You can do that with Gtk2 (Gnome2::Canvas and Goo::Canvas) with it's pango markup; but with Tk you would have to string together a few createText, use the bbox on the text to properly position everthing. You must also consider the anchor. Here is an example, but I hard coded 9 into the position, you probably can figure out a way to compute it( maybe not :-) ) 
#!/usr/bin/perl
use Tk;
use strict;

my $mw=tkinit;

$mw->fontCreate('big',
   -family=>'arial',
  -weight=>'bold',
  -size=>int(-24*24/14));


my $c = $mw->Canvas(-bg => 'white')->pack;

my $x = 0; my $y = 50;

my $t1 = $c->createText($x+50,$y,
           -anchor=>'w',
       -fill => 'red',
       -font => 'big',
       -text => '4',
          );
      
my ($bx,$by,$bx1,$by1)= $c->bbox($t1);
print "$bx  $by $bx1 $by1\n"; 

my $t2 = $c->createText ($bx1,$y+9,  #computing 9 is difficult
              -anchor=>'w',
             # -font => 'big',
              -fill => 'black',
              -text=> '2');

($bx,$by,$bx1,$by1)= $c->bbox($t2);
print "$bx  $by $bx1 $by1\n"; 
 
MainLoop;

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I'm not really a human, but I play one on earth CandyGram for Mongo

In reply to Re: Changing the Font of a specific character in a Text in a Canvas by zentara
in thread Changing the Font of a specific character in a Text in a Canvas by renegadex

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