No one mentioned the use of splinesteps, but here is how to smooth your curves. 
#!/usr/bin/perl
use warnings;
use strict;
use Tk;

my $mw = tkinit;
$mw->geometry("600x400+100+100");
my $canvas = $mw->Canvas(-width => 600, -height => 400,
                         -bg => 'black')->pack();


my $line5 = $canvas->createLine(400,0,500,150, 
                          -fill => 'pink',
                          -width => 5,
              );


my $line6 = $canvas->createLine(0,200,100,350,0,300,350,200, 
                          -width => 5,
                          -smooth => 1,
              -fill => 'lightgreen');


my $line7 = $canvas->createLine(300,200,500,350,0,300,350,200, 
                          -width => 5,
                          -smooth => 1,
              -splinesteps => 20,
              -fill => 'purple');


MainLoop;

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

In reply to Re: How to draw a curved arrow in perl Tk canvas ? by zentara
in thread How to draw a curved arrow in perl Tk canvas ? by KuntalBhusan

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