If you want to scroll to datapoints, a Scrolled Tk::Canvas or a Gnome2::Canvas will let you scroll to a huge number with very little slowdown. The bigger the number, the more sensitive the scroll, but you can probably find a way to work around it. Like auto-scrolling to the next datapoint. I havn't tested the upper limit on this. :-)

#!/usr/bin/perl
use warnings;
use strict;

use Tk;

my $mw = new MainWindow;

my $c = $mw->Scrolled(
   'Canvas',
   -width        => 600,
   -height       => 400,
   -scrollregion => [ 0, 0, 8000000, 500 ],
   -scrollbars   => 'osoe'
 )->pack(
   -fill   => 'both',
   -expand => 1
 );

$c->createLine( 40, 40, 7500000, 40 ,
          -width => 5,
          -fill => 'red',

);

my $fixed = $c->createText( 0, 0, -anchor => 'nw', -text => 'Top of vi
+ew' );

MainLoop;
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