int find_ball(Vec v) {
int num_balls = balls.size();
for (int i = 0; i < num_balls; i++) {
Ball p = balls.get2(i);
double dist = v.calc_dist(p.pos);
if (dist < RADIUS) {
// printf("found ball %d\n",i);
find_offset = p.pos.sub(dragged_vec);
// last_dragged_vec=v;
return i;
}
}
return -1;
}
