Fltk toolkit: how to force *non*-anti-aliased operation

[h6mgos8bn6fb]

Hello!

Octave version 4.0.3 (Debian Stretch; sorry, didn't check latest version).

I do not want modern and beautiful anti-aliasing (AA). How to force all 
graphics to be non-anti-aliased?

Text can be made non-AA *in gnuplot* using:
set(0,'defaultaxesfontname','terminus');
set(0,'defaultaxesfontsize',12);
set(0,'defaulttextfontname','terminus');
set(0,'defaulttextfontsize',12);
plot(1:N);
title(['wfevew']);

But when I do it in fltk, I get garbage (tried several sizes, that do work for 
gnuplot):
http://img12.lostpic.net/2018/02/10/f059025c75419074cb77ebe4cce4c6e7.png

Also, the blue line is AA-ed.

Gnuplot works fine -- fully non-AA-ed: text and the blue plot line:
http://img12.lostpic.net/2018/02/10/019157999eb528d14b99c42b11b2b4dc.png

Thanks.