passing arrays into functions by reference

for some reason, i can't figure out how to pass an array into a function properly.

here's the code where i'm encountering the error:

function declaration:

Code:

void initMapBuffer(map map1, CHAR_INFO &mapBuffer[]);

function body:

Code:

void initMapBuffer(map map1, CHAR_INFO &mapBuffer[])
{
 for (int y = 0; y < map1.max.Y; y++)
 {
  for (int x = 0; x < map1.max.X; x++)
  {
   mapBuffer[x + y * MAP_BUFFER_W].Char.AsciiChar = map1.tiles[x][y].symbol;
  }
 }
}

the map struct:

Code:

struct map
{
 tile tiles[MAP_MAX_X][MAP_MAX_Y];
 COORD max;
};

the tile struct

Code:

struct tile
{
 char symbol;
 char foreground, background;
};

please answer this question. I usually can figure these things out myself, but i'm stumped on this one. This piece of code is the cornerstone for my RPG, without it, i can't load maps and display them to the screen.

CHAR_INFO &mapBuffer[]

is an array of references, which isn't legal C++. You could try something like

CHAR_INFO (&mapBuffer)[SIZE]

if you're willing to commit a size to the arrays that'll be passed into the function, but as arrays are really passed by address they're passed by reference anyway so I see no reason not to just do

CHAR_INFO mapBuffer[]

oh.. i thought that you passed arrays by value if you didn't use the address of (&) operator. Alright, i'll try it out.

alright, now i'm getting an illegal operation when i execute it.

By default array's are passed by reference. All an array is, is a pointer to the first element in a series.

CHAR_INFO &mapBuffer[])

What excactly is CHAR_INFO?

Another thing you might try, silly, but, only cycle through half the array and see if it still crashes...

i'm using buffers to display the map for my roguelike to the screen, an array of CHAR_INFO stores what charactars and their attributes will go into each character slot in the buffer.

Originally posted by Aran Elus
oh.. i thought that you passed arrays by value if you didn't use the address of (&) operator. Alright, i'll try it out.

When you pass array's to a function, all you are really passing is the address of the first element. The compiler lets you use array notation ( arrayname[int] ) to make coding easier, If you change a value in the array in the function, the array from the calling function will be modifed as well.
So try this

void functionName( type * arrayname)

This will be ok if you know how big the array is going to be, or you could pass a size paramater along with the array name

void functionName( type * arrayname, int size)