On Thu, 18 Jul 2002, Preetham wrote:
> > Be careful. A "Display" in X-Window terminology is a connection to
> > the X-server. A single client can open many "Display" connections all
> > to the same screen. It's a "screen" that indicates a framebuffer.
> Correct me if i am wrong:
You are wrong.
> 1.What you mean to say is:
> Display is a connection to a screen, and all clients that share the display,
> write graphics
> information to the same screen.
A "Display" in Xlib is a connection to a server. A Display is
exclusive to a client. A client can use that Display to render to
any Screen on the X-Server. A "Display" is an opaque handle within
the client's namespace. Actually, my comment about a single client
opening many Display connections was inaccurate. What I meant to
say was that a process may open as many Display connections as it
wants. Each Display connection is essentially a different client
and the X-server has no way of knowing that two particular clients
are really the same process. Basically, client == Display connection.
An app that opens a Display and uses a toolkit that also opens a
display is actually two clients. The X-server does not know that
they are the same application.
> 2. So, each X-Server can have only one framebuffer.
Each X-server can have as many framebuffers (screens) as it wants.
The #define limit in XFree86 is 32, but only 16 have been tested.
There is one special case (Xinerama) where multiple framebuffers are
used to make up one screen from the client's point of view.
> 3.If i create a seperate buffer(one for each client, not a consolidated
> screen),
> is it possible to modify the XServer to capture the graphics generated by
> each
> of the clients and write them into their corresponding buffers.
I don't understand what you have described there. There is
only one framebuffer per screen. The concept of a separate buffer
per client doesn't make sense. While particular operations are
associated with a client some are not. Painting of a window background
for instance may be instigated by movement of another window without
any action initiating it by the client who created painted window. Also,
a client can render into a window it didn't create. Any drawable,
regardless of who created it is fair game for any client. And the
root window isn't owned by any client - it is owned by the X-server.
Perhaps if you would explain what it is that you are trying to
do.
Mark.
_______________________________________________
Xpert mailing list
[EMAIL PROTECTED]
http://XFree86.Org/mailman/listinfo/xpert
