nanogui: Current plans for Microwindows
Subject:
Re: [nanogui] Current plans for Microwindows
From:
Alex Holden ####@####.####
Date:
15 Jul 2002 17:24:56 -0000
Message-Id: <3D330263.8010200@linuxhacker.org>
Keith Williams wrote:
> 3) One of the items that really caught my eye with your package was the
> semi-transparent windows. This was something that we were hoping to
> implement to overlay dimmed-out controls over a plot window. I've seen a
> couple of posts that suggested that that option was not ready for prime
> time. Was this a mis-understanding on my part? If not, when would you
> expect that the issues with that feature to be resolved?
The way that transparent windows are implemented in Nano-X is basically
not terribly useful. All it does is not draw the background of the
window when you turn the "transparent" flag on. If you move the window,
or the contents of a window underneath it changes, the background will
not be updated.
I have implemented both shaped window support (see the nxeyes and tux
programs) and alpha channel support (see the nbreaker game) in my CVS
tree which you can get from here:
http://www.linuxhacker.org/pub/cvs-snapshots/microwin-aph/
I think it's unlikely that true translucent window background support
(the kind of thing Mac OS X is capable of) will be implemented any time
soon, if ever, in Nano-X as it is a complex problem to solve and tends
to require a lot of memory and processor power (and ideally accelerated
video hardware support). Keith Packard wrote a useful article about the
problem with regards to X, which applies just as well to Nano-X:
http://www.xfree86.org/~keithp/talks/KeithPackardAls2000/index.html
You can do what you want using the alpha channel support by blending the
controls directly onto the plot window using a per-control alpha
channel. The nbreaker game does this (note how all the sprites in the
game have translucent areas through which you can see the window
background graphics).
--
------------ Alex Holden - http://www.linuxhacker.org ------------
If it doesn't work, you're not hitting it with a big enough hammer
