A simple efficient way to scroll alot of text, like for a teleprompter. It scrolls fast for demo, just slow it down. It also only handles plain text, trying to display html or code, will interfere with the markup process.
#!/usr/bin/perl
use warnings;
use strict;
use Gtk2 '-init';
use Gnome2::Canvas;
use constant TRUE=>1;
use constant FALSE=>0;
my $ts ;
if($ARGV[0]){
open (FH,"< $ARGV[0]");
read( FH, $ts, -s FH );
close FH;
}else{
while(<DATA>){ $ts .= $_ }
}
$ts =~ tr[\x0a\x0d][ ]d; #strip newlines
my $width = 650;
my $height = 60;
my $window = Gtk2::Window->new();
my $canvas = Gnome2::Canvas->new_aa();
my $black = Gtk2::Gdk::Color->new (0x0000,0x0000,0x0000);
$canvas->modify_bg('normal',$black);
$window->add($canvas);
$window->signal_connect('destroy'=>\&_closeapp);
$window->set_default_size($width,$height);
my $root = $canvas->root;
my $markup = "<span foreground= '#00FF00' size='50000'
weight = 'ultralight'><i><u> $ts </u></i></span>";
my $text = Gnome2::Canvas::Item->new($root, 'Gnome2::Canvas::Text',
#text => $markup,
markup => $markup,
fill_color => 'green',
anchor => 'w',
justification => 'left',
x=>0,
x_offset=> -$width/3,
y=>30);
$text->raise_to_top();
$window->show_all();
my $timer = Glib::Timeout->add(1000/24, \&timer);
my ($x1, $y1, $x2, $y2) = $text->get_bounds;
print "$x2\n";
my $right_bound = $x2 + $width;
Gtk2->main();
sub timer {
$text->move( -20, 0 );
my ($x1, $y1, $x2, $y2) = $text->get_bounds;
print "$x2\n";
if($x2 < -40){
$text->move( $right_bound + 60, 0 );
}
return 1;
}
sub _closeapp{
Gtk2->main_quit();
return 0;
}
__DATA__
This article is Copyright 1990-2004 by Steve Summit. Content from the
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+e
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