[pdftex] redundant objects with includegraphics

[Han The Thanh]

> With this changed semantics, "\pdfembed" is then trivial: It just
> embeds all the pages and resources at once, and adds entries to the
> figure table for each page.  Future attempts to load individual pages
> from "a.pdf" using \pdfximage will simply reference the already
> embedded pages.

if I do it, I would try to keep track of all copied objects from pdf
images. Each pdf image would have a list of all objects that have been
copied from the image. Images that have the same file name would share
their object list. When an object is being copied, its number is checked
whether it has been copied yet to avoid duplicates. This way only needed
objects are copied and just once. The penalty might be in the running time,
but I really doubt it matters. The rest like syntax & use with
\includegraphics remains tha same.

Thanh