I can't really help in any event, but can you clarify - "visible" as in "a different colour than the background" or "visible" as in "on screen"?

map{$a=1-$_/10;map{$d=$a;$e=$b=$_/20-2;map{($d,$e)=(2*$d*$e+$a,$e**2
-$d**2+$b);$c=$d**2+$e**2>4?$d=8:_}1..50;print$c}0..59;print$/}0..20

[download]
Tom Melly, pm@tomandlu.co.uk

In reply to Re: Tk::Text. How to find out if char is visible? by Melly
in thread Tk::Text. How to find out if char is visible? by artemave

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