# Main data, globally available:
# Nun kapseln wir die Variablen in einer blessed Reference...
# $main ist eine Instanz der Klasse main
my $main = bless{
         resx           => 800,
         resy           => 600,
         border         => 30,
         fromx          => -4,
         tox            => 4,
         fromy          => -11,
         toy            => 11,
         xstep          => 200,
         function       => "- (x) ** 2 + 5",
         xzoomcenter    => 0,
         yzoomcenter    => 0,
         xtextspacing   => 8,
         ytextspacing   => 15,
         coordlinesteps => 5,
         coordfont      => "Arial 8 normal"
}, 'main';