cpp-examples/allegro/example-02.c

/**
 * Example 02 - Allegro 5
 * Display image based on keyboard events.
 *
 * Juraj Michalek - http://georgik.sinusgear.com
 */

#include <allegro5/allegro5.h>
#include <allegro5/allegro_image.h>
#include <stdio.h>


int main()
{
	bool isStopSignal = false;
	ALLEGRO_EVENT_QUEUE *event_queue;
	ALLEGRO_DISPLAY *display;
	
	ALLEGRO_EVENT event;
	ALLEGRO_BITMAP *image;

	ALLEGRO_COLOR white = al_map_rgb_f(1.0, 1.0, 1.0);

	al_init();
	al_install_keyboard();
	al_init_image_addon();
	
	display = al_create_display(640, 480);
	if (!display)
	{
		return 2;
	}

	// Create Event queue
        event_queue = al_create_event_queue();

	// Register Keyboard to queue
        al_register_event_source(event_queue, al_get_keyboard_event_source());
	al_register_event_source(event_queue, al_get_display_event_source(display));

	// Clear screen
	al_clear_to_color(white);
	
	// Load and display image
	image = al_load_bitmap("smajlik.png");
	if (image == NULL)
	{
		printf("No bitmap.\n");
		return 1;
	}

	
	do {
		al_get_next_event(event_queue, &event);

		// Handle SPACE key - display smiley in case of pressed space
		// Clear screen in case of other key
		if (event.keyboard.keycode == ALLEGRO_KEY_SPACE) 
		{
			al_draw_bitmap(image, 10, 10, 0);
		} else {
			// Clear screen
			al_clear_to_color(white);
		}
		al_flip_display();

		// Handle ESC key
		if (event.keyboard.keycode == ALLEGRO_KEY_ESCAPE)
		{
			isStopSignal = true;
		}

	} while (!isStopSignal);

	// Release
	al_destroy_bitmap(image);
	al_uninstall_keyboard();
	al_uninstall_system();
	return 0;
}