bootstrap lua

flake.nix

@@ -12,11 +12,14 @@
   outputs = { self, nixpkgs, playdate-sdk }:
     let system = "x86_64-linux";
         pkgs = nixpkgs.legacyPackages.${system};
+        stdenv = pkgs.stdenv;
         playdate-sdk-pkg = playdate-sdk.packages.${system}.default;
     in {
-      devShell.${system} = with pkgs;
+      devShell.${system} = with stdenv; with pkgs;
         mkShell {
           nativeBuildInputs = [
+            just
+            lua-language-server
             playdate-sdk-pkg
           ];
         };

justfile

@@ -0,0 +1,9 @@
+bin := "Rush.pdx"
+
+alias b := build
+build:
+    pdc src {{ bin }}
+
+alias s := simu
+simu: build
+    PlaydateSimulator {{ bin }}

src/main.lua

@@ -0,0 +1,95 @@
+-- Name this file `main.lua`. Your game can use multiple source files if you wish
+-- (use the `import "myFilename"` command), but the simplest games can be written
+-- with just `main.lua`.
+
+-- You'll want to import these in just about every project you'll work on.
+
+import "CoreLibs/object"
+import "CoreLibs/graphics"
+import "CoreLibs/sprites"
+import "CoreLibs/timer"
+
+-- Declaring this "gfx" shorthand will make your life easier. Instead of having
+-- to preface all graphics calls with "playdate.graphics", just use "gfx."
+-- Performance will be slightly enhanced, too.
+-- NOTE: Because it's local, you'll have to do it in every .lua source file.
+
+local gfx <const> = playdate.graphics
+
+-- Here's our player sprite declaration. We'll scope it to this file because
+-- several functions need to access it.
+
+local playerSprite = nil
+
+-- A function to set up our game environment.
+
+function myGameSetUp()
+
+    -- Set up the player sprite.
+
+    local playerImage = gfx.image.new("Images/playerImage")
+    assert( playerImage ) -- make sure the image was where we thought
+
+    playerSprite = gfx.sprite.new( playerImage )
+    playerSprite:moveTo( 200, 120 ) -- this is where the center of the sprite is placed; (200,120) is the center of the Playdate screen
+    playerSprite:add() -- This is critical!
+
+    -- We want an environment displayed behind our sprite.
+    -- There are generally two ways to do this:
+    -- 1) Use setBackgroundDrawingCallback() to draw a background image. (This is what we're doing below.)
+    -- 2) Use a tilemap, assign it to a sprite with sprite:setTilemap(tilemap),
+    --       and call :setZIndex() with some low number so the background stays behind
+    --       your other sprites.
+
+    local backgroundImage = gfx.image.new( "Images/background" )
+    assert( backgroundImage )
+
+    gfx.sprite.setBackgroundDrawingCallback(
+        function( x, y, width, height )
+            -- x,y,width,height is the updated area in sprite-local coordinates
+            -- The clip rect is already set to this area, so we don't need to set it ourselves
+            backgroundImage:draw( 0, 0 )
+        end
+    )
+
+end
+
+-- Now we'll call the function above to configure our game.
+-- After this runs (it just runs once), nearly everything will be
+-- controlled by the OS calling `playdate.update()` 30 times a second.
+
+myGameSetUp()
+
+-- `playdate.update()` is the heart of every Playdate game.
+-- This function is called right before every frame is drawn onscreen.
+-- Use this function to poll input, run game logic, and move sprites.
+
+function playdate.update()
+
+    -- Poll the d-pad and move our player accordingly.
+    -- (There are multiple ways to read the d-pad; this is the simplest.)
+    -- Note that it is possible for more than one of these directions
+    -- to be pressed at once, if the user is pressing diagonally.
+
+    if playdate.buttonIsPressed( playdate.kButtonUp ) then
+        playerSprite:moveBy( 0, -2 )
+    end
+    if playdate.buttonIsPressed( playdate.kButtonRight ) then
+        playerSprite:moveBy( 2, 0 )
+    end
+    if playdate.buttonIsPressed( playdate.kButtonDown ) then
+        playerSprite:moveBy( 0, 2 )
+    end
+    if playdate.buttonIsPressed( playdate.kButtonLeft ) then
+        playerSprite:moveBy( -2, 0 )
+    end
+
+    -- Call the functions below in playdate.update() to draw sprites and keep
+    -- timers updated. (We aren't using timers in this example, but in most
+    -- average-complexity games, you will.)
+
+    gfx.sprite.update()
+    playdate.timer.updateTimers()
+
+end
+