From kde-devel  Wed May 19 18:21:44 1999
From: Geert Jansen <g.t.jansen () stud ! tue ! nl>
Date: Wed, 19 May 1999 18:21:44 +0000
To: kde-devel
Subject: Re: kbgndwm's future
X-MARC-Message: https://marc.info/?l=kde-devel&m=92722831909224

Antonio Larrosa wrote:

> Hi,
> 
> I would like to implement transparent backgrounds in konsole before I start
> exams, but I'm not completely sure if kbgndwm will stay as it is for much
> long (due to kdesktop talking and all that).
 
Hi,

I brought this up some time ago. The outcome of the discussion was that
(pseudo) transparent widgets is possible in the following ways:

1) kbgndwm exports the background as a pixmap (either to a file or in shared
memory) and programs use QWidget::setBackgroundPixmap().

2) True transparency: QWidget::setMask(). This only offers 100%
transparency, no alpha blending etc. It is also very slow if the
transparency mask is complex (i.e. text in konsole).

3) The only good way: write a X extension to support alpha channel
transparency.

From your post I see that you want to render the background yourself. Maybe
1) is a better alternative for that.

I implemented 1) as a proof of concept. You can still find my patch at
http://www.stack.nl/~geertj/kde/.

Greetings,
--
    Geert Jansen                       email: <g.t.jansen at stud.tue.nl>
    Phylosopher, Physicist                        PGP key ID: 0xD2B5E7CE