how to control contour label position ?

[vetoulis(at)aurelius.bu.edu (&Ggr;&igr;&ohacgr;&rgr;&ggr;&ogr;&sfgr; &Bgr;&egr;&tgr;&ogr;&uacgr;&lgr;&eegr;&sfgr;)]

Hi,

I am generating contour plots and I am using the "levels" and "c_annotation"
parameters. However because I need to superimpose other objects over the
contour plot, I need to move the labels from where IDL is placing them. 
A better description would be to "slide" them along the contour, to places
where they will not conflict with the other elements in the plot.

I am not asking for an automatic way, but I would imagine there might be
a variable that measures length along a contour. For that matter, how
does IDL decide where  to place each label on its contour?

Thanks for any help!

-- 
G. Vetoulis
Boston U.