Time for action – the View matrix

1. 1. Add the following variable to the Fields region of the Camera class:

   private Matrix cachedViewMatrix;

2. 2. Add the following property to the Properties region of the Camera class:

   public Matrix View
   {
       get
       {
           if (needViewResync)
               cachedViewMatrix = Matrix.CreateLookAt(
                   Position, 
                   lookAt, 
                   Vector3.Up);
   
           return cachedViewMatrix;
       }
   }

What just happened?

We could simply recalculate the View matrix every time the Camera class was asked for it, but doing so would incur a small performance penalty. Because we do not have a lot of action happening in Cube Chaser, this penalty would not impact our game, but we can avoid it altogether. We are building a caching mechanism into the camera code in the event our game develops to the point that this optimization is helpful. Any time the View matrix is calculated, we will store it in cachedViewMatrix and simply return that matrix if the View...