/* KEY INPUT WORKS, BUT MOUSE DOESN'T
public class FreeCamera
    {
        private Vector3 position_;
        private Vector3 rotation_;
        private Vector3 lookAt_;
        private Vector3 direction_;
        private float speed_ = 0.1f; 
        private Vector3 mouseRotationBuffer_;
        private MouseState pastMouse_;
        

        public FreeCamera()
        {
            pastMouse_ = Mouse.GetState();
            resetCamera();
        }

        public Vector3 Position 
        { 
            get 
            { return position_; }

            set 
            { 
                position_ = value;
                updateLookAt();
            }
        }

        public Vector3 Rotation 
        { 
            get { return rotation_; }
            set 
            { 
                rotation_ = value;
                updateLookAt();
            }
        }

        public Vector3 Direction { get { return direction_; } }
        

        public void resetCamera()
        {
            position_ = new Vector3(0, 0, 50);
            speed_ = 0.3f;
            rotation_ = Vector3.Zero;
            
        }

        private void updateLookAt()
        {
             Matrix rotationMatrix = Matrix.CreateRotationX(rotation_.X) * 
                                     Matrix.CreateRotationY(rotation_.Y);
            
            direction_ = Vector3.Transform(Vector3.UnitZ, rotationMatrix);
            lookAt_ = position_ + direction_;
        }

        private void cameraInput(float panelWidth, float panelHeight, float deltaTime)
        {
            
            KeyboardState keyboardState = Keyboard.GetState();
            MouseState currentMouse = Mouse.GetState();

            Vector3 moveVector = Vector3.Zero;
            float deltaX, deltaY;

            if (currentMouse != pastMouse_)
            {
                deltaX = Mouse.GetState().X - (panelWidth / 2);
                deltaY = Mouse.GetState().Y - (panelHeight / 2);

                mouseRotationBuffer_.X -= 0.01f * deltaX * deltaTime;
                mouseRotationBuffer_.Y -= 0.01f * deltaY * deltaTime;

                if (mouseRotationBuffer_.Y < MathHelper.ToRadians(-75.0f))
                    mouseRotationBuffer_.Y -= (mouseRotationBuffer_.Y - MathHelper.ToRadians(90.0f));
                if (mouseRotationBuffer_.Y < MathHelper.ToRadians(90.0f))
                    mouseRotationBuffer_.Y -= (mouseRotationBuffer_.Y - MathHelper.ToRadians(90.0f));

                Rotation = new Vector3(-MathHelper.Clamp(mouseRotationBuffer_.Y, MathHelper.ToRadians(-75.0f),
                    MathHelper.ToRadians(90.0f)), MathHelper.WrapAngle(mouseRotationBuffer_.X), 0);

                deltaX = 0;
                deltaY = 0;
            }

            if (keyboardState.IsKeyDown(Keys.W))
                moveVector.Z += 1;
            if (keyboardState.IsKeyDown(Keys.S))
                moveVector.Z -= 1;
            if (keyboardState.IsKeyDown(Keys.A))
                moveVector.X += 1;
            if (keyboardState.IsKeyDown(Keys.D))
               moveVector.X -= 1;
            if (keyboardState.IsKeyDown(Keys.R))
                moveVector.Y += 1;
            if (keyboardState.IsKeyDown(Keys.F))
                moveVector.Y -= 1;

            if (moveVector != Vector3.Zero)
            {
                moveVector.Normalize();
                moveVector *= speed_;

                Move(moveVector);

                pastMouse_ = currentMouse;
            }
        }

        public void update(float panelWidth, float panelHeight, float timer)
        {
            cameraInput(panelWidth, panelHeight, timer);
        }


        public void MoveTo(Vector3 position, Vector3 rotation)
        {
            Position = position;
            Rotation = rotation;
        }


        public Vector3 PreviewMove(Vector3 amount)
        {
            Matrix rotate = Matrix.CreateRotationY(Rotation.Y);
            Vector3 movement = new Vector3(amount.X, amount.Y, amount.Z);
            movement = Vector3.Transform(movement, rotate);
            return Position + movement;
        }

        public void Move(Vector3 scale)
        {
            MoveTo(PreviewMove(scale), Rotation);
        }
    }