XNA 4.0 Game Development by Example Beginner's Guide

Time for action – power-ups

1. Add the following declarations to the WeaponManager class:

   static public List<Sprite> PowerUps = new List<Sprite>();
   static private int maxActivePowerups = 5;
   static private float timeSinceLastPowerup = 0.0f;
   static private float timeBetweenPowerups = 2.0f;
   static private Random rand = new Random();

2. Add the tryToSpawnPowerup() method to the Weapons Management Methods region of the WeaponManager class:

   private static void tryToSpawnPowerup(int x, int y, WeaponType type) { if (PowerUps.Count >= maxActivePowerups) { return; } Rectangle thisDestination = TileMap.SquareWorldRectangle(new Vector2(x,y)); foreach (Sprite powerup in PowerUps) { if (powerup.WorldRectangle == thisDestination) { return; } } if (!TileMap.IsWallTile(x,y)) ...