[pstricks] psRandom (PSTricks-add command) and Beamer overlays

[Christian Häger]

Hello,

consider the following minimal example, where the \psRandom command is used to draw random points on a slide, together with an overlay. 

\documentclass{beamer} 
\usepackage{pstricks-add} 

\begin{document}
\begin{frame}
	\begin{pspicture}(5,5)
		\psRandom[randomPoints=100](0,0)(5,5){\pscircle(2.5,2.5){2.5}}
	\end{pspicture}
	\uncover<2>{I am an overlay}
\end{frame}
\end{document}

The effect is that on the second slide, where the overlay appears, the random points are changing. I assume that this is because beamer automatically copies the \psRandom command on each overlay-slide and therefore draws new random points on every slide. Is there a possibility to have the same random points appear on every slide? I don't know how the \psRandom command works but maybe it uses some input seed for a random number generator which could be frozen for the slide? 

Thanks in Advance!
Christian