int m_trace;
struct {
double xd1,yd1,xd2,yd2; /* Coordinates of detector endpoints */
double xs1,ys1,xs2,ys2; /* Coordinates of source endpoints */
double angle; /* Starting angle */
int m_trace;
struct {
double xd1,yd1,xd2,yd2; /* Coordinates of detector endpoints */
double xs1,ys1,xs2,ys2; /* Coordinates of source endpoints */
double angle; /* Starting angle */