function param1()
  return "interval", 10, 100, 50
end

function param2()
  return "color rnd", 0, 100, 50
end

function param3()
  return "length", 1, 100, 50
end

function main( x, y, p )

  local w = bs_width_max() * 0.25
  if w < 5 then
    w = 5
  end

  if not firstDraw then
    local distance = bs_distance( lastDrawX - x, lastDrawY - y )
    if distance < w * bs_param1()/20 then
      return 0
    end
  end

  local dx,dy = bs_dir()
  local nx,ny = bs_normal()

  local num = math.random( 0, 3 )
  local i
  for i = 0,num do
    local idx = bs_grand(0,0.8)*w
    local rnd = 0.5 + math.random()+bs_param3()/100
    local kai = 3.14/4*bs_grand(-0.2,0.5)

    bs_bezier_begin( 0, 0 )
    bs_bezier_c( 0.1, -0.4, 0.0, -0.8, -0.6, -1.2 )
    bs_bezier_c( 0.1, -0.9, 0.2, -0.4, 0, 0 )
    bs_bezier_mul( w*5, w*rnd*5 )
    bs_bezier_rotate( kai )
    bs_bezier_move(  x+idx/2, y+idx )

    local r,g,b = bs_forebg( 1.0 - math.random()*bs_param2()/100 )
    bs_fill( r,g,b, 255 )
  end

  local num = math.random( 0, 3 )
  local i
  for i = 0,num do
    local idx = bs_grand(0,1.2)*w
    local rnd = 0.2 + math.random()+bs_param3()/100
    local kai = 3.14/4*bs_grand(-0.2,0.5)

    bs_bezier_begin( 0, 0 )
    bs_bezier_c( -0.2, -0.7, -0.2, -1.3, 0.1, -2.0 )
    bs_bezier_c( -0.3, -1.2, -0.3, -0.6, 0, 0 )
    bs_bezier_mul( w*2, w*rnd*2 )
    bs_bezier_rotate( kai )
    bs_bezier_move(  x+idx*0.5, y+idx )

    local r,g,b = bs_forebg( 1.0 - math.random()*bs_param2()/100 )
    bs_fill( r,g,b, 255 )
  end

  lastDrawX = x
  lastDrawY = y
  firstDraw = false

  return 1
end

lastDrawX = 0
lastDrawY = 0
firstDraw = true