Time for action – expanding the Camera

1. 1. In the Helper Methods region of the Camera class, add the following new methods:

   public Vector3 PreviewMove(float scale)
   {
       Matrix rotate = Matrix.CreateRotationY(rotation);
       Vector3 forward = new Vector3(0, 0, scale);
       forward = Vector3.Transform(forward, rotate);
       return (position + forward);
   }
   
   public void MoveForward(float scale)
   {
       MoveTo(PreviewMove(scale), rotation);
   }

What just happened?

PreviewMove() accepts a distance we wish to move along the direction that the camera is facing. It then calculates a matrix which is used to rotate a vector by the current camera rotation. Recall that an unrotated camera will always be pointing in the 0, 0, 1 direction, so we replace the 1 in this vector with the distance we wish to move, creating vector forward. We then apply the rotate transform to this vector, resulting in a vector that points in the direction the camera is actually facing, with a length equal to the distance we want to...