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#define ALLEGRO_UNSTABLE
#include <allegro5/allegro.h>
#include <allegro5/allegro_image.h>
#include <allegro5/allegro_font.h>
#include <stdlib.h>
#include <math.h>
#include "common.c"
#define FPS 60
static ALLEGRO_BITMAP *load_bitmap(char const *filename)
{
ALLEGRO_BITMAP *bitmap = al_load_bitmap(filename);
if (!bitmap)
abort_example("%s not found or failed to load\n", filename);
return bitmap;
}
int main(int argc, char **argv)
{
ALLEGRO_TIMER *timer;
ALLEGRO_EVENT_QUEUE *queue;
ALLEGRO_DISPLAY *display;
ALLEGRO_BITMAP* mysha;
ALLEGRO_BITMAP* parrot;
ALLEGRO_BITMAP* targets[4];
ALLEGRO_BITMAP* backbuffer;
int w;
int h;
bool done = false;
bool need_redraw = true;
(void)argc;
(void)argv;
if (!al_init()) {
abort_example("Failed to init Allegro.\n");
}
if (!al_init_image_addon()) {
abort_example("Failed to init image addon.\n");
}
init_platform_specific();
mysha = load_bitmap("data/mysha.pcx");
parrot = load_bitmap("data/obp.jpg");
w = al_get_bitmap_width(mysha);
h = al_get_bitmap_height(mysha);
display = al_create_display(2 * w, 2 * h);
if (!display) {
abort_example("Error creating display.\n");
}
if (!al_install_keyboard()) {
abort_example("Error installing keyboard.\n");
}
/* Set up blend modes once. */
backbuffer = al_get_backbuffer(display);
targets[0] = al_create_sub_bitmap(backbuffer, 0, 0, w, h );
al_set_target_bitmap(targets[0]);
al_set_bitmap_blender(ALLEGRO_DEST_MINUS_SRC, ALLEGRO_SRC_COLOR, ALLEGRO_DST_COLOR);
targets[1] = al_create_sub_bitmap(backbuffer, w, 0, w, h );
al_set_target_bitmap(targets[1]);
al_set_bitmap_blender(ALLEGRO_ADD, ALLEGRO_SRC_COLOR, ALLEGRO_DST_COLOR);
al_set_bitmap_blend_color(al_map_rgb_f(0.5, 0.5, 1.0));
targets[2] = al_create_sub_bitmap(backbuffer, 0, h, w, h );
al_set_target_bitmap(targets[2]);
al_set_bitmap_blender(ALLEGRO_SRC_MINUS_DEST, ALLEGRO_SRC_COLOR, ALLEGRO_DST_COLOR);
targets[3] = al_create_sub_bitmap(backbuffer, w, h, w, h );
al_set_target_bitmap(targets[3]);
al_set_bitmap_blender(ALLEGRO_DEST_MINUS_SRC, ALLEGRO_INVERSE_SRC_COLOR, ALLEGRO_DST_COLOR);
timer = al_create_timer(1.0 / FPS);
queue = al_create_event_queue();
al_register_event_source(queue, al_get_keyboard_event_source());
al_register_event_source(queue, al_get_timer_event_source(timer));
al_register_event_source(queue, al_get_display_event_source(display));
al_start_timer(timer);
while (!done) {
ALLEGRO_EVENT event;
if (need_redraw) {
int i;
al_set_target_bitmap(backbuffer);
al_draw_bitmap(parrot, 0, 0, 0);
for (i = 0; i < 4; i++) {
/* Simply setting the target also sets the blend mode. */
al_set_target_bitmap(targets[i]);
al_draw_bitmap(mysha, 0, 0, 0);
}
al_flip_display();
need_redraw = false;
}
while (true) {
al_wait_for_event(queue, &event);
switch (event.type) {
case ALLEGRO_EVENT_KEY_CHAR:
if (event.keyboard.keycode == ALLEGRO_KEY_ESCAPE)
done = true;
break;
case ALLEGRO_EVENT_DISPLAY_CLOSE:
done = true;
break;
case ALLEGRO_EVENT_TIMER:
need_redraw = true;
break;
}
if (al_is_event_queue_empty(queue))
break;
}
}
return 0;
}
/* vim: set sts=3 sw=3 et: */
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