[pdftex] hiding optional content

[Pawel Jackowski]

Hi,

> I've been experimenting with optional content groups (OCGs), putting
> them on top of each other with only one being visible at a time (which
> one can be chosen by the user). Now, a PDF viewer that does not support
> PDF 1.5 will display all layers at the same time. What I would like to
> find is a way to make the optional content -- well... optional. Is there
> any trick to hide the OCGs from older viewers?

afaik only Acrobat 6 and hi supports displaying PDF 1.5 optional 
content. Meybe you can fake macros supporting layers to so called marker 
content

	/Subpage BMC ... EMC

stuff? Similar in syntax, doesn't affect the preview, introduced in PDF 
1.3 I think... Be aware, that if the document is to be printed, many 
RIPs doesn't understand marked content and may simply ignore (not 
flatten!) it.

Regards,
-- 
Pawe/l Jackowski
P.Jackowski at gust.org.pl