The sense of rotation from the x axis to the y axis, as seen from
where the recording was made. atan2(y, x) counts counter-clockwise, so
a frame stored the other way up reports the mirror of the angle a
counter_clockwise frame would give for the same physical heading.
Derived from get_axis_directions() rather than recorded, so it cannot
go on claiming a sense the axes no longer have.
Value
"clockwise", "counter_clockwise", or "unknown" when the two
axes are not both declared or do not span the view.
Examples
af <- example_aniframe(n_obs = 3, n_individuals = 1, n_keypoints = 1)
# An image-plane frame counts angles clockwise
af <- set_axis_directions(af, c(x = "right", y = "down"))
get_angle_direction(af)
#> [1] "clockwise"