[pdftex] Problem with colors in included PDF file

[Andreas Matthias]

Reinhard Kotucha wrote:

>>>>>> "Andreas" == Andreas Matthias <amat at kabsi.at> writes:
> 
>     > [...]  Default should be `black', which is what most people 
>     > expect. 
> 
> A few points should be considered:
> 
> The "defaultcolor" option is an optional argument of
> \includegraphics, isn't it?

Yes.

 
> I even do not think that defaultcolor=black is what everybody expects.
> Well, if people use TeX to write books, it is certainly the case.
> Most people do that and thus you are right with this assumption.

I think an included PDF should look the same like the original
PDF. If it does not, it will always be confusing.

>From PDF Ref:

  p.147 (4.3 Graphics State): The graphics state is initialized
  at the beginning of each page, using the default values specified
  in Tables 4.2 and 4.3.

  Table 4.2:
   color    ... Initial value: black


So if a page does not specify any color, it will default to black.
And that's what all PDF viewers do. Is there any reason, why this
behavior should change, if the PDF is included by pdftex? I think
black is the only correct default color.

Nevertheless, it is a very nice feature, if graphics, which have no
color defined and therefore would default to black (if viewed solely
in a PDF viewer), can adjust their color (after inclusion) to the 
current text color or any other color. But this should not be the
default.

If PDFs are black in a PDF viewer they should be black after
inclusion by default. Everything else should be a feature but
not the default behavior.

Just as a reminder: The defaultcolor option would not change any
color explicitly specified in a PDF. It would just affect those
objects which have no explicit color and therefore are displayed
in black by a PDF viewer.

Ciao
Andreas