“…There have been numerous works on developing efficient and accurate algorithms for free-surface Green's functions, for the deepwater condition (e.g., [572,843]), and for the finite-depth water condition ( [572,120,458,473]). In general, the calculation strategies can be categorised into several types (in particular for finite-depth Green's function): (1) extracting slow-varying components from the Green function and using a Chebyshev or multi-dimensional polynomial method to approximate them (e.g., [572,120,473]); (2) applying asymptotic or power series expansions, such as eigenfunction expansions, rapid convergent series, or a combination with other numerical acceleration algorithms in different subregions (e.g., [634,448,456]); (3) decomposing the principal-value integral into two parts by subtracting a special term from the integrand and applying a direct Gauss-Laguerre quadrature to the numerical integration (e.g., [200,455]). In order to reduce the repeated effort in implementation of these algorithms, [761] and [447] released their open-source codes for the deepwater Green function, and [458] released an open-source code for the finite-depth Green function.…”