Experiment with eye-tracking

Integration with Eyelink functionality makes programming experiments using eye-tracking simpler.

# Author: Eric Larson <larsoner@uw.edu>
#
# License: BSD (3-clause)

import numpy as np

import expyfun.analyze as ea
from expyfun import ExperimentController, EyelinkController, visual

print(__doc__)


with ExperimentController(
    "testExp",
    full_screen=True,
    participant="foo",
    session="001",
    output_dir=None,
    version="dev",
) as ec:
    el = EyelinkController(ec)
    ec.screen_prompt(
        "Welcome to the experiment!\n\nFirst, we will "
        "perform a screen calibration.\n\nPress a button "
        "to continue."
    )
    el.calibrate()  # by default this starts recording EyeLink data
    ec.screen_prompt(
        "Excellent! Now, follow the red circle around the edge "
        "of the big white circle.\n\nPress a button to "
        "continue"
    )

    # make some circles to be drawn
    radius = 7.5  # degrees
    targ_rad = 0.2  # degrees
    theta = np.linspace(np.pi / 2.0, 2.5 * np.pi, 200)
    x_pos, y_pos = radius * np.cos(theta), radius * np.sin(theta)
    big_circ = visual.Circle(
        ec,
        radius,
        (0, 0),
        units="deg",
        fill_color=None,
        line_color="white",
        line_width=3.0,
    )
    targ_circ = visual.Circle(
        ec, targ_rad, (x_pos[0], y_pos[0]), units="deg", fill_color="red"
    )
    fix_pos = (x_pos[0], y_pos[0])

    # start out by waiting for a 1 sec fixation at the start
    big_circ.draw()
    targ_circ.draw()
    screenshot = ec.screenshot()
    ec.identify_trial(ec_id="Circle", ttl_id=[0], el_id=[0])
    ec.start_stimulus()  # automatically stamps to EL
    if not el.wait_for_fix(fix_pos, 1.0, max_wait=5.0, units="deg"):
        print("Initial fixation failed")
    for ii, (x, y) in enumerate(zip(x_pos[1:], y_pos[1:])):
        targ_circ.set_pos((x, y), units="deg")
        big_circ.draw()
        targ_circ.draw()
        ec.flip()
        if not el.wait_for_fix([x, y], max_wait=5.0, units="deg"):
            print(f"Fixation {ii + 1} failed")
    ec.trial_ok()
    el.stop()  # stop recording to save the file
    ec.screen_prompt("All done!", max_wait=1.0)
    # eyelink auto-closes (el.close()) because it gets registered with EC

ea.plot_screen(screenshot)