A field that ramps lo → hi as coord[axis] goes a → b, clamped to the endpoint band outside [a, b]. axis is 0 (x), 1 (y), or 2 (z).
lo → hi
coord[axis]
a → b
[a, b]
axis
Optional
A field that ramps
lo → hiascoord[axis]goesa → b, clamped to the endpoint band outside[a, b].axisis 0 (x), 1 (y), or 2 (z).