vrpn_Flock.h

#ifndef FLOCK_H
#define FLOCK_H
 
#include "vrpn_Configure.h" // for VRPN_API
#include "vrpn_Shared.h" // for timeval
#include "vrpn_Tracker.h" // for vrpn_Tracker_Serial
 
class VRPN_API vrpn_Connection;
 
// only 13 receivers allowed in normal addressing mode
#define VRPN_FLOCK_MAX_SENSORS 13
 
// This is a class which provides a server for an Ascension 
// Flock of Birds tracker.  The server will send out messages
// at whatever rate the flock of bird's stream mode feeds them.
// Default filtering is active.
// The timestamp is the time when the first character was read
// from the serial driver with "read".  No adjustment is currently
// made to this time stamp.
 
// Adelstein, et al, "Dynamic response of electromagnetic spatial
// displacement trackers", Presence 5(3) found that if all of the filters
// are turned off, and the time required to transport the data to the
// server is ignored, then the latency of the flock is about 2 ms for ori,
// 7.5 ms for pos for the 0-4hz range (ie, when the data is ready to leave
// the flock in stream mode, the pos is 7.5 ms old, and the ori is 2 ms
// old).  Later this data will be combined with the baud rate to provide a
// more accurate time stamp for certain flock modes.
 
// If this is running on a non-linux system, then the serial port driver
// is probably adding more latency -- see the vrpn README for more info.
 
// The FOB now doesn't need to be used in a chain starting with an Exteded
// range controller.  You may use the optionnal useERT to set whether this
// is the case or not.  Added by David Nahon, for Virtools VR Pack,
// david@z-a.net, support@virtools.com
 
class VRPN_API vrpn_Tracker_Flock: public vrpn_Tracker_Serial {
 
 public:
  vrpn_Tracker_Flock(char *name, vrpn_Connection *c, int cSensors=1,
 const char *port = "/dev/ttyd3", long baud = 38400,
 int fStreamMode = 1, int useERT=1, bool invertQuaternion = false, int active_hemisphere=HEMI_PLUSZ);
 virtual ~vrpn_Tracker_Flock();
 
 enum {HEMI_PLUSX, HEMI_MINUSX, HEMI_PLUSY, HEMI_MINUSY, HEMI_PLUSZ, HEMI_MINUSZ};
 
 protected:
 
 int activeHemisphere;
 
 virtual int get_report(void);
 virtual void send_report(void);
 virtual void reset();
 void printError(unsigned char uchErrCode, unsigned char uchExpandedErrCode);
 int checkError();
 int cSensors;
 int fStream;  // stream or polled mode
 int fGroupMode; // for get_report -- group report mode or individual
 
 int d_useERT; // do we have an extended range transmitter, this was the default
 bool d_invertQuaternion;  // Do we invert the Quaternion before returning it?
 
 // class members used to help with error recovery
 unsigned cResets;
 unsigned cSyncs;
 
 // class members used for statistics only
 int fFirstStatusReport;
 struct timeval tvLastStatusReport;
 int cReports;
 int cStatusInterval;
 double getMeasurementRate();
};
 
#endif