>>>> See https://github.com/nilqed/latex2sixel 
-- in progess ...
-- Output thumbnails of )read test_draw
-- in folder src/
https://nilqed.github.io/drawfe/
For a black background add to ~/.gnuplot :
set term sixel
# change a color of border.
set border lw 1 lc rgb "yellow"
set linetype 8 lc rgb "white"
set linetype cycle 8
# change text colors of  tics
set xtics textcolor rgb "white"
set ytics textcolor rgb "white"
# change text colors of labels
set xlabel "X" textcolor rgb "white"
set ylabel "Y" textcolor rgb "white"
# change a text color of key
set key textcolor rgb "white"