reader.get("radius", radius);
reader.get("speed", speed);
bbox.set_pos(Vector(start_position.x + cos(angle) * radius,
start_position.y + sin(angle) * radius));
reader.get("radius", radius);
reader.get("speed", speed);
bbox.set_pos(Vector(start_position.x + cos(angle) * radius,
start_position.y + sin(angle) * radius));