Lutro

A 2D game engine for libretro

Supported platforms

Windows
Linux
Android
Apple
Nintendo
Sony
Web

What is Lutro?

Lutro is a 2D game framework that aims for simplicity and extreme portability.

Using lutro, you can develop any kind of 2D retro games, like NES or Genesis games, and run them on a wide range of platforms through RetroArch.

Lutro makes it easy to write games by using Lua and following the LÖVE API.

Portability is achieved through the libretro API: Lutro is just loaded as a plugin in a frontend like RetroArch which takes care of display, audio and inputs.

Quick Start

Lutro follows the LÖVE API. If you are already familiar with this framework, it should be easy to get started.

Drawing text

function love.load()
  font = love.graphics.newImageFont("font.png", "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
  love.graphics.setFont(font)
end

function love.draw()
  love.graphics.print("HELLO 123", 16, 32)
end

Drawing an image

function love.load()
  whale = love.graphics.newImage("whale.png")
end

function love.draw()
  love.graphics.draw(whale, 32, 32)
end

Playing a sound

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

You can also read the sample games if you prefer to learn by example.

Showcase

These are some examples of what kind of games you can create with Lutro:

Bobble
Spaceship
Vespa
Deep Dungeon
Tetris
Sienna 3
Platformer
Bomberman
Tactical
Onion Kidd

Frequently Asked Questions

Why not using LÖVE directly?

Lutro supports less feature than LÖVE, but is more portable (see the list of supported platforms). Being able to run lutro games in a libretro frontend open some new possibilities like Run-ahead, Rewind and Rollback netcode.

Why not simply porting LÖVE to libretro?

We wanted a software rendered version to target some platforms without a GPU.
Also we want to expose some new API inpsired by emulators like savestates.
The fact that LÖVE main loop is implemented in Lua is incompatible with retro_run from libretro, it prevents executing the game step by step.

Does lutro follow the API of LÖVE exactly?

No, some calls are not implemented at all. Only the strict minimum to be able to produce retro games have been implemented.
Some parts of the input code has also been modified to follow the libretro API more closely.

Is lutro free?

Yes, lutro is distributed under the MIT license, you can use it freely, including for commercial projects.

How to run lutro games?

You launch them using RetroArch or Ludo or any other libretro frontend. Lutro works like an emulator, and your game is the ROM.
See Getting started.

Can I port LÖVE games to lutro?

Yes, but it's not very easy. A few games have been ported from LÖVE, like Sienna or In Your Face City Trains.