settimeout in lua?

Hi,
In Lua, coroutines extend very nicely into time-based parameter
modeling. A coroutine is kind of like a lightweight thread that runs
a function in another process but doesn't actually spawn another
thread, that is just the model. It can be a bit confusing at first
but is a very useful concept for all kinds of collaborative processes.
In the example below, I haven't made nice wrapper functions for the
coroutine code, so it's all flat. One could design a cleaner
interface by grouping together certain operations in higher-level
functions.

wes

function fade_in(start, done, incr)
    while(start < done) do
        coroutine.yield(start)    --pass value to resume
        start = start + incr
    end
end

local coros = {}
local num_lines = 100
for i=1, num_lines do
    --create a new function with fade params as upvalues
    coros[i] = coroutine.create(function() fade_in(math.random()*-5,
math.random()*5, math.random()*0.2+0.1) end)
end

function draw()
    gl.Enable("BLEND")
    gl.BlendFunc("SRC_ALPHA", "ONE")

    for i, c in pairs(coros) do
        local status, val = coroutine.resume(c)    --get the current value
        if(val) then

            gl.Color(1, 0, 0, 0.4)
            gl.Begin("LINES")
                gl.Vertex(val, 1, 0)
                gl.Vertex(val, -1, 0)
            gl.End()

        else
            table.remove(coros, i)
        end
    end
end