1. When asking for help, always say what the problem actually is. Is it not compiling? Is it crashing? Is it producing undesired results? If so, what are the desired results? Help people help you by telling them what to look for.

2. When posting code, put it in <code></code> tags. Use the edit button to add them.

bool Snake::collision()
    {
         for(int i=0; i<100;i++){
             if((x+1)==xPrevious[i] && y==yPrevious[i-1]){
                  return false;
                  }
             }
         
     }

Think about what you are doing - you are checking if x plus one is the same as any of the last 100 x values and the current y is the same as the yPrevious value one before the current (i) yPrevious value. Does that make sense?

Try storing your snake values in a std::list :

But you're still only checking if it moves up, and you don't know if it has. And, you're not checking the right index for the previous Y value (You should use i, not i - 1).

That's okay, I'll walk you through it.

A list is a C++ container template defined in the system header list and contained in the std namespace. This means to use it you will need to :

#include <list> // include the header that defines list
using std::list;// tell the compiler we will be using list to refer to std::list

To use a template, you need to tell it what type it will be using.

list<segment> body;// declares a list of segment objects named body

To iterate over a list, you need to use a list<TYPE>::iterator. iterators are just an efficient way to move back and forth over the objects contained in the list (or more generally, container).

For more information on the Standard Template Library containers (like list), take a look here :
http://www.sgi.com/tech/stl/index.html

And I actually made a typo. body.grow() doesn't exist - it is not a member of the list class. What I meant was that if the snake will grow on this update, then you should not erase the tail of the snake (which is stored at the beginning of the list). So, something more like this :

--growcounter;
bool grow = (growcounter == 0);
if (growcounter == 0) {growcounter = time_between_growth;}
if (!body.empty() && !grow) {
   body.erase(body.begin());
}

If you have any more questions or can't get it to work, post your errors here, and your questions too.

The segment structure can be declared anywhere before a class or function that uses it. This means it can go in a separate header, or in the same header as the one for your snake class, before you declare it.

Be specific with your problems.

If you don't know what printf does, you need to get yourself a C/C++ reference guide to look at. This one might be okay :
http://www.cplusplus.com/
http://www.cplusplus.com/reference/clibrary/

You'll want to iterate over the list when you check each segment in the body list against the head segment to find out if the snake ran over itself and died.

@Thomas,
Yeah, i could probably find the problem with google. but if it aint broken, dont fix it! And this allegro is working perfectly fine for me, and has all the functions i need

OT,
First of all, thanks for the help .
second off all:
I have no clue how to declare the grow member

But still it says that class std::list<........> 'has no member named 'grow';
Also ive added my project again, maybe somebody can see what im doing wrong there?

Ah oh ok, thx.
And the xdir and ydir are my snake x and y values rght?

I have no clue on how to do it anymore :s.

So what what you gave me:
An update function with variables update_counter and a set value time_til_next_update, I should declare this int's in my class i suppose.
This part of code i get, so my time till next update variable is basicly the speed if im correct?
Then the updateSnake, this one i dont get. It sets the tail values, right?
but i dont really get the grow (boolean) and the growCounter.
And how to use these functions. I think i should use the Update() function in my main, which will use the renamed Update_Snake (Move() ) function. But when do i have to use my move function then?

    void Snake::movePlayer()
    {
            clear_keybuf();
            
            if (key[KEY_UP]) moveUp();        
            else if (key[KEY_DOWN]) moveDown();    
            else if (key[KEY_RIGHT])moveRight();
            else if (key[KEY_LEFT])moveLeft();
            Draw();
}

Thanks for keeping so patient, and helping me so much! Much appreciated!

Owh btw, how can i do the drawing for the tail? just by reading out all the segments? (so in a for loop, like i did for the array tail)

Yeah, its the same idea .
Now i reworked my whole code, no errors. runs. But i cant seem to be able to move the snakes head.
Ive used your exact pieces, using this for the drawing:
textout_ex( buffer, font, "@", head.x, head.y, makecol( 255, 0, 0), makecol( 0, 0, 0) );
and in the constructor(int x, int y):

 head.x=x;
 head.y=y;

So it draws the initial position of the head. But does not change when pressing a key! =/

int main(){
    Setup setup(640,480);
    Snake snake(200,100);
    while ( !key[KEY_ESC] ){
        snake.CheckInputs();
        snake.Update();
        snake.Draw();
        rest(50);
    }    
    return 0;  
}

my main (i know using rest is not very good, ill change that later on).

It doesnt draw anything anymore now =/

Here it is .

I cant seem to attach the file :s.
And its not drawing no

http://www.2shared.com/file/rCTGYtr8/Try3.html