Offsets for a Chebyshev or Manhattan Ring

Returns the (dx, dy) offsets of cells at exact distance d from the origin under the chosen ring shape. The origin itself is excluded.

Usage

ring_offsets(d, ring_type = c("manhattan", "chebyshev"))

Arguments

d

Positive integer ring radius.

ring_type

Ring shape: "manhattan" (default; diamond ring) or "chebyshev" (square ring). See ring_offsets().

Value

Integer matrix with two columns - column 1 holds dx, column 2 holds dy - one row per cell on the ring.