Timers in allegro 5

Hey
I was looking into Allegro game library and I had a quick question about the timer system. Does it control the rate of change for the whole system? I thought the timer was more for timing things. One other thing: after I read through the tutorial, is this all I need to know in order to make a game? It seemed too easy to me (at least for creating a game) considering it takes 500+ pages to explain DirectX and over 1000 to explain Winapi (granted, it has a wide array of uses) . Maybe less is more. Thanks.
Post Merge: [time]1322531489[/time]
Oh and I almost forgot here is the tutorial I was referring to (Sorry :) ) : http://wiki.allegro.cc/index.php?title=Allegro_5_Tutorial/Bitmaps

timers usually trigger an event every interval, its up to you what happens when the event triggers.Theres a lot of explanation for directx for a reason, it is not a simple API. allegro might make things easy but you would have far more control by using raw directx.It is unlikely you will need to read even 1/10th of the winapi docs.

Okay so the FPS (Frames Per Second) are not determined by the timer, but by itself. And also, is FPS predefined in the allegro header? Thanks.

FPS should not be arbitarily defined, its the outcome of how much work needs doing to render each frame. less work = higher fps

#include <stdio.h>
#include <allegro5/allegro.h>
 
const float FPS = 60;
const int SCREEN_W = 640;
const int SCREEN_H = 480;
const int BOUNCER_SIZE = 32;
 
int main(int argc, char **argv){
   ALLEGRO_DISPLAY *display = NULL;
   ALLEGRO_EVENT_QUEUE *event_queue = NULL;
   ALLEGRO_TIMER *timer = NULL;
   ALLEGRO_BITMAP *bouncer = NULL;
   float bouncer_x = SCREEN_W / 2.0 - BOUNCER_SIZE / 2.0;
   float bouncer_y = SCREEN_H / 2.0 - BOUNCER_SIZE / 2.0;
   float bouncer_dx = -4.0, bouncer_dy = 4.0;
   bool redraw = true;
 
   if(!al_init()) {
      fprintf(stderr, "failed to initialize allegro!\n");
      return -1;
   }
 
   timer = al_create_timer(1.0 / FPS);
   if(!timer) {
      fprintf(stderr, "failed to create timer!\n");
      return -1;
   }
 
   display = al_create_display(SCREEN_W, SCREEN_H);
   if(!display) {
      fprintf(stderr, "failed to create display!\n");
      al_destroy_timer(timer);
      return -1;
   }
 
   bouncer = al_create_bitmap(BOUNCER_SIZE, BOUNCER_SIZE);
   if(!bouncer) {
      fprintf(stderr, "failed to create bouncer bitmap!\n");
      al_destroy_display(display);
      al_destroy_timer(timer);
      return -1;
   }
 
   al_set_target_bitmap(bouncer);
 
   al_clear_to_color(al_map_rgb(255, 0, 255));
 
   al_set_target_bitmap(al_get_backbuffer(display));
 
   event_queue = al_create_event_queue();
   if(!event_queue) {
      fprintf(stderr, "failed to create event_queue!\n");
      al_destroy_bitmap(bouncer);
      al_destroy_display(display);
      al_destroy_timer(timer);
      return -1;
   }
 
   al_register_event_source(event_queue, al_get_display_event_source(display));
 
   al_register_event_source(event_queue, al_get_timer_event_source(timer));
 
   al_clear_to_color(al_map_rgb(0,0,0));
 
   al_flip_display();
 
   al_start_timer(timer);
 
   while(1)
   {
      ALLEGRO_EVENT ev;
      al_wait_for_event(event_queue, &ev);
 
      if(ev.type == ALLEGRO_EVENT_TIMER) {
         if(bouncer_x < 0 || bouncer_x > SCREEN_W - BOUNCER_SIZE) {
            bouncer_dx = -bouncer_dx;
         }
 
         if(bouncer_y < 0 || bouncer_y > SCREEN_H - BOUNCER_SIZE) {
            bouncer_dy = -bouncer_dy;
         }
 
         bouncer_x += bouncer_dx;
         bouncer_y += bouncer_dy;
 
         redraw = true;
      }
      else if(ev.type == ALLEGRO_EVENT_DISPLAY_CLOSE) {
         break;
      }
 
      if(redraw && al_is_event_queue_empty(event_queue)) {
         redraw = false;
 
         al_clear_to_color(al_map_rgb(0,0,0));
 
         al_draw_bitmap(bouncer, bouncer_x, bouncer_y, 0);
 
         al_flip_display();
      }
   }
 
   al_destroy_bitmap(bouncer);
   al_destroy_timer(timer);
   al_destroy_display(display);
   al_destroy_event_queue(event_queue);
 
   return 0;
}

Now here is what I don't get from this code excerpt from the tutorial:

const float FPS = 60;

Ok, so when I play around with this, it changes how fast the bitmap/sprite moves on the screen.
but then here is where they loose me:

 timer = al_create_timer(1.0 / FPS);

I really don't get what they are doing .
Thanks

I think I get it. When you initialize the timer, it becomes the event que (ev) and then the next line tests the condition, and if it is true, it then initializes a certain routine . Thanks again loony
Sorry for not getting right away.