I asked this awhile back, when trying to do Drawing venn diagrams Gtk2 or Zinc does it far better, because they support transparecy levels in the colors. As far as the Tk Canvas goes 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = MainWindow->new();

# first create a canvas widget
my $canvas = $mw->Canvas(width => 300, height => 200)->pack();


my $one = $canvas->createOval(55, 20, 200, 190, 
                      -fill => 'blue',
              -outline=>'blue',
              -tags => ['blue'],
              -stipple => 'gray75',
              );

my $two = $canvas->createOval(105, 20, 250, 190, 
                      -fill => 'red',
              -outline=>'red',
              -tags => ['red'],
                      -stipple => 'gray12',
              #-stipple => 'transparent',  
                    );


my $ebutton = $mw->Button(-text => 'Exit',
                  -command => 'Tk::exit')->pack();


$canvas->Tk::bind("<Motion>", [ \&print_xy, Ev('x'), Ev('y') ]);

MainLoop();

sub print_xy {
  my ($canv, $x, $y) = @_;
#  print "(x,y) = ", $canv->canvasx($x), ", ", $canv->canvasy($y), "\n
+";
#my $x1 = $x+1;
#my $y1 = $y+1;

my (@current) = $canvas->find('overlapping', $x, $y, $x, $y);

foreach my $id(@current){ 
    print $canvas->gettags($id),' ';
}

print "\n";

}
__END__

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I'm not really a human, but I play one on earth. flash japh

In reply to Re: Tk::Canvas and using stipples by zentara
in thread Tk::Canvas and using stipples by BrowserUk

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