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#!/usr/local/bin/perl -w

use Tk;

use Tk::Xlib;

$top = MainWindow->new();

# Check out some of Xlib stuff
$screen = $top->Screen;
$sw     = $screen->WidthOfScreen;
$sh     = $screen->HeightOfScreen;
$name   = $top->Display->DisplayString;
print "$name is [$sw,$sh] pixels\n";

sub DoKey
{my $w = shift;
 my $e = $w->XEvent;
 my $msg = "key : " . $e->A;
 my $dpy = $w->Display;
 my $id  = $w->WindowId;
 unless (defined $w->{GC})
  {
   $w->{GC} = GC->new($dpy,$id,
                     Foreground => 5,
                     Font => $dpy->XLoadFont("-*-Courier-Medium-R-Normal--*-240-*-*-*-*-*-*"));
  }
 my $gc  = $w->{GC};
 $dpy->XDrawString($id,$gc,$e->x,$e->y,$msg);
}

$top->bind("<Any-KeyPress>",\&DoKey);

$top->bind('<ButtonPress-1>',[\&DrawLine,1]);
$top->bind('<ButtonRelease-1>',[\&DrawLine,0]);
$top->bind('<B1-Motion>',[\&DrawLine,1]);

$top->bind('<ButtonPress-2>',[\&DrawWin,1]);
$top->bind('<ButtonRelease-2>',[\&DrawWin,0]);
$top->bind('<B2-Motion>',[\&DrawWin,1]);

sub DrawLine
{
 my $w = shift;
 my $draw = shift;
 $w->tmpLine(@{delete $w->{'tmpLine'}},6) if (exists $w->{'tmpLine'});
 if ($draw)
  {
   my $e  = $w->XEvent;
   my $x  = $e->x;
   my $y1 = 0;
   my $y2 = $y1 + $w->Height;
   $w->{'tmpLine'} = [$x,$y1,$x,$y2];
   $w->tmpLine(@{$w->{'tmpLine'}},7);
  }
}

sub DrawWin
{
 my $w = shift;
 my $draw = shift;
 my $l = delete $w->{'tmpWin'};
 if ($draw)
  {
   my $e = $w->XEvent;
   unless (defined $l)
    {
     $l = $w->Toplevel(-background => 'black');
     $l->overrideredirect(1);
    }
   $l->MoveResizeWindow($e->X, $w->rooty, 1, $w->Height);
   $w->{'tmpWin'} = $l;
  }
 else
  {
   if (defined $l)
    {
     $l->destroy;
    }
  }
}


MainLoop();