--add these two lines to load the opengl library
local gl = require("opengl")
local GL = gl

--initialize variables
MAIN={}
xpos=-1
xinc=.01
xmax=200
ON=1

--fill MAIN with zeroes
for i=1,xmax do
MAIN[i]=0
end

--on/off switch
function enable(e)
ON=e
end

--change distance between lines
function inc(x)
xinc=x
end

--change total number of lines
function lines(x)
xmax=x
end

--Make MAIN a First-In, First-Out (FIFO) table
function float(f)
if ON == 1 then
table.remove(MAIN,1)
table.insert(MAIN,f)
--outlet(0,MAIN)
end
end

--function draw() is a special function called 
--each frame
function draw()
if ON == 1 then
	gl.Enable(GL.BLEND)
	gl.BlendFunc(GL.SRC_ALPHA, GL.ONE)
	gl.Disable(GL.DEPTH_TEST)
	
for i=1,xmax do
--make xpos wrap around
	if (xpos > xinc*(xmax/2)) then xpos = -xinc*(xmax/2) end
--increment xpos
	xpos=xpos+xinc
--draw lines
	gl.Begin(GL.LINES)
		gl.Color(1,1,1)
		gl.Vertex(xpos,MAIN[i],0)
		gl.Vertex(xpos,-MAIN[i],0)
	gl.End()	
	end
 end
end