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/* This example displays a picture on the screen, with support for
* command-line parameters, multi-screen, screen-orientation and
* zooming.
*/
#include <stdio.h>
#include <stdlib.h>
#include "allegro5/allegro.h"
#include "allegro5/allegro_image.h"
#include "common.c"
int main(int argc, char **argv)
{
const char *filename;
ALLEGRO_DISPLAY *display;
ALLEGRO_BITMAP *bitmap;
ALLEGRO_TIMER *timer;
ALLEGRO_EVENT_QUEUE *queue;
bool redraw = true;
double zoom = 1;
double t0;
double t1;
/* The first commandline argument can optionally specify an
* image to display instead of the default. Allegro's image
* addon supports BMP, DDS, PCX, TGA and can be compiled with
* PNG and JPG support on all platforms. Additional formats
* are supported by platform specific libraries and support for
* image formats can also be added at runtime.
*/
if (argc > 1) {
filename = argv[1];
}
else {
filename = "data/mysha.pcx";
}
if (!al_init()) {
abort_example("Could not init Allegro.\n");
}
// Initializes and displays a log window for debugging purposes.
open_log();
/* The second parameter to the process can optionally specify what
* adapter to use.
*/
if (argc > 2) {
al_set_new_display_adapter(atoi(argv[2]));
}
/* Allegro requires installing drivers for all input devices before
* they can be used.
*/
al_install_mouse();
al_install_keyboard();
/* Initialize the image addon. Requires the allegro_image addon
* library.
*/
al_init_image_addon();
// Helper functions from common.c.
init_platform_specific();
// Create a new display that we can render the image to.
display = al_create_display(640, 480);
if (!display) {
abort_example("Error creating display\n");
}
al_set_window_title(display, filename);
// Load the image and time how long it took for the log.
t0 = al_get_time();
bitmap = al_load_bitmap(filename);
t1 = al_get_time();
if (!bitmap) {
abort_example("%s not found or failed to load\n", filename);
}
log_printf("Loading took %.4f seconds\n", t1 - t0);
// Create a timer that fires 30 times a second.
timer = al_create_timer(1.0 / 30);
queue = al_create_event_queue();
al_register_event_source(queue, al_get_keyboard_event_source());
al_register_event_source(queue, al_get_display_event_source(display));
al_register_event_source(queue, al_get_timer_event_source(timer));
al_start_timer(timer); // Start the timer
// Primary 'game' loop.
while (1) {
ALLEGRO_EVENT event;
al_wait_for_event(queue, &event); // Wait for and get an event.
if (event.type == ALLEGRO_EVENT_DISPLAY_ORIENTATION) {
int o = event.display.orientation;
if (o == ALLEGRO_DISPLAY_ORIENTATION_0_DEGREES) {
log_printf("0 degrees\n");
}
else if (o == ALLEGRO_DISPLAY_ORIENTATION_90_DEGREES) {
log_printf("90 degrees\n");
}
else if (o == ALLEGRO_DISPLAY_ORIENTATION_180_DEGREES) {
log_printf("180 degrees\n");
}
else if (o == ALLEGRO_DISPLAY_ORIENTATION_270_DEGREES) {
log_printf("270 degrees\n");
}
else if (o == ALLEGRO_DISPLAY_ORIENTATION_FACE_UP) {
log_printf("Face up\n");
}
else if (o == ALLEGRO_DISPLAY_ORIENTATION_FACE_DOWN) {
log_printf("Face down\n");
}
}
if (event.type == ALLEGRO_EVENT_DISPLAY_CLOSE)
break;
/* Use keyboard to zoom image in and out.
* 1: Reset zoom.
* +: Zoom in 10%
* -: Zoom out 10%
* f: Zoom to width of window
*/
if (event.type == ALLEGRO_EVENT_KEY_CHAR) {
if (event.keyboard.keycode == ALLEGRO_KEY_ESCAPE)
break; // Break the loop and quite on escape key.
if (event.keyboard.unichar == '1')
zoom = 1;
if (event.keyboard.unichar == '+')
zoom *= 1.1;
if (event.keyboard.unichar == '-')
zoom /= 1.1;
if (event.keyboard.unichar == 'f')
zoom = (double)al_get_display_width(display) /
al_get_bitmap_width(bitmap);
}
// Trigger a redraw on the timer event
if (event.type == ALLEGRO_EVENT_TIMER)
redraw = true;
// Redraw, but only if the event queue is empty
if (redraw && al_is_event_queue_empty(queue)) {
redraw = false;
// Clear so we don't get trippy artifacts left after zoom.
al_clear_to_color(al_map_rgb_f(0, 0, 0));
if (zoom == 1)
al_draw_bitmap(bitmap, 0, 0, 0);
else
al_draw_scaled_rotated_bitmap(
bitmap, 0, 0, 0, 0, zoom, zoom, 0, 0);
al_flip_display();
}
}
al_destroy_bitmap(bitmap);
close_log(false);
return 0;
}
/* vim: set sts=4 sw=4 et: */
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