sfc_previous_point(BASE_R, c(0, 0), 0)
sfc_previous_point(BASE_R, c(0, 0), 90)
sfc_previous_point(BASE_R, c(0, 0), 180)
sfc_previous_point(BASE_R, c(1, 0), 0)
sfc_previous_point(BASE_R, c(1, 0), 90)
sfc_previous_point(BASE_R, c(1, 0), 180)
sfc_next_point(BASE_R, c(0, 0), 0)
sfc_next_point(BASE_R, c(0, 0), 90)
sfc_next_point(BASE_R, c(0, 0), 180)
sfc_next_point(BASE_R, c(1, 0), 0)
sfc_next_point(BASE_R, c(1, 0), 90)
sfc_next_point(BASE_R, c(1, 0), 180)
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