Audio sync test for LÖVE

main.lua

--[[ Just an audio sync test I wrote for

https://bitbucket.org/rude/love/issues/1418/audio-source-tell-gets-out-of-sync-for

Issue has been long-since fixed but it might be useful to keep around for other testing purposes later?

]]

local stream, static

function love.load()
    stream = love.audio.newSource('01-little-bouncing-ball.mp3', 'stream')
    static = love.audio.newSource('01-little-bouncing-ball.mp3', 'static')
    stream:setVolume(0.5)
    static:setVolume(0.5)

    stream:play()
    static:play()
end

function getpos(player)
    -- 132BPM = 132/60 beats per second
    local time = player:tell()*132/60
    return math.floor(time/4), math.floor(time % 4), time % 1
end

function love.draw()
    local measure, beat, ofs = getpos(stream)
    local brt = math.pow(1 - ofs, 3)
    love.graphics.clear(0, 0, brt)

    love.graphics.setColor(1, 1, 1)
    love.graphics.print(string.format('%4d:%d:%f drift=%f', measure, beat, ofs, stream:tell() - static:tell()))

    love.graphics.setColor(0, 0, 1)
    drawBall(getpos(static))

    love.graphics.setColor(1, 1, 0)
    drawBall(measure, beat, ofs)
end

function drawBall(measure, beat, ofs)
    local w = love.graphics.getWidth()
    local h = love.graphics.getHeight()

    local x = ofs*w/2
    if beat % 2 == 1 then
        x = w*3/4 - x
    else
        x = w/4 + x
    end

    local y = (1 + 3*(ofs - 1)*ofs)*h - 16

    love.graphics.circle("fill", x, y, 16)
end