With very little effort one can change the function DumpDisplay from the tutorial to a DumpDisplayToXPM, which will create a human-readable as well as computer readable file.

/* XPM */
static char *xpm_[] = {
"100 64 2 1",
"* c #000000",
". c #ffffff",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"....................................................................................................",
"......*.....*.......................****.........*..................*...*****.*.....................",
"......*.....*.......................*...*........*.................**...*.....*.....................",
"****..*.**..*.....*...*..***........*...*..***..***....***..........*...****..*.**..................",
"*...*.**..*.*.....*...*.....*.......****..*...*..*........*.........*.......*.**..*.................",
"****..*...*.*.....*...*..****.......*...*.*****..*.....****.........*.......*.*...*.................",
"*.....*...*.*.....*..**.*...*.......*...*.*......*..*.*...*.........*...*...*.*...*.................",
"*.....****..*****..**.*..****.......****...***....**...****........***...***..****..................",
"....................................................................................................",
};

Using PixelMator this can easily be translated to PNG:

Here’s the function:

function DumpDisplayToXPM()
  print("/* XPM */")
  print("static char *xpm_[] = {")
  print("\"100 64 2 1\",")
  print("\"* c #000000\",")
  print("\". c #ffffff\",")
  for y=0,63 do
    s = "" 
    for x=0,99 do
      if 0 ~= nxt.DisplayGetPixel(x,y) then
        s = s .. "*" 
       else
        s = s .. "." 
      end
    end
    print( "\"" .. s .. "\"," )
  end
  print("};")
end

Currently this function outputs to the console, which is fine for our purpose, so we can copy and paste it over to our computer.

As said earlier, I’m using MacVim which supports XPM natively.