PlaydateSequence

Create animations with simple sequences of easing functions in your playdate game

How to use sequence.lua on Playdate

Using toybox.py

You can add it to your Playdate project by installing toybox.py, going to your project folder in a Terminal window and typing:

toybox add Sequence
toybox update

Then, if your code is in the source folder, just import the following:

import '../toyboxes/toyboxes.lua'

Manually

You first need to copy the file sequence.lua in your playdate project and to import it

import 'sequence'

Creating animations

Chain easing functions

The main idea of sequence.lua is to easily have multiple easing functions play one after the other. To create an animation you simply chain multiple transitions:

local cool_animation = sequence.new():from(0):to(10, 0.3, "outCirc"):sleep(0.4):to(0, 0.5, "outExpo"):start()

Let's disconstruct this animation:

sequence.new() is creating a new sequence object
:from(0) is setting the initial value of the animation to 0
:to(10, 0.3, "outCirc") is telling the value to go to 10 in 0.3 seconds using the easing outCirc
:sleep(0.4) is telling to keep the value the same for 0.4 seconds
:to(0, 0.5, "outExpo") is telling the value to go to 0 in 0.5 seconds using the easing outExpo
:start() is starting to play the animation immediatly

You can also add :loop() so that the animation will loop indefinitely or :mirror() to loop the animation back and forth.

Update Loop

For the animation to be updated properly, you need also to call sequence.update() in your update function

function playdate.update()
	sequence.update()
  
  -- Your code ...
end

And to get the current value of the animation, you can simply call :get() on the sequence

local position_x = cool_animation:get()

Control the animation

You don't have to call :start() when you declare the animation. You can just start it when an event happens in your game. You can also call :pause() :stop() or :restart() to control when the animation is played in your code.

Callbacks

If you want to play a sound at specific points in the animation (or trigger other effects or gameplay feature) you can use :callback() in your sequence.

sequence.new():from(0):to(69, 4.2, "flat"):callback(function() print("Noice") end)

Best practice

When an animation is played in loop, it will be played forever even if you delete the animation unless you call :stop() or :pause(). The sequence system has a reference to the animation to know when to update it and as such, the animation cannot be deleted it by the garbage collector even when you dereference it.
To avoid creating object at run time, it is better to create your sequences at initialization (at boot or on level load) and to play them when needed.

gingerbeardman/PlaydateSequence