\documentclass{article}
\usepackage[usenames]{color}
\usepackage{gastex}

\begin{document}

% Nodes, colors, etc...

\begin{center}
\begin{picture}(105,70)(-15,-65)
\put(-15,-65){\framebox(105,70){}}
  \node[Nmarks=if](A)(0,0){1}
  \node[Nw=15,Nh=6,Nmr=0](A)(25,0){rectangle}
  \node[Nw=12,Nh=6,Nmr=3](A)(50,0){oval}

  \node(B)(0,-15){Nadjust=n}
  \node[Nadjust=w,Nmr=2](B)(25,-15){Nadjust=w}
  \node[Nadjust=wh,Nmr=1](B)(50,-15){Nadjust=wh}
 
  \gasset{Nadjust=w,Nadjustdist=3}
  \node[Nmarks=i,iangle=210,ilength=5](C)(0,-30){imark}
  \imark[iangle=150,ilength=10,linecolor=Red](C)
  \node[Nmarks=f,fangle=30,flength=5,linecolor=Green](C)(25,-30){fmark}
  \fmark[fangle=-30,flength=10,linecolor=Blue](C)
  \node(C)(50,-30){rmark}
  \rmark[linecolor=Red](C)\rmark[rdist=1.4,linecolor=Green](C)
  \node[Nmarks=ifr](C)(75,-30){all}

  \node(D)(0,-45){framed}
  \node[Nframe=n,fillcolor=Yellow](D)(25,-45){filled}
  \node[fillcolor=Yellow](D)(50,-45){both}
  \node[fillcolor=Yellow,
        linecolor=Green](D)(75,-45){\textcolor{RedViolet}{RedViolet}}

  \node[linewidth=0.5](E)(0,-60){Thick}
  \node[linewidth=1,linegray=0.8](E)(25,-60){Gray}
  \node[dash={1.5}0](E)(50,-60){Dash}
  \node[dash={4 1 1 1}0,linecolor=Red](E)(75,-60){More dash}
\end{picture}
\end{center}

\end{document}