Add boilerplate for level code

src/game.h

@@ -34,6 +34,11 @@ extern game_state_t game_state;
  */
 void title(void);
 
+/**
+ * @brief Render the current game level.
+ */
+void level(void);
+
 /**
  * @brief Enable interrupts.
  */

src/level.c

@@ -0,0 +1,12 @@
+#include "game.h"
+#include "sdk/hardware.h"
+#include "sdk/joypad.h"
+
+void level(void) {
+    while (1) {
+        joypad_update();
+
+        HALT();
+        rIF = 0;
+    }
+}

src/main.c

@@ -29,6 +29,10 @@ void main() {
             case GAME_STATE_TITLE:
                 title();
                 break;
+
+            case GAME_STATE_LEVEL:
+                level();
+                break;
         }
     }
 }

src/title.c

@@ -16,7 +16,6 @@ void title(void) {
 
     // Copy title screen to VRAM
     memcpy((uint8_t *)_VRAM, &bg_tiles[0], bg_tiles_end - bg_tiles);
-    // vram_memcpy(_VRAM, &bg_tiles[0], bg_tiles_end - bg_tiles);
 
     uint8_t *vram_ptr = (uint8_t *)_SCRN0;
     const uint8_t *map_ptr = &bg_map[0];