\input fig4tex.tex
%
% 1. Definition of characteristic points
\figinit{pt}
\figpt 0:(0,0)
%
% 3. Writing text on the figure
\def\GraphFi{Triangle.PDF}
\figvisu{\figBoxA}{Demo {\tt \char`\\ figinsertE}}
{
% Insertion of the external file
\figinsertE{\GraphFi}
% Mark position of the origin
\figset write(mark=+)
\figwritew 0:$O$(5)
}
\centerline{\box\figBoxA}
\bye