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#include <allegro5/allegro5.h>
#include <allegro5/allegro_font.h>
#include <allegro5/allegro_primitives.h>
#include <stdlib.h>
#include <stdio.h>
#include <rb.h>
ALLEGRO_DISPLAY *
init_allegro_display(struct rb *rb)
{
if (!rb)
return NULL;
al_set_new_display_option(ALLEGRO_SAMPLE_BUFFERS, 1, ALLEGRO_SUGGEST);
al_set_new_display_option(ALLEGRO_SAMPLES, 8, ALLEGRO_SUGGEST);
al_set_new_bitmap_flags(ALLEGRO_MIN_LINEAR | ALLEGRO_MAG_LINEAR);
return al_create_display(rb->width, rb->height);
}
/*
* Allegro lib functions return 0 in case of error (or NULL), to make
* it compliant to Unix, return 0 if we succeed, non-zero otherwise
*/
int
initialize_allegro(struct rb **p)
{
struct rb *rb;
if (*p != NULL) {
printf("Allegro already initialized\n");
return 1;
}
rb = malloc(sizeof(struct rb));
if (!rb)
return 1;
rb->width = RB_WIDTH;
rb->height = RB_HEIGHT;
rb->fps = RB_FPS;
if (!al_init())
goto err_alloc;
if (!al_install_keyboard())
goto err_alloc;
rb->timer = al_create_timer(rb->fps);
if (!rb->timer)
goto err_alloc;
rb->event_queue = al_create_event_queue();
if (!rb->event_queue)
goto err_timer;
rb->font = al_create_builtin_font();
if (!rb->font)
goto err_event_queue;
rb->display = init_allegro_display(rb);
if (!rb->display)
goto err_font;
if (!al_init_primitives_addon())
goto err_display;
*p = rb;
return 0;
err_display:
al_destroy_display(rb->display);
err_font:
al_destroy_font(rb->font);
err_event_queue:
al_destroy_event_queue(rb->event_queue);
err_timer:
al_destroy_timer(rb->timer);
err_alloc:
printf("Couldn't initialize Allegro\n");
free(rb);
return 1;
}
void
shutdown_allegro(struct rb *rb)
{
al_destroy_display(rb->display);
al_destroy_font(rb->font);
al_destroy_event_queue(rb->event_queue);
al_destroy_timer(rb->timer);
free(rb);
}
void
register_events(struct rb *rb)
{
al_register_event_source(rb->event_queue,
al_get_keyboard_event_source());
al_register_event_source(rb->event_queue,
al_get_display_event_source(rb->display));
al_register_event_source(rb->event_queue,
al_get_timer_event_source(rb->timer));
}
void
start_game(struct rb *rb)
{
bool done = false;
bool redraw = true;
float x, y;
ALLEGRO_EVENT event;
x = 100;
y = 100;
al_start_timer(rb->timer);
while (1) {
al_wait_for_event(rb->event_queue, &event);
switch(event.type) {
case ALLEGRO_EVENT_TIMER:
redraw = true;
break;
case ALLEGRO_EVENT_KEY_DOWN:
/* fallthrough */
case ALLEGRO_EVENT_DISPLAY_CLOSE:
done = true;
break;
}
if (done)
break;
if (redraw && al_is_event_queue_empty(rb->event_queue)) {
al_clear_to_color(al_map_rgb(0, 0, 0));
al_draw_textf(rb->font, al_map_rgb(255, 255, 255),
0, 0, 0,
"X: %.1f Y: %.1f", x, y);
al_draw_filled_rectangle(x, y, x+10, y+10,
al_map_rgb(255, 0, 0));
al_flip_display();
redraw = false;
}
}
}
int
main(void)
{
int error;
struct rb *rb = NULL;
error = initialize_allegro(&rb);
if (error)
exit(EXIT_FAILURE);
register_events(rb);
start_game(rb);
shutdown_allegro(rb);
return 0;
}
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