Suppress replotting of plot3d, param3d

[Frank Hrebabetzky]

When I call plot3d, param3d or the like more than once (same window), 
the plot is redrawn each time and the viewpoint is lost, that is only 
the last viewpoint becomes effective. Is there a way to suppress this 
replotting? Kind of generating surfaces and lines with some graphics 
primitives and plot everything with just one command?

Thanks,
-- 
Frank Hrebabetzky	Tel. (48) 3239 2258
Photonita Ltda.		http://www.photonita.com.br
Brazil