Generate map with custom border

Hello everyone,

I am trying to plot Cities on a random generated map (Travelling Salesman Problem) and I was wondering how to add a border in which I want cities to plot?

For example if I upload an image of a country, how to generate borders so the cities are inside that "country" ?

Here is the code for random map initialization:

C = get(handles.number_cities, 'String');

C = str2double(C);

if(isnan(C)), errordlg('Parameters must be numerical.','Mapping Error');

elseif(C <= 0), errordlg('Number of cities must be greater than zero','Mapping Error');

else

M = zeros(C,2); % Map initialization

for id_C = 1:1:C

M(id_C,1) = randi(100); % Random map

M(id_C,2) = randi(100);

end

end