ogpng.lua

local gl = require("component").glasses
local png = require("libPNGimage")
local os = require("os") --used to avoid "too long without yielding"

local lib = {}

function lib.dot(x,y,r,g,b,a)
 r = r or 0
 g = g or 0
 b = b or 1
 a = a or 1
 local d = gl.addDot()
 d.setScale(1)
 d.setPosition(x,y)
 d.setColor(r,g,b)
 d.setAlpha(a)
 return d
end

function lib.fillHud(img, xx, yy, cache)
 local dots = {}
 local width, height = img:getSize()
 for x = 1, width do
  for y = 1, height do
   local dot = lib.dot(xx + x - 1, yy + y - 1, img:getPixel(x-1,y-1))
   if cache then table.insert(dots, dot.getID()) end
   os.sleep(0)
  end
 end
 return dots
end

function lib.pngToHud(f,x,y,cache)
 checkArg(1, f, "string")
 local fl,err = io.open(f, "rb")
 if not fl then error(err) end
 local img = png.newFromFileHandle(fl)
 return lib.fillHud(img,x or 0, y or 0, cache)
end

return lib