I imagine its possible but I haven't a clue to know even where to beg in looking. Is it possible to write to the root window in X (i386 Linux)? I'd like to manipulate some images and write them there.

THX - Jon

i think i came across something in the past probably for KDE3.5. might me desktop specific.

looking at kde/gnome/freedesktop API might be helpfull

- V
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Jon Foster wrote

I imagine its possible but I haven't a clue to know even where to beg in looking. Is it possible to write to the root window in X (i386 Linux)? I'd like to manipulate some images and write them there.

No idea how to do it via LCL, but here is a small sample of code I use for a fpGUI utility application which draws a rectangular outline around components/windows (of any X11 application) under the mouse pointer.

The trick is to draw to the DefaultRootWindow(display) result of whatever display you are working with.

-------------------------

procedure TMainForm.DrawOutline;
begin
  if not FOutlineDrawn then
  begin
    XSync(fpgApplication.Display, False);
    XDrawRectangle(
        fpgApplication.Display,
        DefaultRootWindow(fpgApplication.Display),
        FOutlineGC,
        newrect.Left, newrect.Top, newrect.Width, newrect.Height);
    lastrect := newrect;
    FOutlineDrawn := True;
    lblPos.Text := Format('(%d,%d)', [newrect.Left, newRect.Top]);
    lblSize.Text := Format('(%d,%d)', [newrect.Width, newRect.Height]);
    lblHandle.Text := IntToHex(last_child, 6);
  end;
end;
-------------------------

Jon Foster wrote

I imagine its possible but I haven't a clue to know even where to beg in looking. Is it possible to write to the root window in X (i386 Linux)? I'd like to manipulate some images and write them there.

I can't remember if writing is supported, but   DC := GetDC(0);
will give you a root device context.

Marc

Thanks! I'll have to give it a shot when I get a chance.

-Jon