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#include <allegro5/allegro.h>
#include <allegro5/allegro_image.h>
#include <allegro5/allegro_primitives.h>
#include <stdlib.h>
#include <math.h>
#include "common.c"
#define FPS 60
struct Example {
ALLEGRO_DISPLAY *display;
ALLEGRO_BITMAP *glyphs[2];
ALLEGRO_BITMAP *sub;
int i;
int p;
} example;
/* Draw the parent bitmaps. */
static void draw_glyphs(void)
{
int x = 0, y = 0;
al_clear_to_color(al_map_rgb_f(0, 0, 0));
al_draw_bitmap(example.glyphs[0], 0, 0, 0);
al_draw_bitmap(example.glyphs[1], 0, 32 * 6, 0);
if (example.p == 1)
y = 32 * 6;
x += al_get_bitmap_x(example.sub);
y += al_get_bitmap_y(example.sub);
al_draw_filled_rectangle(x, y,
x + al_get_bitmap_width(example.sub),
y + al_get_bitmap_height(example.sub),
al_map_rgba_f(0.5, 0, 0, 0.5));
}
static void redraw(void)
{
int i;
draw_glyphs();
/* Here we draw example.sub, which is never re-created, just
* re-parented.
*/
for (i = 0; i < 8; i++) {
al_draw_scaled_rotated_bitmap(example.sub, 0, 0,
i * 100, 32 * 6 + 33 * 5 + 4,
2.0, 2.0, ALLEGRO_PI / 4 * i / 8, 0);
}
}
static void update(void)
{
/* Re-parent out sub bitmap, jumping from glyph to glyph. */
int i;
example.i++;
i = (example.i / 4) % (16 * 6 + 20 * 5);
if (i < 16 * 6) {
example.p = 0;
al_reparent_bitmap(example.sub, example.glyphs[0],
(i % 16) * 32, (i / 16) * 32, 32, 32);
}
else {
example.p = 1;
i -= 16 * 6;
al_reparent_bitmap(example.sub, example.glyphs[1],
(i % 20) * 37, (i / 20) * 33, 37, 33);
}
}
static void init(void)
{
/* We create out sub bitmap once then use it throughout the
* program, re-parenting as needed.
*/
example.sub = al_create_sub_bitmap(example.glyphs[0], 0, 0, 32, 32);
}
int main(int argc, char **argv)
{
ALLEGRO_TIMER *timer;
ALLEGRO_EVENT_QUEUE *queue;
int w = 800, h = 600;
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 IIO addon.\n");
}
al_init_primitives_addon();
init_platform_specific();
al_set_new_bitmap_flags(ALLEGRO_MIN_LINEAR | ALLEGRO_MAG_LINEAR);
al_set_new_display_flags(ALLEGRO_RESIZABLE);
example.display = al_create_display(w, h);
if (!example.display) {
abort_example("Error creating display.\n");
}
if (!al_install_keyboard()) {
abort_example("Error installing keyboard.\n");
}
example.glyphs[0] = al_load_bitmap("data/font.tga");
if (!example.glyphs[0]) {
abort_example("Error loading data/font.tga\n");
}
example.glyphs[1] = al_load_bitmap("data/bmpfont.tga");
if (!example.glyphs[1]) {
abort_example("Error loading data/bmpfont.tga\n");
}
init();
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(
example.display));
al_start_timer(timer);
while (!done) {
ALLEGRO_EVENT event;
w = al_get_display_width(example.display);
h = al_get_display_height(example.display);
if (need_redraw && al_is_event_queue_empty(queue)) {
redraw();
al_flip_display();
need_redraw = false;
}
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_DISPLAY_RESIZE:
al_acknowledge_resize(event.display.source);
break;
case ALLEGRO_EVENT_TIMER:
update();
need_redraw = true;
break;
}
}
return 0;
}
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