Making player movement direction follow players facing direction

Question

if (controller.isGrounded) {
                        moveDirection = new Vector3 (Input.GetAxis ("Horizontal"), 0, Input.GetAxis ("Vertical"));
                        moveDirection = transform.TransformDirection (moveDirection);
                        moveDirection *= speed;
                        if (Input.GetButton ("Jump"))
                                moveDirection.y = jumpSpeed;

                }
                moveDirection.y -= gravity * Time.deltaTime;
                controller.Move (moveDirection * Time.deltaTime);

This works. I can manover my player in any direction.

With the awsd keys i can create 8 directions. I would like player to rotate towards the direction of the keys pressed. This is a top down game. So W+D would take you diagonally right/up. S+D would take you diagonally right/down.

I want the player to rotate into that direction, but also move the direction it is facing. Like a car. So if it is facing a complete different direction then it would actually move not in the target direction for a while until it has the target direction. Am i making sense?

      if (moveDirection != Vector3.zero) 
    {
transform.rotation = Quaternion.LookRotation (moveDirection);
                        }

Answer 1

Don't move the player's position directly in response to keyboard input. Instead always move the player forward relative to the direction it's facing, and lerp to different rotations based on keyboard input.