Question

in my code I have a struct for bitmaps.

struct bat 
{
 float x;
 float y;
 ALLEGRO_BITMAP *bmp;
};

There are functions that handle loading and drawing the bitmaps to screen.

ALLEGRO_DISPLAY *display;

bool init_display(void)
{
   puts("-- initializing display. --");
   display = al_create_display(display_width, display_height);
   if(display)
   {
     al_clear_to_color(al_map_rgb(0,0,0));
     queue = al_create_event_queue();
     al_register_event_source(queue, al_get_display_event_source(display));
     if(init_objects()){return true; puts("-- display initialized. --");}
     else return false;
   }
   else return false;
}

bool create_bat(struct bat *bat, float x_coord, float y_coord, const char *path)
{   
    puts("-- creating bat. --");
    bat->x = x_coord;
    bat->y = y_coord; 
    bat->bmp = al_load_bitmap(path);
    if(bat->bmp){puts("-- bat created. --"); return true;}
    else return false;
}

struct bat bat; 

bool init_objects(void)
{
   puts("-- initializing objects. --");
   if(al_init_image_addon())
   {
      al_set_new_bitmap_flags(ALLEGRO_MEMORY_BITMAP);
      al_set_target_backbuffer(display);
      if(!create_bat(&bat, 0, 0, "img.jpg"))
      { puts("-- creating bat failed. --"); return false;}
      puts("-- objects initialized. --"); 
      return true;
   }
else return false;
}

I’m always getting this output when I use an absolute path for the bitmap to load or a relative one.

-- initializing display. --
-- initializing objects. --
-- creating bat. --
-- creating bat failed. --

What am I doing wrong? Thanks. (OS: Ubuntu 10.10)

Answer 1

I think you need to install external dependencies to load a jpg image and link your executable with it. The manual says:

The following types are built into the Allegro image addon and guaranteed to be available: BMP, PCX, TGA. Every platform also supports JPEG and PNG via external dependencies.

See this: http://alleg.sourceforge.net/a5docs/5.0.3/image.html

You would need the libjpeg and libjpeg-dev addon if you still do not have. Find some information about the different addons here:

http://wiki.allegro.cc/index.php?title=Install_Allegro5_From_SVN/Linux/Debian