Membuat Use Case Diagram di LaTeX

\documentclass{article}

\usepackage{tikz}

\usetikzlibrary{shapes, arrows}

\begin{document}

\tikzstyle{actor} = [rectangle, draw, text centered, minimum height=1cm, text width=3cm]

\tikzstyle{usecase} = [ellipse, draw, text centered, minimum height=2em]

\begin{tikzpicture}[node distance=2.5cm]

\node (user) [actor] {User};

\node (usecase1) [usecase, below of=user] {Use Case 1};

\node (usecase2) [usecase, right of=usecase1, xshift=3cm] {Use Case 2};

\draw [->] (user) -- (usecase1);

\draw [->] (user) -- (usecase2);

\end{tikzpicture}

\end{document}

--------------------------------------------------

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes, arrows}
\begin{document}
\tikzstyle{actor} = [rectangle, draw, text centered, minimum height=1cm, text width=3cm]
\tikzstyle{usecase} = [ellipse, draw, text centered, minimum height=2em]

\begin{tikzpicture}[node distance=2.5cm]
\node (user) [actor] {User};
\node (usecase1) [usecase, below of=user] {Use Case 1};
\node (usecase2) [usecase, right of=usecase1, xshift=3cm] {Use Case 2};
\draw [->] (user) -- (usecase1);
\draw [->] (user) -- (usecase2);
\node (system) [usecase, below of=usecase1, yshift=-2cm] {System};
\draw [->] (usecase1) -- (system);
\draw [->] (usecase2) -- (system);

\end{tikz picture}

\end{document}

--------------------------------------------------

\documentclass{article}

\usepackage{tikz}

\usetikzlibrary{shapes, arrows}

\begin{document}

\tikzstyle{actor} = [rectangle, draw, text centered, minimum height=1cm, text width=3cm]

\tikzstyle{usecase} = [ellipse, draw, text centered, minimum height=2em]

\begin{tikz picture}[node distance=2.5cm]

   \node (user) [actor] {User};

   \node (usecase1) [usecase, below of=user, yshift=-2cm] {Use Case 1};

   \node (usecase2) [usecase, right of=usecase1, xshift=3cm] {Use Case 2};

   \draw [->] (user) -- (usecase1);

   \draw [->] (user) -- (usecase2);

   \node (system) [usecase, below of=usecase1, yshift=-2cm] {System};

   \draw [->] (usecase1) -- (system);

   \draw [->] (usecase2) -- (system);

   \node (database) [rectangle, below of=system, yshift=-2cm] {Database};

   \draw [->] (system) -- (database);

\end{tikz picture}

\end{document}