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

\begin{document}

% New macros in gastex 2.1

\begin{center}
\begin{picture}(80,80)(-40,-40)
% \put(-40,-40){\framebox(80,80){}}
  \drawline(-40,0,40,0)
  \drawline(0,-40,0,40)
  \drawline[AHnb=0](-30,-30,30,30)
  \drawcbezier(-30,-20,-30,0,-10,0,-10,20)
  \drawcbezier[AHnb=0,dash={1.5}0](-30,20,-30,0,-10,0,-10,-20)
  \drawqbezier(1,-20,20,-20,20,-1)
  \drawqbezier[AHnb=0,linecolor=Green](1,-20,1,-1,20,-1)
  \drawcircle[Nfill=y,fillcolor=Yellow](10,30,10)
  \drawrect[Nfill=y,fillcolor=Yellow,dash={1.5}0](15,-35,35,-25)
  \drawoval(-20,30,20,10,3)
\end{picture}
\end{center}

\end{document}