You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spm_swarp.m
    path of file: ./repos/bspm/thirdparty/spm8
    
    the code of the file until where you have to start completion: function that = spm_swarp(this,def,M)
% Warp surface.
% FORMAT that = spm_swarp(this,def)
% this - a gifti object
% def  - a deformation (nifti object or filename)
% that - the warped gifti object
%
% FORMAT that = spm_swarp(this,def,M)
% this - a gifti object
% def  - a deformation field (nx*ny*nz*1*3)
% M    - mapping from voxels to world, for deformation field
% that - the warped gifti object
%
%__________________________________________________________________________
% Copyright (C) 2009 Wellcome Trust Centre for Neuroimaging


    
function that = spm_swarp(this,def,M)
% Warp surface.
% FORMAT that = spm_swarp(this,def)
% this - a gifti object
% def  - a deformation (nifti object or filename)
% that - the warped gifti object
%
% FORMAT that = spm_swarp(this,def,M)
% this - a gifti object
% def  - a deformation field (nx*ny*nz*1*3)
% M    - mapping from voxels to world, for deformation field
% that - the warped gifti object
%
%__________________________________________________________________________
% Copyright (C) 2009 Wellcome Trust Centre for Neuroimaging

% John Ashburner
% $Id: spm_swarp.m 2859 2009-03-11 16:52:19Z guillaume $

if ~isa(this,'gifti'), this = gifti(this); end