#define MACH 343 // speed of sound in m/s
/*#define ds 0.3 // distance between sensors in m (should be in equilateral triangle shape)*/
#define ns_to_s(x) (x / 1000000000) // convert nanoseconds to seconds
#define pi 3.14159265358979323846 // ... pi. Like the constant, y'know?


/* relative positions of sensors */
#define TOP 0
#define LEFT 1
#define RIGHT 2

#define TOPLEFT 0
#define LEFTRIGHT 1
#define RIGHTTOP 2


typedef struct {
	double x;
	double y;
} coord;

typedef struct {
    int sensor_id[3];
    PaStream *sensor_stream[2];
    double ds;
    int16_t sensor_data[2];
	int16_t threshold;
} sonar_config;

void sonar_init (void);
void sonar_listdev (void);
void sonar_getloc ( coord *loc, sonar_config conf );
int sonar_coord_cmp (coord a, coord b);