%method switcher/wrapper

function  [cropped_mesh, D] =apply_mask(mesh, center_ind, crop_size, D)
if (nargin<4)
% [cropped_mesh, D] =diffusion_mask(mesh, center_ind, crop_size);
 [cropped_mesh, D] =geodesic_mask(mesh, center_ind, crop_size);
else
% [cropped_mesh, D] =diffusion_mask(mesh, center_ind, crop_size, D);
[cropped_mesh, D] =geodesic_mask(mesh, center_ind, crop_size, D);
end