Time for action – updating and drawing particles

1. Add an Update() method to the Particle class:

   Public Overrides Sub Update(gameTime As GameTime)
       If IsActive Then
           velocity += _acceleration
           If velocity.Length() > _maxSpeed
               velocity.Normalize()
               velocity *= _maxSpeed
           End If
           TintColor = Color.Lerp(
               _initialColor,
               _finalColor,
               DurationProgress)
           remainingDuration -= 1
           MyBase.Update(gameTime)
       End If
   End Sub

2. Add a Draw() method to the Particle class:

   Public Overrides Sub Draw(spriteBatch As SpriteBatch)
       If IsActive Then
           MyBase.Draw(spriteBatch)
       End If
   End Sub

What just happened?

Both the Update() and the Draw() methods, override the Sprite class' methods of the same name, because we need to alter the behavior associated with them. Both methods will only execute any code if the IsActive property returns true. In fact, for the Draw() method, this is the only reason we override...