function love.load()
	--options
	love.graphics.setColor(1,1,1)
	love.graphics.setDefaultFilter("nearest") -- good pixel

  SCREEN_WIDTH = love.graphics.getWidth()
  SCREEN_HEIGHT = love.graphics.getHeight()

  -- simulation variables
  CONST_G = 39.5
  TIME_SPEED = 0.05
  CONST_S = 0.15

  T = 0

  require "class"
	require "body"

	newBody(0,0,300,{1,0,0})
	newBody(0,0.1,100,{0,1,0})
	newBody(0.1,0,200,{0,0,1})
	newBody(0.1,0.1,50,{1,1,0})
	newBody(0.1,0.2,250,{1,0,1})
	newBody(0.2,0.1,150,{0,1,1})

end

function love.update(dt)

  T = T + dt
  while T > TIME_SPEED do
    UpdateBodiesAcceleration()
    UpdateBodiesVelocity(dt)
    UpdateBodiesPosition(dt)
    T = T - TIME_SPEED
  end
end

function love.draw()
  -- draw bodies
  for n, body in pairs(BodyList) do
    love.graphics.setColor(body.color[1],body.color[2],body.color[3])
    love.graphics.circle("line",body.x+SCREEN_WIDTH/2,body.y+SCREEN_HEIGHT/2,10)
  end
  -- draw info
  love.graphics.setColor(1,1,1)
  love.graphics.print(T.."/"..TIME_SPEED)
  for n, body in pairs(BodyList) do
    love.graphics.print("mass: "..body.mass.." x,y: "..body.x..", "..body.y,0,15*(n))
  end
end