Create a new {@link Vector3i} with the first two components from the
given <code>v</code> and the given <code>z</code> and round using the given {@link RoundingMode}.
@param v
the {@link Vector2d} to copy the values from
@param z
the z component
@param mode
the {@link RoundingMode} to use
Create a new {@link Vector3i} with the first two components from the given <code>v</code> and the given <code>z</code> and round using the given {@link RoundingMode}.
@param v the {@link Vector2d} to copy the values from @param z the z component @param mode the {@link RoundingMode} to use