[jitter] 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