error for that too. Make sure that you have that somewhere.

[Stewbond]

Note: It's possible that you have these objects defined in another header file, however unless you use the extern keyword in the header and then re-define it in a cpp file somewhere, it will either not be available to this file, or it will create a compiliation error when you try to include that header twice.