-- hello gba: a hardware sprite you move with the d-pad, plus a greeting.
--
-- This is how you actually make a GBA game. The screen is 240x160. cls paints
-- a hardware background layer that stays put; the sprite is a real hardware OBJ
-- (spr uses the built-in default sheet, so no asset file is needed). _update60
-- moves it on the d-pad every frame, _draw redraws it every frame - sprites are
-- cheap, you don't repaint the whole screen to move one.

local x, y = 112, 72

function _update60()               -- 60fps input + movement
  if (btn(1)) then x += 2 end      -- right
  if (btn(0)) then x -= 2 end      -- left
  if (btn(3)) then y += 2 end      -- down
  if (btn(2)) then y -= 2 end      -- up
end

function _draw()
  cls(1)                           -- dark-blue background layer
  print("hello gba", 88, 24, 14)   -- greeting near the top, pink
  spr(0, x, y, 2, 2)               -- the hardware sprite, redrawn every frame
end