Compiz and Fedora

[Stewart Adam]

What are the plans (if any) for compiz-fusion?

Stewart

On Mon, 2007-08-13 at 16:30 -0400, Kristian Høgsberg wrote:
> Hi,
> 
> I read through the entire "Enabling Compiz by default" thread and
> decided to send out a braindump/status/roadmap type of writeup, to
> explain what we're doing in this area and where we'd like to go:
> 
> 1) We are working towards being able to enable a compositor by default.
> 
>         Redirected direct rendering, Xv, Java problems, these are
>         problems in the drivers and X server and affects all
>         compositors.  To get this done, we need to land a big chunk of
>         code in the kernel (the DRM memory manager), we need to update
>         the X server, the 2D drivers and the 3D drivers to take
>         advantage of the new memory manager.  We need to fix Xv.
>         Hopefully the OpenGL support will broaden to support more
>         chipsets (nouveaou, avivo). Getting all this to a shippable
>         state may take years, and in the mean time, the composited
>         desktop, whether it's compiz, kwin4 or something else will only
>         be an opt-in tech demo.
>         
> 2) Once we get there, the default compositor will be compiz.
> 
>         Some people can't get over on the wobbly windows and spinning
>         cube, and claim it's over the top or apparently get nauseous.
>         At the core, compiz is just a very efficient OpenGL redraw loop
>         with a flexible plugin architecture.  Compiz allows burning
>         windows and spinning cubes, but we ship it in a very toned down
>         default configuration that looks a lot like good old metacity.
>         Consider xeyes; like wobbly windows, it's a neat tech demo and
>         shows off the flexibility of X, but just because nobody runs
>         xeyes for more that 2 minutes at a time that doesn't mean that X
>         (or shaped windows) isn't useful.
>         
>         A valid point about compiz is that it is not yet a great window
>         manager.  Metacity has a few years of head start there, but that
>         doesn't mean that we can't fix compiz or that it'll be
>         duplicated effort.  For now, our efforts have gone towards
>         fixing the big underlying shortcomings in the X and OpenGL
>         stack, which has left compiz with a set of minor (but certainly
>         annoying) windows manager bugs.
>         
>         Other spins (Fedora KDE or Fedora XFCE) can set up different
>         default compositing managers, and they will of course benefit
>         from the infrastructure work mentioned in 1).
> 
> 3) Metacity as a compositing manager.
> 
>         We tried it and decided that the metacity code base was not a
>         welcoming place for a compositor.  When we put down the work in
>         metacity, the conclusion was to leave this very stable and well
>         tested code base alone instead of injecting an OpenGL based
>         compositor.  The flip side of this decision is that we can now
>         do a clean break in compiz and assume throughout the code that
>         we're an OpenGL based combined compositing and window manager.
>         
> 4) Compiz configuration tools
> 
>         desktop-effects is close to what we should ship by default,
>         perhaps we want to fold it into the new
>         gnome-appearance-properties capplet as a new tab.  At the same
>         time, we want to allow installation of other compiz
>         configuration managers for people who like the tweak-ui kind-of
>         tools.
> 
> 4) Power consumption and other hand-wavey fud arguments.
> 
>         Clearly running a 3D screen saver at the full frame rate is
>         going to burn more battery than the blank screen saver, but
>         that's not really relevant here.  When idling, compiz and
>         metacity use exactly the same amount of power.  There are no
>         code paths anywhere in the stack that "turn on 3d powerplanes".
>         My bet is that it's more power consuming to wake up all
>         applications to redraw their exposed areas under the window
>         you're dragging than it is for compiz to just recomposite that
>         out of textures already in video memory.
>         
> 5) If you don't know what you're talking about, will being excessively
> dismissive and assertive make you right?
> 
>         No.
>         
> Kristian
> 
>