yvel/jumping example

function love.load()
    obj = {x=0, y=0, yvel=0}
    gravity = 800
end

function love.update(dt)
    obj.y = obj.y + obj.yvel
    obj.yvel = obj.yvel + gravity*dt
end

function love.draw()
    love.graphics.rectangle(obj.x,obj.y,50,50)
end