How can I smooth 'trisurf' surface-plot?

How can I smooth the surface generated by 'trisurf' command?

To create a surface from some scattered data, I use the method suggested here:

% initially, x, y, z are coordinates of scattered data
x = scatteredValuesX;
y = scatteredValuesY;
z = scatteredValuesZ;

% to create a surface from the scattered data, a triangulation is used
% this method is suggested here: https://au.mathworks.com/matlabcentral/fileexchange/5105-making-surface-plots-from-scatter-data
tri = delaunay(x,y);
trisurf(tri, x, y, z);

The result is very noisy and I would like to smooth the surface, but I have not yet discovered the way of how to achieve this goal.

I have found a function 'smoothn' here which could potentially achieve what I need, but I am not sure if it is possible to adapt my data in order to feed this function properly.

Any input would be appreciated.