nanogui: Transparent window with Nano-X
Subject:
Re: [nanogui] Transparent window with Nano-X
From:
"Greg Haerr" ####@####.####
Date:
8 Dec 2005 20:28:19 +0000
Message-Id: <08f601c5fc35$e59f3650$6401a8c0@gregnewport>
> Top Box (STB) where I want the transparency over the video plane. A STB
> generally contains three planes, namely - video plane, graphics plane
> and cursor plane. So I think if I run the 'malpha' demo program on a STB
> it will be displayed on Graphics plane. Now my question is that if I
> want to show the Video plane through the Graphics plane do I need to add
> some extra code to 'malpha' or the transparency of the Graphics plane
> over the Video plane is automatically handled by the Video/Graphics
> driver of STB ?
All hardware transparency will have to be specially handled
by your application code, by talking to the STB video/graphics
driver. Nano-X will only draw on the graphics plane, and
knows nothing about other hardware planes. When a window
receives an exposure message, then you'll likely want to
set parameters for the STB video plane.
Regards,
Greg
>
> Thanking you again.
>
> Regards,
> Aveek
>
> On Wed, 2005-12-07 at 10:01 -0800, Greg Haerr wrote:
> > > I want to create a transparent window using nano-X. What I'm trying to
> > > do is like that :
> > > There will be a window with some objects (geometrical figure) on top
of
> > > that. But the background of the window should be transparent, so that
> > > anything on desktop below the window could be seen. There is a demo
> > > program named 'malpha' within '/src/bin/' which deals with
transparency.
> > > But that doesn't serve my purpose because background is not
transparent
> > > here.
> >
> > The malpha demo shows that with external-to-server coding, it
> > is possible to simulate alpha blended surfaces with Microwindows.
> > This capability is not present in the server, however.
> >
> >
> > > Could anyone tell me whether this is really possible with Nano-X ? Or
> > > any idea about how to do this ?
> >
> > Well, it's certainly possible, but not without writing some tricky code
> > to add transparency handling to all windows and all refresh code.
> > I'd say its a pretty hard project. If you really want to do this,
> > make sure you completely understand how malpha.c works,
> > as well as all the code in nanox/srvutil.c.
> >
> > Regards,
> >
> > Greg
> >
> >
> >
>
>
