--By Nigelsheffield, script for averaging the altitdude readings intended for ds type lift.
--The idea is to get the highest and lowest points of each thermal/d.s circuit and then average the 2 together to give a stable readout of the altitude rather then lots of different readings taken at varying points in the circuit. the output will be spocken and switch on /off by a switch or logical switch  

local alt_id = getFieldInfo("altitude").id
local alt = 0
local lastalt = 0
local topalt = 0
local lowalt = 0
local topmark = 0
local lowmark = 0
local avalt = 0


local function run()

alt = getValue(alt_id) * 3.28 -- get height in feet, delete the * 3.28 if you want it in meters

if lastalt > alt and topmark == 0 then --we have reached the top of circuit detected by looking for a drop
	topmark = 1--mark as top reached no more drops will be noticed
	topalt = alt
		if topalt > (lowalt+0.5) then --filter small amount of turbulence change the 0.3 to suit	
				avalt = (topalt + lowalt) / 2
				playNumber(avalt, 0, 1)
		end
end


if lastalt < alt and topmark == 1 then --we have reached bottom by detecting climb
	topmark = 0
	lowalt = alt
end

lastalt = alt

	
end

return { run=run }