Bullet only removing closest enemy

Question

I'm having an issue with my collision detection code. I'm making a top down shooter and when I shoot, the bullet will only destroy an enemy if it's the closest enemy. The bullet will go right through the 2nd closest enemy.

Here is my code:

// Iterate through bullets, if bullet ccollides with enemy, remove both
for (int i = 0; i < Bullet.Bullets.Count; i++)
{
    if (Collisions.IsColliding(
      (int)Bullet.Bullets[i].position.X, (int)Bullet.Bullets[i].position.Y, 
      Bullet.sprite.Width, Bullet.sprite.Height,
      (int)Enemy.Enemies[i].position.X, (int)Enemy.Enemies[i].position.Y, 
      Enemy.sprite.Width, Enemy.sprite.Height))
    {
        Enemy.Remove(Enemy.Enemies[i]);
        Bullet.Remove(i);
    }
}

And here is my is colliding method:

public static bool IsColliding(int x1, int y1, int w1, int h1, int x2, int y2, int w2, int h2)
{
    return x1 < x2 + w2 &&
           x2 < x1 + w1 &&
           y1 < y2 + h2 &&
           y2 < y1 + h1;
}

Can anyone please point me in the right direction? Thank you.

Answer 1

You are only checking th i-th bullet with the enemy of the same index and not with every enemy there is.

You should do something like this

for (int i = 0; i < Bullet.Bullets.Count; i++)
{
    for (int j = 0; j < Enemy.Enemies.Count; j++)
    {
        if (Collisions.IsColliding(
          (int)Bullet.Bullets[i].position.X, (int)Bullet.Bullets[i].position.Y, 
          Bullet.sprite.Width, Bullet.sprite.Height,
          (int)Enemy.Enemies[j].position.X, (int)Enemy.Enemies[j].position.Y, 
          Enemy.sprite.Width, Enemy.sprite.Height))
        {
            Enemy.Remove(Enemy.Enemies[j]);
            Bullet.Remove(i);
        }
    }
}

This way you will check every bullet with every enemy, it's not the most efective way of doing it but it should work if you don't have tons of bullets and enemies at the same time.