def _get_eyelink_clock_async(self):
"""
Retrieve time differenece between tracker timestamps and
current clock time upheld in the pygaze environment.
Note that this is not guaranteed to be a static time difference, the
clocks might run at different speeds. Therefore you should consider
running this function every time you utilize on this time difference.
Returns:
The tracker time minus the clock time
"""
return pylink.getEYELINK().trackerTime() - clock.time()
def _get_eyelink_clock_async(self):
"""
Retrieve time differenece between tracker timestamps and
current clock time upheld in the pygaze environment.
Note that this is not guaranteed to be a static time difference, the
clocks might run at different speeds. Therefore you should consider
running this function every time you utilize on this time difference.
Returns:
The tracker time minus the clock time
"""
return pylink.getEYELINK().trackerTime() - clock.time()
def wait_for_event(self, event):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.wait_for_event(): Recording "
"was not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
if self.eventdetection == 'native':
# since the link buffer was not have been polled, old data has
# accumulated in the buffer -- so ignore events that are old:
t0 = clock.time() # time of call
while True:
d = pylink.getEYELINK().getNextData()
if d == event:
float_data = pylink.getEYELINK().getFloatData()
# corresponding clock_time
tc = float_data.getTime() - self._get_eyelink_clock_async()
if tc > t0:
return tc, float_data
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
("Error in libeyelink.libeyelink.wait_for_event: eventcode %s "
"is not supported") % event)
return outcome
def wait_for_event(self, event):
"""See pygaze._eyetracker.baseeyetracker.BaseEyeTracker"""
if not self.recording:
raise Exception(
"Error in libeyelink.libeyelink.wait_for_event(): Recording "
"was not started before collecting eyelink data!")
if self.eye_used == None:
self.set_eye_used()
if self.eventdetection == 'native':
# since the link buffer was not have been polled, old data has
# accumulated in the buffer -- so ignore events that are old:
t0 = clock.time() # time of call
while True:
d = pylink.getEYELINK().getNextData()
if d == event:
float_data = pylink.getEYELINK().getFloatData()
# corresponding clock_time
tc = float_data.getTime() - self._get_eyelink_clock_async()
if tc > t0:
return tc, float_data
if event == 5:
outcome = self.wait_for_saccade_start()
elif event == 6:
outcome = self.wait_for_saccade_end()
elif event == 7:
outcome = self.wait_for_fixation_start()
elif event == 8:
outcome = self.wait_for_fixation_end()
elif event == 3:
outcome = self.wait_for_blink_start()
elif event == 4:
outcome = self.wait_for_blink_end()
else:
raise Exception(
("Error in libeyelink.libeyelink.wait_for_event: eventcode %s "
"is not supported") % event)
return outcome