I don't believe X11 provides any means for Clients to ask the server for any information about any window
Sure it does. Ever used xmag? Or a graphics
editor like xpaint that allows you to pick
the colour of any pixel on the screen? xli or
xloadimage, that can inspect or share colour
palettes already in use (important in the time X-servers
often used 256 colour palettes)? fvwm2 has no
problem using partially transparent icons; and if I view
a partially transparent gif with display (which
comes with ImageMagick), I get to see what's underneath
(and even the focus goes to the underlaying application).
And you may be familiar with xscreensaver which
has a few screensavers that use the current display.
You can say a lot of bad things about X, that it's slow,
that it uses a lot of memory, that it's insecure, and that
it's hard to program with. But the one reason that it's
still going strong is that anything is possible. And that
includes transparency, and inspecting the pixels of other
applications. But I'm not an X-windows programmer (it's been
more than 10 years since I last wrote an X-windows program
(in C, pure, raw X-windows, no widget sets used)), so how
it's done, I do not know.
Abigail
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.
|