Selene OLed graphical plug-in

PowerGraph.sel

#!./Selene
-- Exhibits how to do some simple graphs

------
-- Configurations
------

-- Where to get data from in this example, it's the current consumed but my
-- BananaPI from it's PMU
local ISOURCE = "/sys/devices/platform/sunxi-i2c.0/i2c-0/0-0034/axp20-supplyer.28/power_supply/ac/current_now"
local VSOURCE = "/sys/devices/platform/sunxi-i2c.0/i2c-0/0-0034/axp20-supplyer.28/power_supply/ac/voltage_now"
local SAMPLE = 1 -- Delay b/w samples

-- Helper
if not table.pack then
    function table.pack (...)
        return {n=select('#',...); ...}
    end
end

Selene.UseOLED()

if not arg or #arg ~=2 then
	print "Missing expected arguments :"
	print "- Screen identifier"
	print "- I2c bus to use"
	print ""
	print("Example : ", SELENE_SCRIPT_NAME .." 2 /dev/i2c-2")
	print ""

	print "Known screens :"
	print("ident","name")
	local l = table.pack( SelOLED.oled_type() )
	for _,x in ipairs(l)
	do
		print(_, x)
	end
else
	if SelOLED.Init(arg[1], arg[2]) == false then
		error("Can't open I2C Device\n")
	end

	SelOLED.Flip(true)	-- If needed

		-- The graph position and size
	local offx,offy = 10,37
	local w,h = SelOLED.Width()-offx-2, SelOLED.Height()-offy-2

	local col = SelCollection.create(w-1)	-- Create a collection

	while true do
		local f = io.open(ISOURCE,'r')
		local vi = f:read('*n') / 1e6
		f:close()
		f = io.open(VSOURCE,'r')
		local vu = f:read('*n') / 1e6
		f:close()
		local pwr = vu * vi
		col:Push(pwr)

		SelOLED.Clear()
		SelOLED.SetTextColor(1)
		SelOLED.SetTextSize(2)
		SelOLED.SetCursor(0,0)
		SelOLED.Print(Selene.Hostname())

		SelOLED.SetTextSize(1)
		SelOLED.SetCursor(0,19)
		local max,min = math.ceil(pwr)
		SelOLED.Print(string.format("p:%.1f u:%.01f i:%.02f  %d",pwr, vu, vi, max))
		SelOLED.HorizontalGauge(0,29, SelOLED.Width(),6, pwr/max*100)

		min,max = col:MinMax()
		if max ~= min then
			min,max = math.floor(min), math.ceil(max)

			SelOLED.SetCursor(0,37)
			SelOLED.Print(max)
			SelOLED.SetCursor(0,SelOLED.Height()-8)
			SelOLED.Print(min)

			SelOLED.Line(offx-1,offy, offx-1,offy+h+1)
			SelOLED.Line(offx-1,offy+h+1, offx+w+1,offy+h+1)

			local sy = h/(max-min) -- vertical scale
			local sx = w/(col:HowMany()-1) -- -1 as the 1st one doesn't have offset

			local x,y = 0	-- Previous value and position
			for v,t in col:iData() do
				if y then
					x = x+1
					SelOLED.Line(
						offx + (x-1)*sx, offy+h - (y-min)*sy,
						offx + x*sx, offy+h - (v-min)*sy
					)
				end
				y = v
			end
		end

--[[
		if col:GetSize() == col:HowMany() and not grabbed then
			SelOLED.SaveToPBM("/tmp/tst.pbm")
			print "grabbed"
			grabbed = true
		end
]]

		SelOLED.Display()
		Selene.Sleep(SAMPLE)
	end
end
Selene OLed plug-in

Examples

Classes

PowerGraph.sel
