void addToGrid(Actor actor) {
grid[actor.x()][actor.y()].actors.add(actor);
}
void removeFromGrid(Actor actor) {
grid[actor.x()][actor.y()].actors.remove(actor);
}
/**
* 添加角色到Layer
*
* @param object
*/
public void addObject(Actor object) {
if (isClose) {
return;
}
addObject(object, object.x(), object.y());
}