DRAW_POINTS = 100
MIN = 20
MAX = 700
cx = 20
cy = 20
all_points = {}

function resetCurve()
  local ctrl = {cx, cy}
  for i=0, 2 do
    cx = love.math.random( MIN, MAX )
    cy = love.math.random( MIN, MAX )
    table.insert(ctrl, cx)
    table.insert(ctrl, cy)
  end
  curve = love.math.newBezierCurve(ctrl)
  points = 0
end

function love.load()
  resetCurve()
end

function love.update(dt)
  points = points + 1
  if points > DRAW_POINTS then
    resetCurve()
  end
  local x, y = curve:evaluate(points/DRAW_POINTS)
  table.insert(all_points, {x, y})
end

function love.draw()
    love.graphics.setBackgroundColor( 0.3, 0.3, 0.30)
    love.graphics.setColor(0.3, 0, 0, 0.1)
    love.graphics.line(curve:render())
    love.graphics.setColor(1, 0, 0)
    for i, point in pairs(all_points) do
      love.graphics.points(point)
    end
end