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#include <allegro5/allegro.h>
#include <allegro5/allegro_primitives.h>
#include "common.c"
#define MAX_TOUCHES 16
typedef struct TOUCH TOUCH;
struct TOUCH {
int id;
int x;
int y;
};
static void draw_touches(int num, TOUCH touches[])
{
int i;
for (i = 0; i < num; i++) {
int x = touches[i].x;
int y = touches[i].y;
al_draw_circle(x, y, 50, al_map_rgb(255, 0, 0), 4);
}
}
static int find_index(int id, int num, TOUCH touches[])
{
int i;
for (i = 0; i < num; i++) {
if (touches[i].id == id) {
return i;
}
}
return -1;
}
int main(int argc, char **argv)
{
int num_touches = 0;
bool quit = false;
bool background = false;
TOUCH touches[MAX_TOUCHES];
ALLEGRO_DISPLAY *display;
ALLEGRO_EVENT_QUEUE *queue;
ALLEGRO_EVENT event;
(void)argc;
(void)argv;
if (!al_init()) {
abort_example("Could not init Allegro.\n");
}
al_init_primitives_addon();
if (!al_install_touch_input()) {
abort_example("Could not init touch input.\n");
}
display = al_create_display(800, 600);
if (!display) {
abort_example("Error creating display\n");
}
queue = al_create_event_queue();
al_register_event_source(queue, al_get_touch_input_event_source());
al_register_event_source(queue, al_get_display_event_source(display));
while (!quit) {
if (!background && al_is_event_queue_empty(queue)) {
al_clear_to_color(al_map_rgb(255, 255, 255));
draw_touches(num_touches, touches);
al_flip_display();
}
al_wait_for_event(queue, &event);
switch (event.type) {
case ALLEGRO_EVENT_DISPLAY_CLOSE:
quit = true;
break;
case ALLEGRO_EVENT_TOUCH_BEGIN: {
int i = num_touches;
if (num_touches < MAX_TOUCHES) {
touches[i].id = event.touch.id;
touches[i].x = event.touch.x;
touches[i].y = event.touch.y;
num_touches++;
}
break;
}
case ALLEGRO_EVENT_TOUCH_END: {
int i = find_index(event.touch.id, num_touches, touches);
if (i >= 0 && i < num_touches) {
touches[i] = touches[num_touches - 1];
num_touches--;
}
break;
}
case ALLEGRO_EVENT_TOUCH_MOVE: {
int i = find_index(event.touch.id, num_touches, touches);
if (i >= 0) {
touches[i].x = event.touch.x;
touches[i].y = event.touch.y;
}
break;
}
case ALLEGRO_EVENT_DISPLAY_HALT_DRAWING:
background = true;
al_acknowledge_drawing_halt(event.display.source);
break;
case ALLEGRO_EVENT_DISPLAY_RESUME_DRAWING:
background = false;
al_acknowledge_drawing_resume(event.display.source);
break;
case ALLEGRO_EVENT_DISPLAY_RESIZE:
al_acknowledge_resize(event.display.source);
break;
}
}
return 0;
}
/* vim: set sts=3 sw=3 et: */
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