documentclass{standalone}
  usepackage{pgf}
begin{document}
    begin{pgfpicture}
      pgfpathmoveto{pgfpoint{-1cm}{-1cm}}
      pgfpathlineto{pgfpointorigin}
      pgfnode{rectangle}{center}{Hello world}{}{pgfusepath{stroke}}
      pgfpathlineto{pgfpoint{1cm}{1cm}}
      pgfusepath{stroke}
    end{pgfpicture}
end{document}