As someone who only started with Lua and Playdate recently, I hope I can help explain what's wrong here and how to fix it!
You want to make a sprite that's a triangle. A sprite is its own kind of object; assigning it to the result of a draw function won't quite work. Sprites have their own draw functions. You wan't something like this:
import "CoreLibs/object"
import "CoreLibs/graphics"
import "CoreLibs/sprites"
import "CoreLibs/timer"
local gfx <const> = playdate.graphics
local playerShip = nil
function myGameSetUp()
playerShip = gfx.sprite.new() -- this is how create a new sprite, almost always
-- by the way, playerShip has already been created above, as a file-local var
-- we probably don't want to make this sprite local to just this function,
-- or we couldn't control it from anywhere else in the code
playerShip:setSize(50, 50) -- unless we make the sprite a bitmap image, we need to set its size
-- this is the function that will run whenever this sprite is drawn
function playerShip:draw()
gfx.drawTriangle(0,0, 50,20, 20, 50)
end
-- …another way to give a sprite an image is to either load a bitmap file,
-- OR, draw INTO a bitmap file and set that as the sprite's image
-- with sprite:setImage. But let's stick with this for now!
playerShip:moveTo(200, 120)
playerShip:add()
end
myGameSetUp()
function playdate.update()
playdate.timer.updateTimers() -- we're not actually using timers for anything yet…
gfx.sprite.update() -- …but we do have to update all sprites in the update loop!
end
