GameScene.hx

class GameScene extends Scene {
  // ...

  public override function update() {
    // Keep camera.x centered on the player
    HXP.camera.x = player.x - HXP.halfWidth + 64;

    // Keep camera.y centered on the player,
    // unless it would show below the map.
    // In that case, keep to the bottom fo the map.
    if (HXP.camera.y + HXP.height >= map.map.fullHeight) {
      HXP.camera.y = HXP.halfHeight + 64;
    } else {
      HXP.camera.y = player.y - HXP.halfHeight + 64;
    }

    super.update();
  }
}