function main( x, y, p )

  local w = bs_width() / 2
  if w < 0.25 then
    w = 0.25
  end

  local updateDist = w / 2
  if w > 5 then
    updateDist = w/4
  end
  if w > 20 then
    updateDist = w/10
  end
  if w > 100 then
    updateDist = w/14
  end

  if not firstDraw then
    local distance = bs_distance( lastDrawX - x, lastDrawY - y )
    if distance < updateDist then
      return 0
    end
  end

  local r,g,b = bs_fore()

  local dx,dy = bs_dir()
  local vx,vy = bs_rotate( dx, dy, 3.14159/2 )

  local a = 255 * p * bs_opaque()

  local r1 = w*sr0
  local vx1 = vx * w * (0.5 - math.random()) / 3
  local vy1 = vy * w * (0.5 - math.random()) / 3
  bs_ellipse( x + vx1, y + vy1, r1, r1, 0, r,g,b,a )

  local r2 = w*sr1
  local vx2 = vx * w * (0.5 - math.random()) / 3
  local vy2 = vy * w * (0.5 - math.random()) / 3
  bs_ellipse( x + vx2, y + vy2, r2, r2, 0, r,g,b,a )

  lastDrawX = x
  lastDrawY = y
  firstDraw = false

  return 1
end

bs_setmode( 1 )
lastDrawX = 0
lastDrawY = 0
firstDraw = true

math.randomseed( bs_ms() )
sr0 = 1.0 + 0.2*math.random() - 0.1
sr1 = 1.0 + 0.2*math.random() - 0.1