Note.
This is older code from when Lua was still new to me, you'd be better off looking at the Coracle package in the Calx game repo for a more up-to-date and better written version of this project. This repo will be improved with updated examples and code once Calx has shipped.
Coracle for Playdate
A port of Coracle to Lua to run on the Playdate.
Usage
Clone and open in Nova, change the drawing import in main.lua to switch drawings.
Drawings
These are ported from the Kotlin Coracle framework.
| Hello, Coracle | Shapes |
 |
 |
| Gravity | Avoid Closest |
 |
 |
| Perlin Flow Field | Self Organising |
 |
 |
Example
--[[
A port of Coracle Gravity: https://orllewin.github.io/coracle/drawings/vector/gravity/
]]
import 'Vector'
import 'SECL.lua'
local maxSpeed = 2.2
local bodyCount = 5
local blackhole = Vector:create(width/2, height/2)
local blackholeSize = 35
local blackholeMass = 0.4
local bodies = {}
function setup()
for i = 1 , bodyCount do
local boid = class:new()
boid.location = Vector:create(math.random(width), math.random(height))
boid.velocity = Vector:create(0, 0)
table.insert(bodies, boid)
end
end
function draw()
background()
fill(0.25)
circle(blackhole.x, blackhole.y, blackholeSize)
fill(1.0)
for i = 1, bodyCount do
circle(bodies[i].location.x, bodies[i].location.y, 5)
end
update()
end
function update()
for i = 1, bodyCount do
local body = bodies[i]
local blackholeDirection = vectorMinus(blackhole, body.location)
blackholeDirection:normalise()
blackholeDirection:times(blackholeMass)
body.velocity:plus(blackholeDirection)
body.location:plus(body.velocity)
for ii = 1, bodyCount do
if (i ~= ii) then
local other = bodies[ii]
bodyDirection = vectorMinus(body.location, other.location)
bodyDirection:normalise()
bodyDirection:times(0.03)
body.velocity:plus(bodyDirection)
body.velocity:limit(3.0)
body.location:plus(body.velocity)
end
end
end
if(crankUp())then
blackholeSize = blackholeSize + 0.5
blackholeMass = blackholeMass + 0.005
end
if(crankDown())then
blackholeSize = blackholeSize - 0.5
blackholeMass = blackholeMass - 0.005
end
end