#define DEBUG
#ifdef DEBUG
printf("a: (%.3f, %.3f, %.3f, %.3f, %.3f), b: (%.3f, %.3f, %.3f, %.3f, %.3f)\n", a_x1, a_y1, a_x2, a_y2, a_angle,
b_x1, b_y1, b_x2, b_y2, b_angle);
printf("center a: (%.3f, %.3f), b: (%.3f, %.3f)\n", center_a.x, center_a.y, center_b.x, center_b.y);
#endif