--Create a window
window = Window:Create()
context = Context:Create(window)
world = World:Create()
camera = Camera:Create()
camera:Move(0,0,-3)
local light = DirectionalLight:Create()
light:SetRotation(35,35,0)

--Create an emitter
emitter = Emitter:Create(100) 

local acceleration = -0.5
emitter:SetAcceleration(0,acceleration,0) 

while true do

    if window:Closed() or window:KeyHit(Key.Escape) then return false end

    Time:Update()
    world:Update()
    world:Render()

    if (window:KeyDown(Key.Up)) then
            acceleration = acceleration + .1 
            emitter:SetAcceleration(0,acceleration,0) 
    elseif (window:KeyDown(Key.Down)) then
            acceleration = acceleration - .1 
            emitter:SetAcceleration(0,acceleration,0) 
    end

    context:SetBlendMode(Blend.Alpha) 
    context:DrawText("Current Y-axis Acceleration: " ..emitter:GetAcceleration().y ,2,2) 

    context:Sync()
end