[pdftex] possible metapost inclusion bug

[Klaus Guntermann]

Patrick Riley writes:
 > I have a bug involving the colors of multi-level metapost files, but I
 > don't know whose bug it is and I'm hoping someone can either help me
 > or tell me where the right place to go is.
 > 
 > Here's the setup. 
 > 
 > * I have a .fig file created with xfig version 3.2.3d. It contains some
 >   black circles.
 [...]
 > * When I look at the pdf file (before or after running PPower4 on the
 >   file), some of the circles are drawn in the test color of green
 >   instead of the black they are supposed to be.

This problem has been classified a feature in an earlier discussion,
although I do not recall where the discussion has been made.

In the process of creating the files to be included there is an
optimization which does not specify the color of any picture item, if
it is black and all previous items have been black, too.
This has the advantage that you can change the color of all items if
they are all black, just by changing the current color before you
include the picture. We have used this (and therefore classified this
as a feature) to include the same picture all black for a printed paper
version or in a different color to highlight it on a slide, using the
same picture representation.

If you have different colors in your picture it can be that some of
the black items will change colors and some are still black, if the
default color is different when the picture is included. This is what
you observed. To my knowledge there is no way to control which items
are "color sensitive" and which not, because it depends on the position
in an internal list of Xfig. This position may change during each
editing session and may lead to different results after changing a
picture.

If you want to make sure that all black elements come out in black you
have to switch to the color black before including the picture.

I hope this helps,
        Klaus
-- 
	Klaus Guntermann	<guntermann at iti.informatik.tu-darmstadt.de>
	FG Systemprogrammierung, FB Informatik, TU Darmstadt
	Wilhelminenstr. 7, 64283 Darmstadt, Germany