passing pointer to change its value but stay still

Question

passing pointer to change its value but stay still

I am working on C++ with allegro library.

there is draw_tiles function.

void draw_tiles(def_sm         


        

Answer 1

Try this:

void loadTilemap(int i,BITMAP ** tileLayer){
    char c[128];
    sprintf(c,TILEPATHFORMAT,i);
    *tileLayer = load_bitmap(c,NULL);
}


loadTilemap(s_world->tilemap, &TileMap); 

The problem was that you pass the pointer to the BITMAP by value. To get the new pointer value out of loadTilemap, you have to pass it by reference.

EDIT:

On the other hand: why don't you just return the pointer to the newly created BITMAP?

BITMAP * loadTilemap(int i* tileLayer){
    char c[128];
    sprintf(c,TILEPATHFORMAT,i);
    return load_bitmap(c,NULL);
}

...

TileMap = loadTilemap(s_world->tilemap);