Re: control-center 2.13.90 released

[Federico Mena Quintero <federico ximian com>]

On Wed, 2006-02-01 at 16:04 +1300, Glynn Foster wrote:

> Changing backgrounds quickly doesn't really help, since
> XSetWindowBackgroundPixmap() isn't being called each time, at least when
> nautilus has been disabled [I'm only checking that case right now] - or
> that's what I'm seeing while using DTrace.

What does "each time" represent here?  Each time you select a different
wallpaper, or change an option (gradient/color/etc)?

> Also, the default set of backgrounds have completely different sizes and
> types as a quick browse through /usr/share/pixmaps/backgrounds will
> show. It might be cunning to pick one relatively plain background,
> duplicate it a couple of times and change the colour of it, then edit
> the xml files in /usr/share/gnome-background-properties for different
> wallpaper options.

Let's use the real-world data we have, that is, the real stuff
in /usr/share/pixmaps/backgrounds.

I'm interested in knowing

- how long do we take to load the image from disk and decode it.  For a
1400x1050 JPEG, this takes 0.27 seconds for me from looking at strace.

- how long do we take to generate the pixmap we set on the root window,
based on the decoded pixbuf.  No idea how long that takes.  Test the
various cases:  this is the cross product of { solid image, image with
alpha} x { solid color, gradient } x { tiled/untiled image covers the
background completely, background shows through }.  libbackground has
some fancy code to detect the various coverage conditions; ensure that
that code is working correctly.

- how long does nautilus take to pick up the pixmap and repaint its
desktop window.  That takes about 1 second for me, due to XRENDER bugs.

  Federico