_window =  1

_width  = 81
_height =  5

window _window, @"FutureBasic Cantor Set", ( 0, 0, 695, 100 )
WindowSetBackgroundColor( _window, fn ColorWhite )
text @"Menlo", 14.0, fn ColorRed

begin globals
CFStringRef gInterval( _height, _width )
end globals

local fn Init
  NSInteger i, j

  for i = 0 to _height - 1
    for j = 0 to _width - 1
      gInterval( i, j ) = @"◼︎"
    next
  next
end fn

local fn CantorSet( start as NSInteger, length as NSInteger, index as NSInteger )
  NSInteger i, j, segment = length / 3

  if segment == 0 then exit fn
  for i = index to _height - 1
    for j = start + segment to start + segment * 2 - 1
      gInterval( i, j ) = @" "
    next
  next
  fn CantorSet( start, segment, index + 1 )
  fn CantorSet( start + segment * 2, segment, index + 1 )
end fn

NSInteger i, j

fn Init
fn CantorSet ( 0, _width, 1 )
for i = 0 to _height - 1
  for j = 0 to _width - 1
    print gInterval( i, j );
  next
  print
next

HandleEvents