TikZ node with UML comment shape

Question

I'm wondering how could I draw node that looks like ** UML comment **. Any suggestions?

Answer 1

As it is stated in the tikz manual, there is no UML support in TikZ at the moment [p. 791]. So you might find MetaUML interesting, and especially their notes.

If you have installed MetaUML, simply save the following code as name.mp and type in the console mptopdf name.mp:

input metauml;
input TEX;

beginfig(5);
  Note.A("This class implements the formula:", 
          TEX("$\sum_1^n f(x)\cdot dx$"));
  drawObjects(A);
endfig;

end

You'll get this result as name.pdf.

So you have to define your UML structure externally and then just include the pdf in your document.

Have Fun!

Answer 2

\pgfdeclareshape{umlnote}
    {
        \inheritsavedanchors[from=rectangle]
        \inheritanchorborder[from=rectangle]
        \inheritanchor[from=rectangle]{center}
        \inheritanchor[from=rectangle]{north}
        \inheritanchor[from=rectangle]{north east}
        \inheritanchor[from=rectangle]{north west}
        \inheritanchor[from=rectangle]{south}
        \inheritanchor[from=rectangle]{south east}
        \inheritanchor[from=rectangle]{south west}
        \inheritanchor[from=rectangle]{west}
        \inheritanchor[from=rectangle]{east}
        \backgroundpath{
            \southwest \pgf@xa=\pgf@x \pgf@ya=\pgf@y
            \northeast \pgf@xb=\pgf@x \pgf@yb=\pgf@y
            \pgf@xc=\pgf@xb \advance\pgf@xc by-5pt
            \pgf@yc=\pgf@yb \advance\pgf@yc by-5pt
            \pgfpathmoveto{\pgfpoint{\pgf@xa}{\pgf@ya}}
            \pgfpathlineto{\pgfpoint{\pgf@xa}{\pgf@yb}}
            \pgfpathlineto{\pgfpoint{\pgf@xc}{\pgf@yb}}
            \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@yc}}
            \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@ya}}
            \pgfpathclose
            \pgfpathmoveto{\pgfpoint{\pgf@xc}{\pgf@yb}}
            \pgfpathlineto{\pgfpoint{\pgf@xc}{\pgf@yc}}
            \pgfpathlineto{\pgfpoint{\pgf@xb}{\pgf@yc}}
            \pgfpathlineto{\pgfpoint{\pgf@xc}{\pgf@yc}}
        }
    }

copied from documentation