This takes me back to my FORTRAN days in the late 1960s when line printer code similar to this was the only option for plotting.
Try this:
spc = uint16(' ');
ast = uint16('*');
tringl = char(ones(6,6,'uint8')*32);
for k1 = 2:size(tringl,1)
tringl(k1,[8-k1,4+k1]) = ast;
end
for k1 = 1:size(tringl,1)
fprintf(1, '%s\n', tringl(k1,:))
end
Experiment to get the result you want.
