Printing pages with objects with opacity != 1.0 gives bad results

[Stefan]

If you print a document which contains an object with opacity != 1.0
the WHOLE page is rendered (by cairo) as bitmap (to be more precise:
the objects which are behind the object). This reduces the
print quality significantly.

The reason is that for each object with opacity != 1.0 inkscape does
basically the following:

  cairo_push_group()
  paint object...
  cairo_pop_group_to_source()
  cairo_paint_with_alpha(opacity)

Since the source is the whole page and since opacity is != 1.0, cairo
has to fall back to a bitmap for the whole page for the postscript
backend.

As a remedy, you can replace the opacity of the object to 1.0 and adjust the
fill-opacity and stroke-opacity accordingly. Then only the object
itself is rendered as bitmap instead of the whole page. For example,
if the opacity is initially 0.5 and both the fill and stroke opacity
are 1.0, set the opacity to 1.0 and set both the fill and stroke
opacity to 0.5. Script for this procedure follows.

[Stefan (stefan-roellin)]

Example which illustrates the mentioned issue.

[Stefan (stefan-roellin)]

first part of script to replace opacity

[Stefan (stefan-roellin)]

second part of script to replace opacity

[jazzynico (jazzynico)]

Confirmed on Windows XP, Inkscape trunk revision 10948.

[jazzynico (jazzynico)]

Marking duplicate of Bug #524255 "Adding transparence kills fine printing and exporting". Don't hesitate to comment if you think this is a different issue.

[su_v (suv-lp)]

<off-topic>
Why linking the older report (with a detailed description of the underlying problem) as duplicate to a newer one?
</off-topic>

IMHO the underlying proplem is not limited to printing, but inherent to cairo-based EPS/PS exports in general.

[su_v (suv-lp)]

Nevermind my prior comment.

[jazzynico (jazzynico)]

~suv - The most recent report provides an example file, is more generic, and has a better title than the old one (IMHO).