( fFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfFfF )

: sinefield ( -- )
  numlines 0 do
    i
    screen-width 0 do
      dup 
      dup sin i sin +
      swap i pixeladr
      c!
    loop 
    drop 
  loop
;