Forgetful Notes

LÖVE

LÖVE is a framework you can use to make 2D games in Lua. It’s free, open-source, and works on Windows, macOS, Linux, Android and iOS.

Examples

Hello World

This is the full source for ‘hello world’ in LÖVE. Running this code will cause an 800 by 600 window to appear, and display white text on a black background:

function love.draw()
    love.graphics.print('Hello World!', 400, 300)
end

Draw an Image

function love.load()
    whale = love.graphics.newImage("whale.png")
end
function love.draw()
    love.graphics.draw(whale, 300, 200)
end

Play a Sound

function love.load()
    sound = love.audio.newSource("music.ogg", "stream")
    love.audio.play(sound)
end

Functions

love.load()

This function is called at the beginning and it’s supposed to load all your data and variables.

function love.load()
    hero = {}
    hero.name = "Ruben"
    hero.health = 100
    hero.alive = true
    score = 0
end

love.update

This function runs repeatedly during the session. The variable dt is used to update your data, as it marks the time passed since it last ran.

function love.update(dt)
    if hero.health < 1 then
        hero.alive = false
    end
    if enemy.dead then
        score = score + 1
    end
end

love.draw

Like love.update, this function is also called continuously, but rather than calculate the values, it draws game elements on the screen.

function love.draw()
    love.graphics.print(score, 400, 300)   
end

The value being printed score would constantly be redrawn, but since we are also updating the value of it in the update function, on every redraw we would get the most updated value.

Beyond the Basics

Movement

if love.keyboard.isDown("right") then
    hero.x = hero.x + hero.speed * dt
end

Drawing Elements

love.graphics.rectangle("line", 400, 300, 100, 100)

Drawing an Image

love.graphics.draw("path to img", 400, 300, 100, 100)

License

LÖVE is licensed under the liberal zlib/libpng license. This means that:

  • It costs nothing.
  • You can use it freely for commercial purposes with no limitations.

The source can be found on GitHub.

Graph View